Innovative Bridge Designs for Rapid Renewal (2014)

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244 Focus Group and Survey Results First Owners Survey Results The owners survey was created to gain insight into the suc- cessful practices of bridge owners engaged in accelerated bridge construction and to learn about the challenges faced by bridge owners who have not been successful with ABC. The survey contains 40 questions that focus on ABC goals, prac- tices, experiences, hindrances, and opinions. The advanced tools of the survey allowed questions to be displayed or hidden depending on the respondent’s answers, so only the questions deemed applicable were answered. • 38 completed surveys were submitted by officials from many agencies throughout the United States, • 68 surveys were abandoned, and • 24 were partially completed. The questions in the owners survey were created to provide information on several aspects of an agency’s experience and views of ABC. The survey consists of four pages, with the questions on each page geared toward soliciting information about a specific aspect of ABC. The first page serves as an introduction and presents questions designed to gauge the agency’s overall view of ABC. If that agency has experience with ABC techniques, a series of questions are presented to determine both the type of ABC elements with which the agency has experience and whether or not the agency would consider using those elements again. The second page con- tains questions about the agency’s goals for ABC, what aspects are most appealing, and whether the agency is engaged in research or looking for opportunities to use ABC. The survey also asks agencies to evaluate their readiness to implement various ABC techniques to determine what might be keeping agencies from using ABC. The third page asks respondents to describe a specific project that they may have completed using ABC techniques. Those responses were used for follow- up purposes: Rather than using them to learn more about an agency’s views on ABC, they were used to find previously unknown projects that could provide useful information on innovative techniques and practices. The fourth page pro- vides space for respondents to describe any ABC practices they feel might be important to this study as well as any additional feedback regarding the survey. Respondents were required to provide contact information for follow-up, although the team did ask for their permission to contact them for additional information. Owner ABC Implementation The first series of questions pertain to the current level of experience, attitudes, and familiarity with ABC as a project delivery method. Though U.S. deployment of ABC is not nearly as common as it is in Europe, many state DOTs have some experience with certain aspects of ABC, such as prefab- ricated elements, complete bridge movement, or innovative contracting methods. Thus, 73% of the agencies responded that they had experience with some aspect of ABC delivery. When asked about their agency’s disposition toward ABC, the following results were obtained: • 82% of respondents indicated an impetus to implement ABC, suggesting that many agencies are looking for ways to enhance the speed with which bridge projects are delivered. Respondents reported that DOT executives, department heads, staff, consultants, and fabricators and suppliers are very supportive or supportive of ABC implementation. • 95.4% of DOT executives, 88.7% of department heads, and 73.3% of staff are very supportive or supportive of ABC implementation. Those results suggest that support for ABC is highest at the executive levels but is generally present at all critical levels of the organization. That implies that DOT staff, contractors, consultants, fabricators, and suppliers would benefit most A p p e n d i x B

245 from ABC information sessions, as the lack of information on ABC has been identified as a hindrance for many agencies. When states lacking experience in ABC methods were queried, the top reason cited for unsuccessful implementation of ABC was a lack of funding. One respondent cited a lack of appro- priate opportunities for ABC implementation. Given that ABC methods are new to many agencies, respondents were asked if they are currently involved in any aspect of research related to ABC deployment; 43% responded affirmatively. Owner Project Experiences The owners were asked a series of questions about various types of ABC solutions they have tried. In particular, the questions focused on prefabricated solutions, accelerated construction techniques, contracting methods, project selec- tion, and selection criteria. Depending on their responses to those questions, owners were also asked whether the ABC applications were successful and whether they would use such solutions again. This portion of the survey included numerous data-laden questions to help the team gain a gen- eral understanding of the experiences of various owners. Abbreviated responses follow here. When asked to select the types of ABC elements with which their agency had experience, respondents gave varied answers since a large number of choices were provided. This indicates that owners do not necessarily agree that only certain types of solutions are suitable for accelerated construction. In general, the strongest conclusion relates to project satisfaction and potential reuse. Owners expressed a high degree of satisfac- tion with completed ABC projects and a strong likelihood to use the techniques again. In questions about why they used ABC techniques, respon- dents were asked to rate the importance of various criteria: traffic disruption mitigation, environmental impact mitiga- tion, public safety, worker safety, enhanced durability, lower life-cycle costs, and public satisfaction. Most of these were cited as very important or important considerations in choos- ing to implement ABC. Respondents were not asked to rank the various criteria. • Environmental impact mitigation was least likely to be cited as very important or important but still earned a high response rate of 64%. • The criterion most likely to be considered very important or important was traffic disruption mitigation at 98%. Agencies were queried about their project selection process. Roughly three-quarters of the respondents said that they do not have an identification system to select projects that are well suited for ABC implementation. Among the roughly one- quarter of respondents who do have such a system, it is used mostly in the preliminary engineering phases. For the states without a selection process, most respondents (71%) seem to think such an evaluation method would be helpful in making informed decisions about ABC implementation. With regard to factors that influence project selection, of the many factors that agencies were able to choose from, only noise pollution, cost, and shorter construction time did not positively affect an agency’s decision to choose a project for ABC. At the top of the list for positively influencing the selection of ABC techniques was traffic congestion. That implies an ABC technique is more likely to be implemented if it reduces traffic congestion than if it shortens construction time, even though lessened traffic con- gestion can be a direct result of shortened construction time. The survey asked a series of questions to determine the readi- ness of the respondent’s agency to implement several ABC techniques. The respondents were asked if their agency could immediately implement a specific method (e.g., extensive use of prefabrication, use of SPMTs, and so on.) or if further development was needed. The respondents were allowed to choose from three reasons as to why further development was necessary to implement a certain method: it requires additional research, legislative action, or institutional change. Methods that the respondent’s agency considers experimental or meth- ods with which the agency is unfamiliar were categorized as requiring further research. Some methods, such as certain con- tract types, might only be available following legislative action, such as a disaster declaration. Other methods might face insti- tutional roadblocks, such as unwillingness within the agency to pursue ABC. A majority of respondents considered their agency ready to implement all of the methods except the extensive prefabrica- tion of substructure. • 42% of respondents indicated that extensive prefabri- cation of substructure elements could be implemented immediately. • 79% of respondents indicated more research was needed. • 37% said that institutional change was required. Notably, all the states with significant seismic design require- ments felt that extensive substructure prefabrication was not immediately viable and that additional research was needed. First Owners Survey Observations While most agencies are aware of ABC, very few practice it on a large scale. According to the survey results, agencies are ready to implement many ABC techniques in theory, yet ABC has yet to gain significant traction. Some techniques are viewed as too new and requiring research and development; in other cases, ABC simply lacks a champion to push for its implementation on bridge projects.

246 ABC has distinct benefits that are definitely attractive to many agencies. However, despite the gradual lowering of costs and life-cycle cost savings, DOTs are hesitant to use ABC tech- niques because of their higher initial costs. ABC has been used on emergency replacement projects as well as on typical high- way overpass replacement projects. And when an agency has used certain techniques, it has generally been pleased with the results. Nonetheless, few agencies have committed to using those same techniques as part of an overall ABC program. Owner Personal Interviews As a supplement to the electronic online survey, multiple owners were contacted individually by team members to gain their insights into various aspects of ABC. (The survey con- tained questions for owners both with and without experi- ence.) Detailed responses were collected from Arkansas, Massachusetts, Mississippi, Missouri, New Jersey, New Hamp- shire, New York, North Carolina, Texas, Utah, Washington, and Wisconsin as well as the Federal Highway Administration. Of those, only Arkansas and Massachusetts indicated they did not have experience with ABC projects; the experiences of the other states were highly varied. Little consistency of effort or experience is evident among the states at this point. A brief description of the findings from the interviews and conver- sations is presented on a state-by-state basis. Arkansas Arkansas is an example of a state with no active ABC program. The Arkansas DOT’s perspective on project acceleration is that it should be done when it is possible to reduce project costs. Construction time savings are considered secondary and have a limited ability to provide project incentives. The perception is that ABC projects will be more expensive and thus counter to the desire for cost savings. There is some inter- est in ABC use but no active programs. California Caltrans described several recent projects in which various ABC methods were employed. For the I-40 Marble Wash bridge replacements, a series of bridges were replaced by using prefabricated or precast concrete abutments and bulb tee construction. Complete reconstruction was accomplished in 4 weeks and was required because of high average daily traffic (ADT). Caltrans indicated that meaningful incentives and disincentives greatly motivated the contractor. For the Oakland Bay Bridge approach span replacements at Yerba Buena Island, large spans were replaced by using a skidding system with a complete closure of 3 days over a holiday week- end. The agency estimated that the costs greatly exceeded a conventional project; yet a conventional project would not have been possible or would have involved very difficult traf- fic staging. Again, significant incentives and disincentives were used. In general, individuals at multiple levels within Caltrans expressed a strong degree of interest in and support for ABC projects, as did local fabricators and trade associations. They generally agreed that the role of the designer should be to develop plans for ABC projects in conjunction with con- struction staff to maximize the constructability of the proj- ect. Several limitations inhibit the greater use of accelerated construction techniques for Caltrans, including seismic con- cerns limiting use of precast pier elements, long-term dura- bility, and concerns about the ability to balance the increase in construction costs against the user costs savings. Mississippi The Mississippi DOT has significant experience in recent Gulf Coast reconstruction (following Hurricane Katrina) with precast concrete cap beams. The agency is reluctant to use precast columns or footings because of concerns about connection durability and would welcome the development of durable connections for those precast elements. It does not use integral abutments because of concerns about approach slab connection details. The Mississippi DOT has heard com- plaints from contractors about the diminished profitability of projects using large precast elements. That concern is perceived as more of a political issue than a construction concern. The agency expressed the opinion that many bridge construction projects are not on a critical path—roadway ele- ments drive the schedule. In those cases they see a diminished value in acceleration. In practice, ABC is applied selectively at this point and is reserved for emergency reconstruction or projects with spe- cial conditions such as emergency access or site constraints. The Mississippi DOT senior management must be convinced of the advantages of acceleration. In the meantime, managers would appreciate having a catalog of ideas to choose from as opposed to prescriptive standards when deciding how or whether to pursue an ABC project. As a small state, they feel that a regional consensus is needed for ABC to move forward since contractors and fab- ricators in their part of the country work in multiple states. They believe that the local fabricators would embrace new shapes and technologies as long as a commitment to a large number of projects was made. Individuals expressed an inter- est in seeing actual comparisons of conventional versus ABC schedules and cost estimates to justify the advantages to senior management. They are also interested in data on durability of joints and connections between precast elements as this is a hindrance right now in their use of such systems.

247 Missouri Individuals at the Missouri DOT cited various examples of recent ABC deployment, including their frequent use of stay- in-place concrete deck panels, the successful use of Inverset systems, and a long bridge redecked with full-depth precast deck panels with nighttime closures. They also cited the use of adjacent box beams with a concrete topping erected as an emergency replacement and the application of latex-modified high-early-strength wearing surfaces in lieu of conventional overlays as a way of expediting highway reopening times. Those projects were substantially more expensive than the agency’s conventional approaches but done with ABC tech- niques because of traffic constraints. The Missouri DOT does not have a formal process for ABC implementation but takes the position that it must minimize traffic impacts to the extent possible with available project funds. In their experience, ABC significantly increases project expenses and must be used judiciously. The agency encour- ages the submission of value engineering (VE) proposals from contractors that save time or money over the as-designed solution. Agency management encourages the use of ABC when appropriate, and the local contracting industry has responded favorably. The Missouri DOT was one of the few agencies that dis- cussed innovations in substructure construction as a means of accelerating construction. It is using mechanically stabi- lized earth (MSE) walls as abutments to speed construction, shorten bridges, reduce costs, and allow for the use of con- crete instead of steel beams—all of which allow for a faster total project. Concerns were expressed about seismic and durability issues, and the department is working with local university partners for ABC assistance. Missouri has aggressively pursued implementation of alternative technical concepts (ATCs) on several smaller proj- ects, and more recently on a larger scale for the New Missis- sippi River Bridge Crossing in St. Louis. Essentially, the ATC process consists of an owner preparing a baseline design; any- one can bid on it as-is or can confidentially propose cost- and time-saving measures. Those measures must be approved before bidding, in which case the owner prepares an amend- ment to the contract drawings to reflect the contractor’s ATC for bidding purposes. ATCs are not necessarily an ABC method, but they provide an incentive for contractors to develop confidential cost- and time-saving innovations that will give them a competitive advantage. New Hampshire The New Hampshire DOT was interviewed as an agency with experience in ABC projects. The department has used precast elements extensively on several projects; and, specifically, the department received significant publicity for its replacement of the Main Street Bridge in Epping, New Hampshire. That project, in which a new bridge was completely erected of entirely precast elements in essentially a 1-week construction period, was noted as an ABC success. Even so, little follow-up to that project has occurred. This issue was raised in conver- sations with department staff. The response was that not enough people at the agency are interested in ABC as a proj- ect delivery tool. They don’t question the effectiveness of the project but have insufficient motivation to do it again. The University of New Hampshire continues to do research in the area, but the New Hampshire DOT does not have the same level of interest. Agency staff indicated that not many opportunities have arisen where acceleration appears justi- fied. They also reported that the Epping project was 2.2 times as expensive as a conventional bridge replacement and that until the cost premium comes down to 25%, they would have difficulty promoting ABC. The only serious impediment to the design of ABC proj- ects is the lack of ABC champions within the New Hampshire DOT. Among contractors, ABC is generally accepted; but when given the option, they seem reluctant to use it. Thus, when considered feasible and appropriate, projects are engi- neered to make use of ABC techniques, rather than leaving that decision to contractors. Contractors hesitate because ABC involves the use of new technology, and they want to keep their own employees working rather than subcontract- ing work to precasters. Very likely, contractors will use ABC when time constraints and disincentives are severe enough. New Jersey The New Jersey DOT provided an extensive interview focused mainly on the issue of project and agency impediments. The department has had some successful ABC projects, including the Hyperbuild initiative projects to replace several deterio- rated bridges near Trenton and a nearly completed project to accelerate the replacement of the Route 70 bridge over the Manasquan River. That project made extensive use of precast elements and was nearly a year ahead of schedule as a result. However, these are isolated experiences. The question was why ABC has not taken hold. The under- lying answer is that the department’s engineers and, in par- ticular, the project managers do not consider it a solution in many situations. That thinking relates to their past practices and impediments established by other units within the agency structure. The agency is generally risk averse. ABC is per- ceived as raising the level of risk associated with a project. The level of risk needs to be shown to be manageable for the con- cept to gain traction. There is currently no impetus for ABC. At the same time, there is no obvious opposition other than the inertia in the

248 organization’s practices. When the department has tried to accelerate projects, its own construction engineering depart- ment has been reluctant to support the schedule. Schedules are frequently lengthened on the basis of traditional prac- tices. Apparently, the traffic operations staff has allowed only short closure windows, which has the effect of prolonging projects and impeding ABC efforts. The New Jersey DOT incentive/disincentive opportunity on projects is tied to the computation of roadway user costs. These costs are typically thought to be very low and do not justify acceleration as a strategy. The department recognizes the need to study and update the user cost model and its application. The state has no mechanism to screen or choose projects for ABC. A ranking was done at some point in the past, but it was done by staff from an engineering perspective. No systematic approach is in place. Designers are reluctant to suggest innovative approaches. The concern is that project managers will not accept such pro- posals, so they have no incentive to be creative. The state does not procure contracts requiring innovative design and con- struction solutions. Thus, the same approaches are used again and again. FHWA engineers have provided limited support for New Jersey’s own initiatives to use prefabricated technologies or accelerated approaches. Another area discussed in the interviews pertained to removing obstacles. Department staff expressed the opinion that data on accident rates in work zones would be useful. If it could be shown that before construction, the rate was A, that during construction it rose to B, and that after construc- tion it returned to A, then that would be a compelling case for using ABC methods. Another way to promote ABC would be to provide data on lost-time accidents in the field (working around active traffic) versus construction that occurs in a plant, yard, or similar off-site facility, which would show a benefit to using ABC. It would also be useful if quality differ- ences could be demonstrated between projects constructed in the field and projects built with prefabricated elements. This includes bridges built off alignment and moved to their final location. New York The New York State DOT reports having completed approxi- mately 10 projects that could be considered as having used ABC methods. The department also states that though ABC is the exception rather than the rule, more and more ABC techniques are gaining acceptance, especially downstate in the region around New York City. For example, self-propelled modular transporters (SPMTs) were used in a project over the Van Wyck Expressway on Long Island. But the need for large staging areas is a problem in such a heavily developed environment, where ABC is most beneficial. Generally, ABC projects in New York are engineered to use ABC, but some- times the contractors submit substitute proposals using ABC methods. Hindrances include construction costs for ABC methods, especially the use of precast or prefabricated elements and off-site construction using roll-in methods. The New York State DOT also has some concerns about the durability of pre- cast component connections and joints. Furthermore, some local contractors resist the use of extensive prefabrication because of the large project share that is subcontracted out to specialists. Standardization would be less effective because the most beneficial applications of standardization tend to be less standard, such as projects in urban areas. Several pilot projects are under way that make use of ultra- high-performance concrete for joints between precast com- ponents, deck bulb tee beams for one bridge, and full-depth precast deck panels for another. The New York State DOT is also involved in ultra-high-performance concrete (UHPC) research investigating fatigue in precast element joints. North Carolina The North Carolina DOT has several ABC experiences includ- ing the reconstruction of seven bridges on Ocracoke Island, with crews working 24-hr days to replace the bridges in 90 days. Additionally, the Washington Bypass project is ongoing and employs an innovative construction gantry allowing for com- plete construction of a new viaduct from the top without any intrusion into environmentally sensitive areas. The department has project selection criteria for ABC proj- ects and spent some time in the interview process discussing the role of the Alternative Project Delivery Unit. The unit was specifically set up to work on design–build projects, VE propos- als, and alternative contracting mechanisms. The department typically allows for innovation in three ways: as a proposal from the contractor in design–build contracts, as an as-designed solution for special projects, and as a VE proposal. The depart- ment is currently exploring the use of MSE abutments as well as geosynthetic reinforced soil abutments as a means of expediting foundation construction. Texas A significant outreach effort in Texas was conducted by proj- ect team member Structural Engineering Associates. Various individuals from the Texas DOT Bridge Division and the San Antonio District were interviewed about ABC implementa- tion. Additionally, a major local contractor and precaster were included in the discussions. All of these people were asked about current ABC implementation status, obstacles to mov- ing forward, and concepts for future success. The opinions of the group collectively are expressed as follows.

249 As funding is currently structured, the owner has no finan- cial incentive to use rapid renewal methods other than staged construction. The Texas DOT districts are limited to using only 5% of the project cost for incentives. Also, no more than 25% of the road-user delay costs may be used for incentives. Although road-user costs are considered, the owner has no way of collecting any such savings. Therefore, if they spend additional funds to reduce road-user costs, they have fewer funds for other projects. That is a disincentive. One sugges- tion was for the federal government to create a mechanism that would allow owners to capture savings of road-user costs for use on other projects. For example, the mechanism could be a federal grant to the owner based on the value of the sav- ings. That would create the needed incentive to promote rapid construction projects. In Texas, most bridge projects involve existing bridges that are functionally obsolete but not structurally deficient. The most common reason they are functionally obsolete is that the bridge and roadway are not wide enough. In those cases, the roadway construction and not the bridge con- struction is on the critical path. It was noted that low-bid contractors may not have the ability to perform rapid bridge replacement. So, instead of selecting the contractor by low bid, a better method might be selecting the contractor on the basis of best value. Part of the best-value evaluation would be the experience of the contrac- tor on similar projects and the contractor’s approach to the construction. Project size is an important consideration for ABC. Because of the small to medium size of many candidate bridges, con- tractors will not become efficient with ABC methods during the short time frame of an individual rapid bridge replace- ment project. Additionally, precast components used for bridge substructures are only practical when lack of access makes the construction of cast-in-place components difficult or when there is sufficient repetition. Sufficient repetition makes the precast components more economical and their construction more efficient and faster. The only way to build overall effi- ciency is to build this capability over the course of several projects. For contractor efficiency, that means rapid bridge replacements must become commonplace. Bundling several bridge sites with similar requirements into a single construc- tion contract would make those bridges more economical. Finally, the contractor should not be forced to use a particular means or method. When incentives and disincentives are used, the amount must be large enough to pay for additional construction crews and for additional (or special) construction equipment needed to accelerate construction—and still result in profit. As an alternative, the department could consider milestones with no-excuse bonuses. If contractors are able to complete con- struction without any excuses, then they are awarded a bonus. Contractors will most likely submit bids assuming that they will not be awarded the bonus. Utah The Utah DOT has made extensive use of various ABC tech- niques for the past decade and has provided a substantial amount of information in various forms to the project team for review. The Utah DOT is unique in the level of support from the agency for the use of user costs as a strong consider- ation in weighing whether to use conventional or accelerated delivery methods. Though many states indicated some con- sideration of user costs, the Utah DOT has a project selection criterion that frequently leads to the decision to use ABC and that values user costs as real project impacts. Lack of resources, consideration of user fees, difficult materials supply issues, and other considerations have all pushed the department toward making ABC a standard practice by 2010. The depart- ment indicated nearly unanimous support at the senior man- agement level for undertaking projects that give strong consideration to minimizing user costs. At the present time, the Utah DOT is delivering its ABC program through a combination of design–build contracts and a method known as CM/GC (construction manager/ general contractor), both of which have proven successful. At the same time, the department is developing ABC standards for deck panels, precast substructures, new prestressed beam sections, and other details. Those standards will give the agency increased flexibility to let contracts using various mechanisms and to communicate its ABC intentions to the design and construction community. Once ABC standards become avail- able for engineers to use in the creation of as-designed ABC bridge plans, they will explore their use in more-conventional design–bid–build contracts. Agency staff believe that precast elements will offer an additional opportunity for cost savings in substructure construction. During its initial roll-out, the ABC program met with a fair amount of internal resistance, similar to the experience in New Jersey. Middle management presented the biggest obsta- cle, particularly the attitude that “we don’t do things like that around here.” Consultants and designers as well as the con- tracting industry were more easily convinced of the merits of ABC than were department staff. However, a sufficient core was willing to try new things in all parts of the business (department, consultant, contractor), so that a decision was made to move ahead with trial project implementation. During early phases of implementation, some additional reluctance emerged in the contracting community. The Utah DOT held a series of workshops and scanning tours to help learn from other agency practices. Some contractors have made successful changes to their business practices to com- pete in the ABC arena, while others are still holdouts. Successful

250 contractors have demonstrated a willingness to get into the pre- casting business. The projects let to date have demonstrated a 5:1 to 6:1 ratio of user costs saved to construction costs incurred. With repetition, costs have come down. Recent bridge project lettings indicate that full-depth precast decks are cost competitive and occasionally less expensive than tra- ditional cast-in-place concrete decks. Time and quality sav- ings have come as well. Although the Utah DOT has moved aggressively toward ABC implementation, some unanswered questions and areas of potential improvement remain. Those are generally tech- nical issues related to existing experiences and are not imple- mentation related. Concerns include issues such as seismic detailing, design consideration for structures to be moved, acceptable deformation limits during movement, a need for better specifications, and some additional concern about connection details and durability. Those issues notwithstand- ing, the department is aggressively moving forward with ABC as a standard delivery mechanism. Washington The Washington State DOT has employed ABC methods in some fashion on various projects. Those projects were com- pleted by using traditional design–bid–build procurement with some redesign of the structures to accommodate the ABC approaches. The projects have included complete bridge prefabrication as well as large-scale prefabrication of super- structure and substructure elements. In general, department staff believe that the use of prefabrication and ABC approaches did not have an effect on project quality but did have a benefi- cial effect on project safety. The department does not have a specific requirement to consider user impacts as project cost components but has used incentive/disincentive clauses to motivate project completion. Wisconsin Wisconsin is beginning to implement ABC practices, having recently redecked a major structure with full-depth precast deck panels. That first foray into accelerated reconstruction was a staged reconstruction of a bridge deck, and even from the first to second phases, the quality and speed of construc- tion demonstrably improved. The Washington State DOT believes this demonstrates that local forces can effectively execute a complex project and learn the proper techniques rapidly. Up-front training for others would be beneficial to better educate the construction community. Given that this process is new in Wisconsin, the levels of support and opposition are not well established. The support is perceived as lukewarm, with no strong opposition. Con- tractors have indicated that as long as they can make money, they are willing to participate. The department is exploring other opportunities for demonstration projects and is fund- ing research into precast substructure units. Second Owners Survey Results In June and July of 2009, several additional outreach activities were completed, allowing further insight into hindrances to the implementation of ABC methods, their causes, and their solu- tions. New surveys and interviews focusing on impediments and the acceptance of ABC within the industry were conducted with state departments of transportation, contractors, and fab- ricators. The owner questions focused on the following: • Experience with accelerated bridge construction (ABC); • The general level of acceptance of ABC in the state; • Whether the state engineers projects to employ ABC, or leaves that to the contractor; • Current impediments in the design and construction pro- cesses to greater use of ABC methods; • Whether availability of standardized elements and systems suitable for ABC and more durable connection details for prefabricated elements and systems would increase ABC implementation; • Ongoing or recent projects that implement ABC elements, in particular, unique, new, or innovative solutions; and • Ongoing or recent research related to the concept of ABC. Twenty-four state and federal agencies responded to the survey. The results are summarized by state. Alabama Alabama has completed one ABC project in the past 5 years. Despite successful ABC applications, the state is not ready to make the practice routine. The bridge projects that employed ABC techniques in the past were designed to do so; however, the contractor has the flexibility to modify the construction methods to ensure a better end product or a faster construc- tion schedule. Some of the impediments to large-scale of implementation within Alabama are a lack of manpower and elevated costs. The success of standardization was described as doubtful for typical bridges but may be successful for long structures that require substantial repetition of elements. Alabama is currently involved in the research and testing of four systems of rapid deck replacement on twin structures in the northern region of the state. California Caltrans has completed eight ABC projects within the past 5 years and is making a huge effort to include ABC methods

251 and techniques in its bridge replacement program. In Cali- fornia, ABC is considered to be only one part of accelerated project delivery (APD), which is a broader category intended to include all aspects of rapid project completion and to encourage everyone in the industry to take ownership of the ABC process. Steps have been taken to incorporate APD into Caltrans’s advanced planning process so that suitable project candidates can be identified, the ABC process can be stream- lined, and the required project funding can be secured. The acceptance of ABC has grown with the APD concept, appeal- ing to roadway engineers as well, and is received well when ABC is the best alternative and when funding is available. Seismicity is a major hindrance to the adoption of precast element technology in California, where cast-in-place domi- nates. More research on the seismic performance of precast bridge elements would be required before systems such as precast abutment systems could be adopted. As in other states with large urban areas, finding suitable staging areas is a problem, though early identification of project constraints could help with this problem. Cost is also an issue, as well as industry reluctance; but with the help of meaningful incentives, contractors may be enticed to use ABC methods. Standardization may make costs more economical, and that, in turn, would encourage all members of the industry to adopt ABC. Caltrans currently is using precast postten- sioned girders with integral bent cap connections on a wid- ening project and is engaged in several research projects involving seismic performance of precast bridge elements and connections. Delaware The Delaware DOT reported that it has some experience with ABC methods, having completed fewer than 10 projects in the past 5 years with ABC techniques. All of those projects were engineered to employ ABC. Some of the impediments the department describes include higher initial costs and contractors’ issues with extended hours and other associated costs—despite a generally good level of acceptance of ABC. Currently, the Delaware DOT is involved in projects that make use of innovative contracting methods such as A+B, A+B+I/D, and lane rentals. The department is also involved in projects that use precast elements, including the purchase of precast elements in advance. The Delaware DOT is not currently involved in any research pertaining to ABC. FHWA According to the Federal Highway Administration, several impediments are hindering the acceptance of ABC techniques among the various state departments of transportation. It reported that states are looking for design manuals and other aids to help them design and implement ABC—specifically, manuals such as the recently published connection details manual and a manual for designing prefabricated elements and systems. FHWA also reported that, even though many state DOTs consider cost a main obstacle to implementation of ABC methods, the costs associated with the Utah DOT’s ABC projects have steadily decreased over the past 2 years. The tendency for state DOTs and contractors to use cast-in- place rather than precast construction was also described as a problem; the solution is to introduce the industry to precast technology and demonstrate its profitability. Lastly, the lack of effective seismic connections for precast bridge elements must be addressed and is currently under investigation as an NCHRP project. Florida The Florida DOT has had a variety of experiences with ABC, having participated in the Graves Avenue Bridge movement with SPMTs and having completed several other projects within the past 5 years. While ABC methods have been worth- while for constructing certain projects, the practice has yet to be adopted as a standard, and typically traditional methods are used. ABC is, however, considered in the development of every project. The impediments hindering ABC in Florida are echoed throughout the results of the survey, as most of the states are experiencing some of the many hindrances listed. For exam- ple, limited space in highly urbanized areas is a problem for ABC using SPMTs when right-of-way is needed to construct and move a bridge into place. As this ABC method is most useful in precisely those areas, the lack of space is a huge issue. A possible solution is to purchase or lease property during construction, or require the contractor to do so. Another impediment is contractor inexperience with ABC methods; contractors need exposure to more information and oppor- tunities to familiarize themselves with ABC concepts. Main- tenance of traffic and phased construction is another issue as many sites have traffic constraints that need to be considered during the design phase. Public involvement is useful for gaining acceptance for the temporary full closure of a road- way. Uncertainties about a contractor’s methods for con- struction is another issue, as the Florida DOT lets its contractors choose their methods of construction by dictat- ing performance specifications rather than mandating the use of ABC. Common among most states is the issue of bal- ancing user costs with the additional costs of ABC, which is hard to justify when budgets are tight and many projects use standard construction practices. Also common among many states is the tendency for contractors to avoid subcontracting work to precasters, as they make their profits placing steel and concrete.

252 Georgia The Georgia DOT has some experience with ABC, having completed one such project in the past 5 years. The use of ABC methods needs to be required, and use of ABC is left up to the contractor in general. As with many other DOTs, the largest impediment to the implementation of ABC methods is cost; but the Georgia DOT does consider the standardization of pre- fabricated elements a way to lower costs associated with ABC. Illinois Illinois has completed a handful of projects with ABC meth- ods in the past 5 years. Bridge projects undergo a “bridge planning state” during which ABC is evaluated on the basis of site needs and cost-benefit analyses. The main hindrance experienced by the Illinois DOT is the expectation that ABC will cost more and that user costs are difficult to quantify. As with other DOTs, the Illinois department believes that stan- dardized elements would be useful in curtailing ABC costs. Iowa Iowa has extensive experience with ABC, having completed several ABC projects within the past 5 years. ABC is well accepted in Iowa; the state has completed ABC projects with innovative bridge research and construction/deployment (IBRC/IBRD) program funding and has spent its own money to accelerate projects when conditions require it. In Iowa, ABC projects are designed from the beginning to be acceler- ated, and contractors tend not to use ABC methods as value engineering proposals. According to the Iowa DOT, several impediments to ABC exist in the state, including low traffic volumes, contractor reluctance to adopt ABC because of the perception that it is less profitable, and contractor belief that ABC is too complex. Also, ABC incentives are low, which fails to attract contractor support. Upper-level management sup- ports using ABC wherever warranted; but in some cases, production-level engineers find designing for ABC to be slow and frustrating. Standard plans and shapes would help by easing the design process and saving money through reuse. Louisiana The Louisiana Department of Transportation and Develop- ment has extensive experience with ABC methods, specifically the use of precast elements such as span and cap segments, as well as float-out, float-in construction to erect long-span bridges over its many waterways. The agency also has experi- ence with precast flat slab bridges for projects off the federal highway system and reported that, though these bridges do not provide the service life of their cast-in-place counterparts, they are more easily constructed in remote areas. Recently, the agency used SPMTs during two 12-hour closures to replace an overpass damaged by over-height vehicles. The department reported that, while soil conditions within the state preclude them from precasting longer girder spans, standardization would be possible for shorter-span bridges. Contractors often request that cranes and crane mats be used on top of the struc- ture, so a standard element that takes into account crane loads would be ideal. The department would like to continue using ABC techniques in the future and has plans to use SPMTs to remove and replace spans in an upcoming project. Maine The Maine DOT has experience with ABC, having completed several projects within the past 5 years. The level of accep- tance of ABC within the agency is considered to be high. Cost is the largest impediment to ABC implementation in Maine, as it generally costs more to precast elements than to cast them in place. Standardizing elements could help lower costs of precasting as it might encourage fabricators to invest in stan- dard forms for bridge elements. Massachusetts MassHighway has not completed any ABC projects but is inter- ested in implementing pilot projects to build familiarity with ABC techniques. Because no ABC projects have been done in Massachusetts, one of the main impediments to implementa- tion is a lack of familiarity with ABC systems and techniques and how they will affect the construction process. As in many other states, a conservative cast-in-place (CIP) culture exists among contractors. But MassHighway believes that increased exposure through the completion of pilot projects will help overcome the tendency of contractors to use tried-and-true methods and hopes that more experience with ABC methods will diminish concerns about financial risk as well. Availability of standardized elements would be useful as that would reduce the need to develop custom details. In addition, the problem of a lack of familiarity could be offset by learning what standard- ized elements have been successful in other locations. Michigan Michigan has some experience with ABC methods, having completed projects that have been designed to implement ABC techniques and projects that have been accelerated as a result of the contractor’s input. The main hindrances to implementation are cost, constructability, and quality and performance issues. Life-cycle cost analyses with accurate accounting of the benefit to the public would be useful for addressing higher costs. Con- structability and quality issues will likely be addressed by the

253 experience of completing ABC projects in general. Standardiza- tion could make ABC methods more accessible to designers and would help contractors gain meaningful experience; both would help lower costs and improve quality in the long term. Nebraska While the Nebraska Department of Roads has not used ABC methods on any complete projects, elements of some bridge projects have been accelerated. There is no perceived need for ABC in Nebraska, so it is not widely accepted, and its applica- tions have been limited. In the cases where ABC was accom- plished through bridge elements, the bridge was designed to accommodate them; but contractors have also used discretion- ary methods to accelerate construction, such as using more man-hours. Primarily, ABC is hindered by higher costs. In addi- tion, contractors are hesitant to use precast elements because of the amount of work that would be subcontracted. Though Nebraska has urban areas that would be associated with higher user-delay costs, the user costs of lower-traffic roads and rural routes do not warrant the use of ABC. Standardization of precast elements is seen as a way both to lower costs and to increase the quality and durability of finished bridge projects. ABC bridge and research projects are currently under way in Nebraska, including the use of precast deck panels and heavy lifting of remotely assembled superstructure. New Hampshire ABC is generally accepted, but when given the option, con- tractors in New Hampshire seem reluctant to use it. When considered feasible and appropriate, projects are engineered to make use of ABC techniques, rather than leaving that deci- sion to the contractor. The only real impediment to the design of ABC projects is the lack of ABC champions within the New Hampshire DOT. Contractors are hesitant, as the practice involves the use of new technology, and they want to keep their own employees working rather than subcontracting work to precasters. Contractors are expected to use ABC when time constraints and disincentives are severe enough. New Jersey The New Jersey DOT has completed many ABC projects over the last 5 years, and acceptance of the practice is generally good within the agency. In the past, ABC projects have been engineered to employ ABC methods; contractors rarely rec- ommend innovative ABC techniques to achieve expedited construction. Several impediments were identified as having a negative effect on the success of ABC, including issues of sole sourcing and detours. Federal regulations and the pre- vailing mindset at the New Jersey DOT make the use of proprietary products difficult, but trying to write a generic specification does not allow for the procurement of the speci- fied item. Detours, on the other hand, are used only as a last resort, even when construction can proceed expeditiously; staged construction is preferred to allow the route to remain open. Contractors in New Jersey, as in other states, are reluc- tant to give up a portion of their work to subcontractors and fabricators. Unless the contract specifies time constraints, contractors will look for ways to complete jobs by using methods with which they are familiar. A suggested solution would be to allow a portion of a project to be constructed conventionally and have the remainder be precast. Further- more, if AASHTO and other organization would champion publications such as the FHWA prefabrication details manual (Culmo, 2009), the guidance would help encourage the use of ABC throughout the industry. Standardization would be a boon to the prevalence of ABC; and standardized elements and the combination of conventional and ABC methods for a single project would help more contractors accept ABC. Pennsylvania The Pennsylvania DOT has some experience with ABC, hav- ing used both precast ABC elements and more innovative approaches such as launching and SPMTs a few times over the last 5 years. ABC is considered on a project-by-project basis, but the additional costs from contract risk as well as life-cycle costs generally outweigh short-term advantages. Innovative ABC is usually at the contractor’s discretion unless the project would clearly benefit from ABC. In that case, the project is engineered to use ABC methods. Contractors are considered an impediment; they are generally unwilling to assume the additional risk associated with a technology with which they have no experience or that they have to subcontract, and that translates into inflated bids. Once ABC methods become more mainstream, costs and risk will likely decrease to the point where their continued use will be economical. Standardiza- tion would provide only limited improvement, as past efforts at standardization have not translated into profits for contrac- tors, who must subcontract work to fabricators, reducing the work for the contractor’s own forces. Currently, the Pennsyl- vania DOT is not implementing ABC methods in any projects but is involved in research in structural details that could be applied to ABC in the future. South Dakota South Dakota most recently completed an ABC project in 2001 where SPMTs were used to move a large steel truss super- structure to its abutments from a remote assembly location. In that instance, ABC was a necessity because the bridge was spanning a railroad yard, where closures and outages had to be

254 kept to a minimum. ABC is viewed favorably in South Dakota if project conditions warrant its use. As in many other states, South Dakota has relatively low traffic volumes, so user costs do not justify the elevated costs of ABC. However, there is sig- nificant interest in using ABC methods to construct jointless decks of adequate length for little or no increased cost. Tennessee The Tennessee DOT has made limited use of ABC techniques, having completed one project in the last 5 years that incorpo- rated ABC methods. Although ABC is always considered for a bridge project, it is not often used. Concerns that impede ABC implementation include questions about durability and quality of precast members, and connection issues— specifically attaching precast bridge decks to beams. With proven installation and serviceability records, standardized elements are considered useful for ABC within the state. Vermont The Vermont DOT has a good general acceptance of ABC and has completed five projects with ABC methods within the last 5 years. Projects are typically engineered to use ABC, but the department is considering projects that would contain per- formance specifications and leave the design of ABC details to the contractor. Because Vermont does not have high traffic, road-user costs are often too small to create meaningful incentive/disincentive clauses in contracts that would encour- age contractors to accelerate the construction schedule. Con- tractors tend to accept liquidated damages and overrun on time. The department would appreciate a way to apply sav- ings from ABC methods, such as the elimination of the need of temporary bridges, to incentive/disincentive clauses. West Virginia Within the last 5 years, five ABC projects have been completed in West Virginia. While the practice is generally accepted within the West Virginia DOT, the state does not have enough traffic volume to make it generally feasible for implementa- tion. The projects that were completed with ABC techniques were designed to use ABC and were the result of I/D clauses that were included to motivate contractors to develop ABC approaches. Impediments to implementation include an under- developed contracting industry when it comes to ability to perform ABC, and a lack of a precasting industry in the state. Furthermore, the state has few heavy lift contractors, and con- tractors like to keep the work local. If standards for ABC existed, contractors would likely make use of them. ABC spec- ifications for construction and sample contracts would be useful. And the department is also interested in methods that minimize environmental disruption. Wyoming Wyoming’s experience with ABC stems from the completion of several projects involving extensive use of precast elements and decked bulb tees for country road bridges. Wyoming has a good general level of acceptance for ABC, and it is used where appropriate, though Wyoming does not have the high traffic problems that some other states have. With lower traffic counts, the main impediment to the implementation of ABC is the jus- tification of the higher costs associated with ABC methods. There is interest in standardization, specifically seeing design standards that have been used by other states, which would likely lead to greater use of ABC designs within Wyoming. Owner Focus Groups To glean additional information about ABC within the envi- ronment of the departments of transportation, three 90-minute teleconference focus groups were held with representatives of several states. A total of 24 owner representatives participated in the focus group conference calls. The main topics discussed during the focus group meetings were the following: • Impediments to using rapid replacement methods; • Design for rapid bridge replacement; • Construction methods for rapid bridge replacement; and • Other issues states have encountered with ABC. Focus group discussion topics and key points made during the discussions are presented in the form of meeting notes and summaries. SHRP 2 Innovative Bridge Design Focus Group I 9:00–10:30 a.m. EST, July 20, 2009 Participants: Devin Anderson, Wayne Frankhauser, Maine; George Christian, Arthur Yanotti, New York; Paul Liles, Georgia; Sam Fallaha, Florida Question/Topic What are some of the impediments hindering the implemen- tation of ABC? Discussion Points New York: There is a higher [construction] cost; user costs and savings are not budgeted; hard money costs, so the additional costs must be worthwhile. Near New York City, a contractor proposed a precast deck system for ABC, but the New York State DOT—trying to save money—declined.

255 Georgia: There was a Highways for LIFE project that used ABC, but the contractor said it could do it in the same amount of time with standard methods (i.e., cast-in-place) despite time requirements. Maine: User costs and indirect costs are the main issues. For lots of fast-track construction, detour length is a big factor for deciding to use ABC. ABC may cost more, but it might not cost the overall project as much when factoring in building a tem- porary bridge and long detours. We have used precast abut- ments on piles, but the precaster was too slow and the contractor used CIP to make the schedule. We have used box beams with precast abutments to complete a project in 30 days, also gave up the leveling slab, and placed the membrane directly on top with shear keys. Existing bridge with traffic was shut down for 96 hours. Question/Topic How is federal funding involved? Discussion Points Maine: The costs aren’t blown out of proportion, but they are not necessarily outside the parameters of a high bid on a proj- ect anyway. There is more risk to the contractor, but good contractors can handle ABC well. Georgia: We had to stop giving contractor weather days, which would allow contractors to sit and argue about the weather. Question/Topic What about A+B bidding? Discussion Points Maine and New York have used it. Maine uses it off and on, specifically for interstate projects such as the I-95 deck replace- ment of the northbound and southbound lanes. The contrac- tor was allowed to choose how many days it bid to do the work. Georgia used it only in emergencies. Question/Topic General CIP culture exists for DOTs and contractors. How does that play into ABC? Discussion Points New York: It’s a factor, according to contractors; they are wor- ried about subcontracting to precasters, because it is not put- ting their own people to work and lowers profitability. With precast decks there have been problems with unions; the ironworkers union complained because there was no deck to reinforce. Florida: Contractors feel they’re giving up part of their work to the precaster and regularly try to keep the work internal to them; they want to keep it that way. Similar experiences in Nebraska. Question/Topic How can we change that? Discussion Points Florida: It will change with time and persistence. This will have to happen, as over the decades, construction has gotten more and more efficient, as a result of gradual changes, not big steps. It just takes time for the culture to change and the contractor to realize that you don’t have to have your own forces do everything. Georgia: The contractors will gripe about changes for ABC, but if it’s work, they’ll do it. If they can do more ABC projects, they will do them, as there is still plenty for them to do. Question/Topic The Utah DOT is changing its culture, and essentially said it wants to build bridges like this [ABC] in the future, and to continue doing so with currently existing technology. It will take an institutional commitment from the states before con- tractors will fully commit to any new way of doing business. Discussion Points Georgia: It is still more expensive, though they (the Utah DOT) have a way of applying user costs and can justify them. Utah does not have as many deficient bridges, and when you have 10 bridges to build at a 10% premium, the money spent on ABC could finance the construction of another bridge. Furthermore, SPMTs are expensive, and other states do not factor in user costs. SPMTs will likely be used with high- profile cases in Georgia. New York: There have been problems with precast systems, specifically with their joints and connections. On the Gowanus Expressway (New York City), they tried many systems, and what they found to work best is a CIP deck with accelerated cure. Georgia: CIP offers more flexibility, an example of which is when footings were built a bit higher by a foot, and the deliv- ered precast columns did not fit. They ended up switching them out, but in the process created many other issues. CIP would have been more flexible.

256 Question/Topic Do you have any issues pertaining to design for ABC? Discussion Points Georgia: The problem of precast connections is a big issue, but the FHWA connection manual is good and engineers at the Georgia DOT are finding it useful. Maine: ABC requires designers to spend more time on site because when you put a contractor into a time-restricted situation, the designer needs to have quick turnaround for answering questions. Question/Topic Do you see a need for standardized elements for ABC? Will this promote greater use of ABC? Discussion Points Florida: Currently, there are standards for everything, and once preferred rapid details are developed, the design/construction community will be more willing to use ABC. If a consultant wants to design for ABC, there is reluctance to use something that has not been used in the past. The Florida DOT is cur- rently in the process of developing preferred details. New York: Standardized connection details. The recent FHWA publication (Culmo, 2009) went a long way in promoting that. Question/Topic Would a similar manual for elements and systems be useful? Discussion Points Maine: One of the things we found most important is that designers have to work more closely with the construction peo- ple and pay more attention to detail on things that people are not used to doing and are not comfortable with. A lot of design people are not field people, so communication between design- ers and those in the field is critical. Question/Topic Do you feel that each state will need to have standard details, or can things be more alike among the states? Discussion Points Florida: If nothing else, the culture expects each state to have its own standards. Developing standards region by region may be a good idea. Having additional coordination is not easy but, if it is achievable, would probably prove helpful and productive. Question/Topic PCINE, with the NEXT beam, and a design manual (not a standard) for ABC, provides guidelines for using precast con- crete systems, and there may be openings for similar regional approaches. Has this been used in Maine or New York? Discussion Points Maine: I am not familiar with the particular document, but Maine is a member of the PCINE committee. Massachusetts plays a significant role. The NEXT beam is going to be used on a recently bid project, chosen by contractors over bulb tee. The advantage of the NEXT beam is that it has a larger deck area and is almost wide enough to hold a lane of traffic. Question/Topic Substructure accounts for 60% to 70% of construction time, and not a lot has happened through ABC in that regard. Discussion Points Maine: Pile substructure and precast abutment pieces are being used. If formwork is done ahead of time, reinforcing steel is expedited, and normal 14-day curing standards are relaxed in favor of a strength-based specification (maturity testing), it is possible to set superstructure on top of substructure in 1 to 2 days. This allows a contractor to cast its own abutments rather than subcontracting them out, but the contractor must be ready to move big pieces quickly. Rapid construction doesn’t have to mean precast. Question/Topic Among construction issues, what works well, etc.? Discussion Points New York: New York is using decked bulb tees and UHPC to close joints and experimenting with it between precast com- ponents, with good results so far. They are involved in fatigue testing at Turner–Fairbank (Highway Research Center). Maine: Maine is using new products, such as the Hillman beam, an FRP shell with a very thin arch inside the shell and high-tension strands in the bottom of the shell. They are extremely lightweight and can be installed with just a boom truck. They weigh 33% of a steel beam after you pour concrete.

257 The University of Maine in Orono has tested it to failure, and it performed exactly as predicted. Maine also has a “Bridge in a Backpack” concept that involves tubes of FRP filled with con- crete set in place, and uses FRP decking filled with concrete. Currently, there is a movable bridge that is to be replaced with FRP decking, built off site, and moved into place. Florida: There is an NCHRP project being done by Cathy French at the University of Minnesota, investigating the dura- bility of precast connections, and they are looking forward to conclusion of that research. Fast Track is design–build, but I cannot comment on how it’s going or what’s happening. Question/Topic Anything else? Discussion Points Self-consolidating concrete has been useful, especially when you can’t use a vibrator and it’s got to take care of itself. It has been a huge success and has not demonstrated any problems with shrinkage or creep yet. Georgia is currently involved in research. SHRP 2 Innovative Bridge Design Focus Group II 11:00 a.m.–12:30 p.m. EST, July 20, 2009 Participants: Lloyd Wolf, Texas; Ralph Anderson, Illinois; Anne Rearick, Indiana; Norm McDonald, Iowa; Joe Campbell, Dan Dorgan, Minnesota; Ed Wasserman, Tennessee Question/Topic What are some of the impediments hindering the implemen- tation of ABC? Discussion Points Minnesota: There are a couple of impediments. Funding is one as most of the jobs have cost some extra money. In Min- nesota budgets are set up so that the eight transportation dis- tricts have [only] so much to spend on projects, so they must seek additional funding if ABC will cost more. IBRD funds helped provide incentives. Right-of-way becomes an issue; Minnesota has been looking to use SPMTs which require available right-of-way. Generally, it should be used in a high- volume, urban area to be most effective, but these are the same areas without excess right-of-way. So SPMT use is very limited. Planning is a 4-year program, therefore education on how to use ABC processes is important for the planning process. Texas: So many projects involve a lot of roadway work, usu- ally widening if replacing bridges. Typically a project starts much earlier than just the bridge work, and when using phased construction, ABC is not needed. When a long detour exists, ABC can be used and can offset the costs of repairing a long detour route. Often, phased construction eliminates the need for ABC. The Texas DOT can put time limits on work but can’t dictate a contractor’s means and methods. Indiana: There is significant resistance from contractors. Texas: Some contractors prefer to do their own precasting. Precast prestressed fabrication requires plant certification, but precast bent/abutment caps use conventional reinforce- ment, so the contractor can precast elements in its yard, and the DOT will inspect. Tennessee: There are not many impediments, but it is not used much. Sometimes ABC is not going to be as easy as one thinks. They have used precast elements on the interstate near Knox- ville, but they didn’t use any of the details. The SPMT “thing” has been overblown: it has to be a highway crossing or a major river that allows for barge float-out/float-in, so it cannot be used everywhere. Indiana: ABC is always thought of as building a bridge some- place else and moving it into place. Tennessee: It is not feasible to replace many bridges in 24 hours. The concept can work, but the situation has to be perfect. Using precast footings and pile sections, a bridge can be built in weeks if everything goes well. Texas: Similarly to the work in Tennessee, earthwork and pav- ing might take a bridge off the critical path; and weather is a factor. If earthwork and paving could be accelerated, ABC benefits would be greater. Question/Topic How much of a factor is the precaster’s ability within a state? Discussion Points Tennessee: There is no reason to go to a precaster, as the more the contractor does itself, the more money it makes. Unless precast is posttensioned or prestressed, there’s no need for a precaster. Minnesota: Contractors have precasted caps off to the side of the project. When dealing with fabricators, some issues are lifting capacity and shipping from a plant. Tennessee: Using a full-depth precast slab, it is hard to get hori- zontal shear capacity, and it becomes an issue of making full- or half-width pours (half are preferred). The biggest impediment is coming up with a durable, quick deck with few connections.

258 Texas: Some CIP allows for better control of curve. Tennessee: Posttensioning is a problem. Indiana: There is agreement that posttensioning is a concern. It is not done a whole lot, and the ability to keep people trained and inspection staff available is lacking. Texas: There has been success with the “parking garage” detail, where edges are beveled to form a V groove and there are weld plate and grout channels. By using this method, they have avoided posttensioning decks. It has been used on bridges with 15,000 ADT, with observed conditions over a 6- to 7-year period. Question/Topic What about modular systems of sub/superstructure? Discussion Points Tennessee: There has been no trouble with that. Seismic connec- tions are a problem with modular construction for substruc- ture. There has been success with simple span made continuous for live load. We have built several bridges with this method and used splice plates to make it continuous for dead load. Tennessee: There is a manual being made for Utah to stan- dardize pier caps and columns. Iowa: Too many steps that are time dependent were hurting the acceleration part of the project for half-width full-depth panels with overlay (on 24th Street). Question/Topic How was ABC done in Iowa? Discussion Points Iowa: Most of these were done as innovative bridge projects with IBRD research money, and the state can usually get some partners with research money. There is still a premium. Tennessee: Unless the deck bulb tee system is used, one can crowd tee beams together with a narrow spacing to save on deck. Texas: There has been success with precast deck panels, and they are now working on a precast overhang. Tennessee: It is better to have a monolithic, well-cured slab than to have many splices and connections. It provides better durability and a better ride. Texas: Precast caps are a success with repeatability, and work is currently under way on a set of standards for precast cap connections. This has been used on approximately 20 jobs. Iowa: They have used steel piling and set precast abutments on top. Texas: They have welded connections cap connections and prefabricated a wing wall as an extension of the back wall. Illinois: There is interest in other somewhat standardized details, while they are trying to go forward with elements and connections. They find that user costs cannot be calculated effectively, and there is no convention to do so. Question/Topic How does support for ABC vary across the various levels of their agency? Discussion Points Tennessee: Those on the public relations side and in upper management who want to minimize traffic disruption are not thoroughly considering what it takes to build a bridge of good quality and durability. The user cost issue is real, but if it costs a third more to do ABC, the state is not recouping that extra third. Question/Topic What about detours and how they may affect the choice of ABC? Discussion Points Indiana: They are not a problem. Texas: There has been some success when the detour is large and access to emergency services is cut off. Illinois: Is there an effort, nationally, to address this lack of communication between all echelons of staff? If we could summarize the costs but highlight the advantages, it would be useful for some of the other bridge engineers. Tennessee: ABC is not going to be magic, nor is it going to work for many sites, such as stream crossings. Texas: Another issue is how to set up contracts to facilitate ABC. Minnesota: With regard to funding issues, they are consider- ing setting aside funds to encourage districts to use ABC as an “incentive pot.” Question/Topic What does it take to bring down the costs of ABC? How do we make it economically viable?

259 Discussion Points Texas: It costs the contractor more to build it faster, so we need to figure out how to set it up so that it takes fewer resources to accomplish. Tennessee: If it is a viable system and is economically advanta- geous, the marketplace will discover it. In the end, it only matters that disruption to the public is mitigated. Question/Topic How about A+B bidding? Discussion Points Tennessee: It has its place, but B costs might be unrealistic, as the DOT won’t get a rebate from the public. Texas: Disincentives get thrown into the bid, and the DOT ends up paying for it. Illinois: Illinois has had involvement with A+B bidding and finds it helpful, but it puts a lot of pressure on a small staff. Therefore, consultants would be helpful for the state. Question/Topic Do you have any innovative projects or research in the par- ticipating states? Discussion Points Minnesota: Minnesota is currently conducting research as a follow-up response to the 2004 FHWA scanning tour, spe- cifically using the Poutre Dalle inverted-tee system with a CIP pour. Tennessee: Seismic connections for substructure elements are currently being researched. SHRP 2 Innovative Bridge Design Focus Group III 1:30–3:00 p.m. EST, July 20, 2009 Participants: Mark Leonard, Colorado; Mike Beauchamp, Paul Chung, California; Mark Elicegui, Nevada; Matt Farrar, Idaho; Greg Fredrick, Wyoming; Jugesh Kapur, Washington; Kent Barnes, Montana; Dave Fredrick, Arizona; Craig Shikes, Oregon Question/Topic What are some of the impediments hindering the implemen- tation of ABC? Discussion Points California: ABC is something that is currently being devel- oped and requires further research into technologies for seis- mic regions. There has been some education of business partners and promotion of ABC in California. Contractors in California are good and geared for CIP, but getting them into prefabricated elements is going to take some work. Nevada: Like California, contractors are good with CIP, but Nevada has no established precast industry, no certified pre- casters; so precast girders come from Arizona or Utah, and there is an extra expense associated with shipping. Wyoming: Wyoming is a rural state with a limited number of contractors and fabricators, so a lack familiarity with prefab- ricated elements has to be overcome. Cranes limit size and weight of installation. Recently two precast abutments that would have been welded to piling with a precast girder got changed to CIP. Precast is a benefit because you don’t have to get fresh concrete out onto rural roads. Washington: Seismic connections are the biggest concern. Tra- ditionally, Washington is a precast–prestressed state and would like to extend that to substructure, but the weight is an issue. Even with SPMTs, contractors are hesitant to share profit; and getting elements to the site is a problem. Washington has com- pleted a deck replacement using SPMTs. Arizona: 90% of all bridges are CIP on prestressed I-girders. Traffic control is a problem for Arizona, and detours cost a lot of money. There is not a lot of knowledge about ABC, so they are not sure if local contractors can handle implement- ing ABC. Oregon: Oregon has used ABC and has put some provisions in its design manual as a starting point. A challenge is that there are a lot more cases where it can be justified if user costs are taken into account, but the issue is how to take those into account; and those costs are not necessarily sav- ings from the highway budget. It is perceived as a benefit to the taxpayer, but you have to look at the big picture. Seismic performance of ABC elements is a concern, and similarly to Washington, 80% of the bridges in the state are made of pre- cast concrete girders. There is an aggressive trucking indus- try, which has ruled out CIP construction in most cases and created substantial vertical clearance requirements during construction. Idaho: ABC has been tried, but user costs and best value are not true cost savings. The bridge budget is strapped, so the problem is completing more expensive projects versus user costs. Where do you draw the line between true cost savings and user cost savings? When ABC is both appropriate and cost-effective, it is ideal.

260 Montana: Montana is another rural state, but it is trying to define a class of projects that is fit for ABC, as there is a use for ABC in a rural environment. As part of that process Montana wants to look at projects early on to see if they’re appropriate for ABC. There is an ABC project to replace several bridges upcoming. In the past, a 100% precast bridge was value engi- neered to 100% CIP. With limited detour ability, ABC will save money. Montana is looking hard at providing flexibility within the contract. Maybe lane rental or I/D contracting methods can promote rapid construction. Oregon: User cost consensus would be useful for putting into contracts, and contractors would have to show the savings in user costs to justify value engineering proposals. Colorado: A lot of time can be saved with precast deck systems. In urban areas, there is a worry about the corrosive resistance of bare decks, as well as their durability. In Colorado, there is no familiarity with precast substructure. Another impediment is the need to continue to think about innovative contracting methods that allow the contractor to come up with innovative solutions. Some of their greatest successes with ABC have come from contractor proposals. Question/Topic What are the challenges from a design production standpoint? Discussion Points Idaho: The new FHWA connection manual is useful, but transporting elements out to the site needs to be considered. There need to be practical, tested seismic details. Montana: One of the problems often seen is consultants with timelines detailing that we need to do a bridge project con- ventionally, when it is clear that the project is right for ABC. Montana is a seismic state and can work through most of it in most situations. California: Connections are the major issue; they need to be validated for seismic performance. There are standards for pre- cast girders and other elements, but one of the other design issues is the design–bid–build contracting scheme, and ABC has to be assumed with limited input from contractors. Suc- cessful projects occurred when the contractor was fully engaged with designers leading to good collaboration. They are very limited as to what can be done prior to bidding, because they can’t directly interact until the contractor is hired. Culturally, very comfortable with CIP prestressed box beam bridge con- struction; the culture is going to have to change. Oregon: Many of the best designers at the DOT have been lost to design companies in the private sector, and now some designers struggle even on projects where there are clear cut codes and standards. Wyoming: One of the issues from the design standpoint is standardization, but that too presents challenges: we can’t even agree on precast girder sections, tons of standard precast girders. On-site quality control is difficult; and there is a need to guarantee the same quality when precasting is done in the field as when it’s done in the shop. The industry is going to have to embrace ABC at the same time owners are, and there needs to be a driving force. Question/Topic Is there an industry push in the west for ABC techniques? Discussion Points Idaho: Idaho has had a couple bridges use SPMTs, including one under construction, and has found that SPMT use is not as big of a challenge as previously thought. Washington: The major impediment to ABC on the West Coast is the issue of cost. ABC is not perceived as a more economical way of doing things all the time. Precasting is probably more expensive than CIP, and SPMTs add more costs—while design- ers are being told to keep the costs down. It is hard to adapt to something that is radically different, and hard to justify more expense, unless there is an effective way to bring user costs into the equation. Question/Topic What is the current level of support for ABC? Is it increasing or decreasing, and what needs to change for things to get better? Discussion Points Colorado: There is a fairly high degree of acceptance both in structure groups and in regions for innovative ideas to decrease the time of construction. Traffic disruption mitigation is not necessarily just ABC. Structurally, interest in ABC is growing and doing a good job with recognizing opportunities. Oregon: The degree of acceptance has been pretty good but can probably be better. A trunnion replacement on I-5 was a success, and the public was happy with the short closure period. Acceptance must improve from a couple of stand- points: mobility, which seems to trump everything else (if a method minimizes disruption to mobility, people are willing to pay more), and environmental, because less environmental impact becomes the preferred option.

261 California: While we were promoting ABC in various districts, ROW [right-of-way], environmental, and traffic people were extremely interested in the applications of ABC to their respec- tive fields, and this led to a lot of increased interest. Washington: Washington is heavily motivated and has used precast elements, moved whole bridges on rollers, and used SPMTs. The state is currently engaged in research with the University of Washington to develop seismic connections and has formed a research partnership with CalTrans. Anywhere where they can, they will use ABC. Nevada: The interest is high in Nevada, primarily to minimize traffic disruption. Major bridges in Las Vegas have had success with segmental construction as Las Vegas has lower seismicity and higher traffic. To date the state has not completed any ABC projects; because of a lack of precasters in Nevada, precasting is not particularly cost-effective. Use of precast elements is inter- esting, and Nevada will be looking into it for the future. There are concerns with full-depth precast deck element durability. Oregon: They are currently doing research into full-depth pan- els, looking at durability. There are issues with concrete decks that use high-performance concrete; there have been cracking and shrinkage issues. They are concerned with two-part sand- wich panels’ delamination and are proposing full-depth deck panels with no overlay, extra thickness, and posttensioning to get durability. Research is still in progress, and next year they will do a trial project. Idaho: Management likes less interference with traffic and keeping the public happy, but they are struggling with a lack of funding. ABC is still perceived to be more expensive. Colorado: Acceptance is high among upper management, as long as the structure maintains the expected durability. Nevada: Similar sentiments as Colorado and Idaho above. Contractors Surveys First Contractors Survey Results Similar to the solicitation of owners, an electronic survey for contractors was also prepared. In contrast to the state survey, which was somewhat easy to distribute by using the list of SHRP 2 agency coordinators provided by TRB, solicitation of contractors was significantly more difficult. In the end, the assistance of the Associated General Contractors (AGC) in Washington, D.C., was sought; and it was able to distribute the request for responses through various state AGC chapters. Responses were sparse and uneven. Consisting of four pages of questions, the survey garnered 17 complete responses and 29 partial responses (submitted as complete), yielding 46 via- ble responses. The survey has 29 questions; as with the owners survey, questions are shown or hidden on the basis of answers, so only applicable questions are presented and answered. Questions Summary The first page of the contractors survey asks for information regarding a specific ABC project on which the respondent may have worked. Respondents who have no experience working on an ABC project are taken to the next page. For respondents with ABC experience, the survey poses questions similar to those asked in the specific project section of the owners sur- vey, but from a contractor’s point of view. Unlike the owners survey, these questions attempt to ascertain the contractors’ thoughts on ABC relative to a specific project, rather than simply to learn of a specific ABC project for the purposes of screening and further follow-up. The second page of the survey addresses various ABC ele- ments and techniques. The questions here are designed to help the research team learn what sort of limitations exist for the design and transport of elements, gather information about specialized equipment, and determine what types of contract documents and deliverables contractors prefer for ABC proj- ects. The third page of the survey asks questions on contracting issues to determine what procurement methods the contrac- tors like and dislike, which work best with ABC, and whether they are effective. The fourth page asks some closing questions regarding the future profitability of ABC projects and the changing role of the contractor. Space is provided for free responses and any other information the respondent feels would be applicable; and as before, the respondent is asked for contact information and whether or not the research team has permission to contact them with any further questions. Contractor ABC Experience When queried about how a project was accelerated, the most- common responses were that the project used the following: • Large-scale prefabricated elements (63%); or • Special lifting/hauling/moving equipment (75%). Most of these projects appear to use a combination of the two main ABC methodologies, by using special equipment to move prefabricated elements. Contractors indicated that they were motivated to employ ABC because the owner required it. When asked about the success rate of these projects, • 78% of the contractors indicated that they had some prob- lems (nonspecific) in the field; and • These problems could be traced to unclear or inadequate specifications (25%) or design by contractor’s engineers (13%).

262 The team was curious as to contractor opinions about the engineer of record providing information on assumed as- designed erection sequences. One of the premises of this research is that engineers will be contemplating potential inno- vative erection sequences on future ABC projects and design- ing the structure for at least one unique erection method. When questioned whether this information would be valuable to the contractor, 90% of the respondents indicated that it would. When asked a related question, specifically, would the contractors be receptive to an owner requirement that a spe- cific method of construction be used in ABC contracts, 56% of the respondents answered no, 44% answered yes. If agencies mandate a specific method of construction, the freedom of the contractor to develop the best solution is diminished, and that has the potential to limit the number of contractors able to bid on a certain project. However, as was the case with at least one agency the research team contacted, an agency might not spe- cifically mandate the use of a certain piece of equipment but instead require that the project be completed within a finite amount of time (an amount small enough that the only feasi- ble way to achieve the constraint is through the use of a certain piece of equipment). The contractor would then be at fault for choosing another method of construction should problems arise and the time constraint not be met; liquidated damages could then be applied. The survey also raised the issue of how contractors would react to a changing world of construction involving potentially costly methods of erection. When asked under what circum- stances they would invest in new equipment (lease or buy) spe- cifically to be able to complete a project using rapid replacement techniques, • 20% said that they would not consider purchasing new equipment at all; • 30% said they would consider it if the expected use was greater than one project; and • 50% said they would invest only if the owner committed to many projects. This information is consistent with comments heard infor- mally by the team from other contractors and from contractors who have participated in prior demonstration projects. The cost of projects will be excessively high when contractors believe that a serious initiative to change business practices is lacking. When asked whether they would positively consider such a pur- chase if bridge construction became more standardized and based on certain methods of erection to speed the assembly, 90% responded yes. That response affirms the need for solid owner commitments to distribute costs across many projects, thus enabling contractors to recapture investment costs. The question of contracting terms and fairness was also raised. Contractors indicated first that many forms of contracts have been used on their accelerated projects, sup- porting the notion that various procurement methods are suited for ABC projects and no single method is preferred. When asked if the method of contracting and the contracting terms were appropriate, 67% of respondents answered that the method of contracting was appropriate. The survey also asked whether contracts included appropriate incentives to accelerate work; 67% indicated that they did not. However, further examining those data yields some interesting obser- vations. For those indicating that there were appropriate incentives, all believed that design–bid–build is better for ABC projects, and all affirmed the contract also included meaningful disincentives or liquidated damages if the required schedule was not met. When asked for their preference as to contract method for ABC projects, 25% of the respondents chose design–build and 75% chose design–bid–build. Nota- bly, the results of this set of questions could be affected by the presence or absence of alternative delivery legislation in a particular state. Contractor Personal Interviews In addition to the electronic surveys of contractor opinions and comments on various aspects of accelerated bridge con- struction, contractors—or engineers who support contrac- tors on innovative projects—were interviewed by members of the project team. Names have been withheld as are most details that would identify the response as being from a spe- cific contractor. The discussion is divided into two parts: the first focuses on impediments to ABC implementation and the second focuses on potential new technologies or advance- ments that were discussed in the various interviews. ABC Implementation Concerns This section includes detailed information from four separate contractors, some of whom were interviewed multiple times, and two engineers who work in the area of construction sup- port for major contractors. EnginEEring Firm A Engineer A is a consultant whose background includes design services for complex bridge erection and who also has experi- ence in forensic engineering and construction error investiga- tion. This individual’s perspective is that the use of standardized designs prohibits innovation. Engineer A would resolve this problem with alternative contracting, specifically using contracting mechanisms that allow engineers and contractors to team up and give the client their best ideas. Such “best value” awards are effective in bring- ing innovative designs and construction technologies into projects. However, such integrated delivery isn’t a good fit for

263 all projects, and contractors who don’t have access to in- house or on-call specialty engineering will potentially be unable to bring innovation to small projects. In addition, the process for teaming designers and contractors as it is cur- rently practiced is not user-friendly. The cost of pursuing work is very high, and many small designers and contractors cannot afford it. Stipends and other methods for obtaining more bidders and better ideas across all sizes of projects are needed. Another issue Engineer A sees is a lack of commitment to new technologies and innovative materials and methods. The pace of innovation is too slow for it to be cost-effective. Part of the reason is risk. The concept of risk is easy to understand, but measuring and budgeting for the costs of risk or associ- ated benefits at the program level is much more difficult. If an agency agrees to commit to x number of bridges using a new technology, it needs a mechanism to account for the costs associated with early failures or inefficiencies that are likely to occur as the new innovation is brought on-line but that will disappear or be minimized in future projects. The long-term benefits may be clear, but the short-term costs may be diffi- cult to allocate or defend. Working through the learning curve and distributing the risks will require a coordinated effort among contractors, designers, and owners. A commitment to multiple projects or repetitive designs will be needed so that contractors can spread the cost of new equipment over sev- eral projects. EnginEEr B The engineering services team for Contractor A (see the fol- lowing section) was interviewed. This major national con- tracting firm has been involved in many fast-track projects on an emergency basis, as well as planned rapid replacements. The engineering team made several suggestions. To improve project administration, project managers should use alliance contracts, which allow designers to get contractor input early in the project. This type of contract is useful when a lack of scope definition or early project complexity makes the use of design–build contracts problematic. In an alliance contract, the contractor is brought into the project at the 30% design stage with a fixed-fee cost-reimbursable contract. The award is made on the fee, and the incentive to reduce costs is created by looking at profitability from a margin (percentage) basis. If the fixed fee is earned at a lower overall cost, the mar- gin, or return, is higher on a percentage basis, which financial backers like to see. Contractor A has successfully used alliance contracts on projects in Portland, Oregon. Design–build contracts are very effective when the short list includes contractors with engineering expertise or knowledge. In design–build, the field personnel can be in direct contact with designers, which expedites the construction process. For many such projects, the design-builder will self-perform complex structures and highway work but subcontract more routine work. This allows for a division of labor that maxi- mizes resources (including time) and capabilities. The size of the letting, the schedule, and the complexity of the project are all considered by large, sophisticated contractors when decid- ing on what work to bid. To be competitive, they have to be able to add value through innovation capabilities, financial strength, or speed. Incentive contracts are effective. They allow for competitive bidding without sacrificing the need for speedy completion. However, agencies that have contracts containing incentive language must be ready to staff the projects to meet accelerated schedules from their end as well. If agencies strictly enforced significant liquidated damages, projects would be done more quickly. Currently, many extensions are granted for insignifi- cant events (e.g., weather that could be worked through). ContrACtor A As described previously, Contractor A is a major national contracting firm that has worked on both fast-track emer- gency projects and planned rapid replacements. Several ideas emerged from the interview. Bridge designs for “workhorse” bridges can be standardized to allow for repetition and prefabrication. However, realign- ment (to prevent skew) and fill or excavation (to allow for standard span lengths) of many existing bridges may be neces- sary to create an inventory of standard bridges. For structural designs, the best place to start is probably with AASHTO gird- ers. The goal is not to design each bridge individually but to use repetitive design standards and adapt the conditions (alignment, span length, width) to the standard. Typical span lengths and abutment details, modular deck components, and prefabricated structural elements could be integrated to meet specific design needs for individual bridges. However, connec- tion details and other design issues (moisture intrusion, freeze– thaw protection, hydraulics) would have to be analyzed for each application. Another key design issue is to use a life-cycle framework for bridge design. Designers should consider how the deck, struc- ture, and substructure will be replaced should expansion or rehabilitation be required. Every replacement and rehabilita- tion cycle costs money; and rehabilitation cycles probably never restore a bridge to 100% of initial design quality. So if those costs can be accounted for in the planning and concept stages, the justification for more-expensive bridges that are more easily “replaceable” can be made. One of the major schedule constraints for current bridge rehabilitation can be utility relocation and coordination. Util- ity companies are critical project stakeholders but operate more or less independently from the project team. Allowable cut-over windows and down times drive many construction schedules, and missing a cut-over window can delay a project

264 by as much as 6 months. Any current bridge design (new or replacement) should incorporate plans to optimize utility relocation or maintain utilities. That might involve redundan- cies, secondary vaults, or creation of a grid to allow for rerout- ing. These design concepts will not necessarily help with current bridge work, but if the practice is started now, bridge work in the long term (20 to 50 years) will become easier. With regard to the design of new structures to facilitate rapid reconstruction, Contractor A noted that it is unrealistic to think that one or only a few technologies will become dominant. An array of solutions will be needed for different site constraints, soil conditions, bridge characteristics, traffic volumes, and so forth. ContrACtor B A vice president and an area manager for Contractor B, a major midwestern bridge contractor, were interviewed. They observed that the key to speeding the construction of bridges is to design them so that as many activities as possible can overlap. For instance, if piers could be built off site while pil- ing is driven and foundations are placed, then piers could be placed in a matter of days once foundations are completed. Beam caps could be fabricated off site with posttensioning ducts cast in. Beam caps could be placed as soon as the piers are set. Such overlapping, using off-site fabrication, would reduce 3 weeks of pier and cap work on a typical bridge to 2 or 3 days. This is consistent with the goals of ABC as executed with large-scale prefabricated elements and rapid on-site erection with conventional equipment. The process could be further accelerated by using prebuilt modular sections in lieu of off-site fabrication. The use of modular systems with standard designs is a proven method of accelerating bridge construction. Burlington Northern Rail- road uses standard plans and connection details with modular precast systems such that they can combine them in configu- rations appropriate to each project (e.g., abutment type X, span type Y, and foundation type Z). The individual precast modules can be ordered in bulk on basis of the upcoming con- struction program. Burlington Northern holds the inventory, paying at fabrication, not at placement. Real gains in project speed can be achieved by changing administrative processes to allow for contractor input during the planning and design phases. This is especially true as transportation projects become more complicated and agen- cies have to replace and rebuild, rather than focus on new construction. Value engineering after the bid slows the pro- cess down. A simple way to get contractor input at early stages of the project is to allow agency personnel and consultants to be in contact with contractors without disqualifying the contractor from subsequently bidding on the work. No real bidding advantage accrues from advising designers in early stages. This issue will become increasingly difficult to manage as more and more public owners and design consultants lose in-house construction expertise. The increasing complexities of projects, the frequent changes in construction markets, the predominance of integrated team delivery in the private sector, and retirement of current construction expertise are all con- tributing to the loss of construction knowledge on the owner– designer teams. The problem has been growing for some time, but has gotten dramatically worse in the last 5 years. An administrative innovation worth considering is the creation of expert panels or review boards that would be available to agencies to help with constructability reviews and to provide construction input during planning and design. The “expert witness–friend of the court” system works rea- sonably well in providing technical expertise to nontechnical judges and jurors; a similar model could be adopted for con- struction, with some system in place to ensure qualifications. Using more design–build procurement would speed up programs as well. On a recent long-span pedestrian bridge project, the job was readvertised as a design–build project after the original bids in the traditional design, low-bid award came in too high. For the design–build project, the contractor went through conceptualization, design, procurement, and construction in the same amount of time that the design phase took in the traditional method and for far less money than the original concept as it was engineered and bid. Another beneficial change would require a culture adjust- ment for some agencies. Some public owners consider the bridge builder as a value-adding, technically proficient part- ner in the process; but others still view the builder as a con- tractor that needs to be told what to do. If agencies want advice and input from contractors, they need be viewed as professional service providers, and then held accountable to those professional standards. ContrACtor C Contractor C operates under the philosophy that time, cost, and quality are the fundamental performance characteristics, and two of the three can be achieved on any project. Since qual- ity cannot be compromised, the trade-off is between time and cost. If agencies want to replace bridges faster, they will prob- ably have to pay more. Totally precast bridges are possible, but most contractors are currently operating their cranes at about 90% of capacity; so transformation to large-scale precast operations would require some changes in how equipment is used on projects within the industry. Contractor C has developed various proprietary systems and concepts to accelerate bridge construction. These include a proprietary system that eliminates the overhang brackets with special edge conditions for deck sections. This placement technology is proprietary and must be allowable in the specifi- cations before it can be used on projects. Contractor C has also

265 developed a top-down construction system that allows for bridge placement without the need for any ground-mounted equipment. This system minimizes environmental distur- bances and provides a more economical placement system on certain types of projects, specifically those with multiple long segments with site constraints. They have used this system on a 3-mile bridge system over wetlands in the eastern United States. The bridge elements do need to be designed for con- struction loads, not just final traffic loads, so the designer must be aware of the contractor’s intention to use such a system before designing the bridge structure and substructure. For this reason, a project like this is best suited for design–build where integration of these decisions is possible. In a design– bid–build scenario, with many options for construction, pre- suming such a system from the outset might result in an over-engineered structure if others pursue alternate methods of erection. Contractor C points out that many time-saving technologies are proprietary and not conducive to an open- bid, low-cost award procurement system. ContraCtor D Even in an ABC world, contractors need to be provided with an opportunity to gain a competitive edge over their com- petitors. Projects that have unreasonable or unknown risks will have that level of risk translated directly to dollars on bid day. The perception of risk limits potential interest in projects. The use of precast/prefabricated elements offer many advan- tages in an ABC context. They lower risks that are due to uncer- tainty, such as difficulties with labor availability or performance quality; they may mitigate poor access or site constraints and minimize many weather problems that can affect on-site con- struction. With precast/prefabricated construction, the bulk of the man-hours are spent in a climate-controlled predictable work environment and subcontracted out at a fixed price. There are additional benefits of self-control and pricing con- trol if the contractor also takes on the role of producer. Precast specifications are generally clear and rarely contested. The erection of these components is generally well understood and simple to execute. An important facet of ABC success is repeatability. With multiple applications, all contractor risks are lowered and costs are reduced commensurately. The fewer new operations that occur on any particular project, the more time can be used to improve existing processes. Accelerated projects can be profitable. These projects should always include incentive/disincentive clauses. In accelerated contracts, an advantage to the contractor is the speed of reve- nue recognition. However, a project that provides earning opportunity should not require a similar outlay or investment to earn the bonus. According to Contractor D, things that contractors gener- ally don’t like or that contribute negatively to project success include the following: • The use of fast-track scheduling when it is not needed; • Onerous specifications meant to make up for incomplete or poorly prepared plans; • Projects that are ineffectively communicated, including scope, scheduling, and phasing requirements and details on innovative details that might be used on future projects; and • One-of-a-kind designs that limit the possible reuse of forms, require new technology, have an unsure cost history, and generally require significant training of personnel. With regard to traffic control, agencies typically seek to min- imize traffic impacts—to limit closures, detours, user costs, and impacts on essential services. The result is inefficiencies for the contractor. Traffic closures are a dangerous field operation, and the resulting limited work windows are inefficient. Work is frequently shifted to less-productive shifts, and costs of cancel- lation are high. From both sides of the traffic control issue, the use of closures forces each side into an undesirable situation. ABC is an interesting solution in that it may benefit both sides of this issue. ABC Ideas and Concepts from Contractor Interviews The following ideas are a compilation of those offered up by the various engineers and contractors individually inter- viewed during this process. traffiC Closures Disruption may be reduced by rerouting traffic to local surface streets and working quickly within a completely closed road section. This approach speeds up the overall construction time. overheaD ConstruCtion New elevated lanes could be built down the median of exist- ing roadways by first closing the center lanes, then shifting traffic to the outside and working overhead. self-ConsoliDating ConCrete Self-consolidating concrete has been used by the Colorado DOT on bridge piers, but it may not have resulted in signifi- cant time savings. It did help speed construction somewhat but was not a major time-saver. ConCrete enCasement In composite designs, the use of “big steel” encased in concrete has not been used much but does show promise. Such designs may also be long-lived and require less maintenance.

266 stEEl shElls Encasing concrete in steel is an alternate approach to com- posite action. Piers and columns could use steel as stay-in- place forms to shield concrete, especially in high-impact areas. With conventional CIP concrete, rebar coverage can be compromised, and that is expensive and time-consuming to fix later. inCrEAsED EFFiCiEnCy with ConvEntionAl mEAns Conventional means and methods can still be used in an ABC situation. Contractor B has placed a 450,000-lb straddle bent and eight lines of girders during a single 8-hour road closure, including crane erection and dismantling during the closure period. Achieving such speed requires innovative means and methods by the contractor, but it is possible and can be com- pleted with traditional equipment. sElF-ProPEllED moDulAr trAnsPortErs SPMTs are useful in certain conditions but are not a cookie- cutter solution. They need to be employed more consistently (repetitive work) to become cost-effective. sliDing AnD lAunChing Many placement and positioning systems have proven suc- cessful, such as horizontal skids to move an integral, com- pleted bridge (deck, superstructure, and substructure) into place on caissons or some similar foundation system. This system is best suited for dry channel applications where skids can be placed adjacent to the bridge. A similar system using floats instead of skids can be employed for wet channel appli- cations. It is also possible to flood a dry basin or even create a basin to float a bridge into place. Pivot placement systems have been used, but many of them are single-use designs and probably not feasible for standard bridge designs. othEr sPECiAl EquiPmEnt SPMTs have their place, but cranes will probably be the stan- dard for the near term. Designs should be adaptable to a number of placement options. Customized equipment like launching gantries requires standard, repetitive design to warrant the initial capital investment. Agencies might be able to own the custom equipment and make it available to con- tractors on special bridge projects where it is warranted. An analogy would be the way load test frames are currently managed. DECk PAnEls Full-depth precast deck panels reduce construction time. Many such designs require connections between panels or between panels and beams, and the schedule is driven by the number of connections. Creating a box-out in the deck system and working in congested stud pockets is low-productivity, intricate work. Using a less elaborate design would reduce costs. Speed is also slowed by the need for a wearing course overlay to meet specifications. An alternative would be to set panels high and grind to tolerance, including the pavement grooving. That might eliminate a step. Larger pocket spacing to develop full- composite action while minimizing “small work” is another option. PArtiAl-DEPth DECk PAnEls Partial-depth precast panels that double as stay-in-place forms are simple and save time, but reflective cracking is an issue. PrECAst sEgmEnts The Victory Bridge in New Jersey uses precast footings, piers, caps, bents, and decks. Precasting accelerates construction, but one downside is that the substructure goes from light work to heavy work and that may restrict the number of bidders. Using precast segments allows the contractor to set a section of work in a day that might take 3 weeks with conventional reinforced, cast-in-place concrete with traditional formwork and false- work requirements. The transportation issues involving weight and geometry of large segments should be considered in designing the overall system. lightwEight ConCrEtE Lightweight concrete mixes can be used to lighten sections, enabling geometrically larger section placements by the same cranes. Postgrouting Use of postgrouted pier foundations has potential but is cur- rently not a time-saving technology because many owners are not open to innovation. Onerous testing and verification requirements for innovative technologies (such as postgrouted piers) slow down the project, eliminating the potential time savings created by the innovation. sEmiContinuous ConstruCtion Using threaded rods to make girders continuous is a good compromise between structural efficiency and construction speed. Threaded rods eliminate creep redistribution. From a construction viewpoint, it is best to have either simple spans or mechanical connections. stAnDArD PrECAst sECtions Standardization of sections is helpful in increasing productivity. Most major contractors have high-capacity cranes (250-ton) or can rent them easily, so designing each member of a section to weigh about the same at the high end of crane capacity would reduce the number of operations for a given bridge. In particu- lar, precast box girders work well for long spans.

267 ComPositE PrECAst ConstruCtion The Willis Avenue Bridge in New York City used precast boxes as so-called sacrificial forms, which also allowed for aesthetic features to be cast in. This process can have schedule benefits. ContrACtor limitAtions Smaller contractors will be more challenged to use renewal technologies because of capital constraints, inability to spread risk across multiple projects, and lack of access to engineering knowledge. However, some new designs can be implemented by small contractors. For instance, the FHWA 2004 scanning report discussed inverted-tee bridges with loop connections (the Poutre Dalle System) that could be placed and cast by small contractors. However, the test projects went well over budget, so cost may be a limiting factor for this design. ultrA-high-strEngth ConCrEtE It may be possible to combine ultra-high-strength concrete chemistry with geofoam technology to develop an expand- ing, high-strength concrete material that could essentially be spray-applied. Second Contractors Survey Results In June and July of 2009, several additional outreach activities were completed, allowing further insight into hindrances to implementing ABC methods, their causes, and their solu- tions. New surveys and interviews concerned with impedi- ments and the acceptance of ABC within the industry were conducted with contractors. Contractor questions pertained to the following topics: • What problems are typically encountered in the field on ABC projects? • Would the availability of standardized bridge elements and systems suitable for ABC encourage greater use of ABC and lower costs? • What are the optimal weights and sizes for prefabricated substructure or superstructure units? • For standardizing ABC, what weight limitations are sug- gested for large pieces to be erected? The results of these surveys and interviews are summarized here. Contractor 1 This contractor does not have much experience with ABC but is constructing a project that will make extensive use of prefab- ricated elements. For this job, mobilization is a problem, as the bridges are in remote areas. As a result, the prefabricated ele- ments will be in much smaller pieces than is desirable because of limitations on the cranes that have access to the site. Specifi- cally, a 150-ton crane is being used, and that capacity is the limiting factor in deciding how large precast elements can be. This contractor performs construction services on long-span and complex bridges, so the use of specialty engineers to check structures for movement or lifting is warranted. Contractor 2 This contractor has used ABC on precast culverts and on rail- road bridge replacements, specifically having employed pre- cast pier caps, abutments, box culverts, and superstructure sections. In this contractor’s experience, mobility is also a problem, as larger cranes require more space and delivery methods for large precast pieces can be complex and cause problems and delays. Therefore, this contractor prefers a site- specific design that acknowledges constraints, mobilization, and crane needs over a standardized design approach. In many cases the engineered ABC solutions resulted from col- laboration between the designer and the fabricator so that the site-specific access issues were adequately addressed in the design. Again, limits on the weights of precast structural ele- ments should be based on crane capacities. This contractor suggests using a 100-ton crane to move footings, columns, and cap beams, and a 200-ton crane for beam elements and superstructure modules—assuming the cranes can be mobi- lized given the specific site constraints of a given project. Contractor 3 Contractor 3 used ABC methods to completely demolish and replace an existing four-span bridge over an interstate with a two-span precast box girder bridge in 60 days. In this case, the owner required use of ABC because the bridge carried a major access route for local businesses. The contractor believes that the availability of standardized bridge elements would help lower construction costs and allow fabricators and contractors to work together and develop an assembly-line approach to construction. As with the other contractors interviewed, Con- tractor 3 sees site access as a large problem and the use of larger cranes as more expensive. This contractor suggests a reason- able maximum weight of precast bridge elements is 100,000 lb for footings, columns, and cap beams; 125,000 lb for beam ele- ments; and 150,000 lb for superstructure modules. Contractor 4 This contractor appears to use the ABC methods of precasting fairly regularly without major problems. The contractor’s use of ABC methods was motivated by time and cost, as well as the quality of precast items, which is higher than some CIP methods. The typical problem of using precast elements to

268 accomplish ABC is “getting the engineering and detailing right.” Having a senior designer with decision-making ability on site to answer questions quickly would help. With regard to standardization, several elements have the potential to be stan- dardized easily: precast concrete box beams, precast concrete barriers, and precast vertically posttensioned pier elements. Foundations and pier caps may not be as easy to standardize as other elements, so this contractor suggests having a menu of options that could be used in various situations, such as differ- ent soil types and site constraints. This contractor reports that lifts between 50 and 100 tons are becoming quite common and might be a good range for prefabricated bridge-element weight limits on standard bridge replacement projects. Contractor 5 As a Japanese contractor, this firm’s experiences with ABC dif- fer significantly from those of contractors based in North America. In Japan, ABC is seen as a method not for replacing deficient structures but for mitigating heavy traffic jams at specific at-grade crossings by building viaducts and bypasses rapidly. Unlike those in the United States, Japanese contract- ing methods generally do not contain incentive/disincentive clauses or liquidated damages that encourage the contractor to expedite construction; for that reason ABC in the North Amer- ican sense is not common. This contractor believes that each ABC project requires a site-specific design because each project must satisfy different site constraints, such as working space, storage yard, and availability of erection equipment. Because Japan has highly congested and dense urban areas, Contrac- tor 5 suggests that prefabricated units with a maximum weight of 30 tons are feasible for installation within the tight con- straints of a typical Japanese metropolis. Given that Japan is an extremely seismically active region, this contractor has several options for foundations and connections between superstruc- ture and substructure that could be of some use to precasting efforts in states such as California and Washington. Contractor 6 This contractor has experience with ABC projects, having employed full-depth deck panels and precast abutments and approach slabs. Some problems have arisen with these proj- ects, such as inadequate time for shop drawing approval and fabrication and availability of special materials. The contrac- tor suggests that future ABC projects take these possible delays into account lest the full speed of ABC not be achieved. Con- tractor 6 feels that standardization of ABC bridge elements would be beneficial and could help lower costs. Precast con- crete abutment blocks have been particularly successful, stacked 11 high (33 ft) and posttensioned to the footing. When lead time is provided to ensure the availability of fabricated blocks, a 300-ft abutment can be erected in as little as 5 days. Contractor 7 Contractor 7 has extensive experience with ABC and is cur- rently involved in a project that uses innovative automated machinery to accomplish ABC with precast elements. When using ABC, speed of construction is a factor, but as one proj- ect is a 3-mile bridge over wetlands, environmental impact mitigation is also a factor. One problem encountered when using ABC methods has been owner reluctance to embrace unproven or unfamiliar methods; for an ABC project to be successful, flexibility on the part of the owner is a necessity. Standardization as a concept can be useful for lowering con- struction costs, but imposing standard solutions may stifle innovative solutions. This contractor believes that the size and weight of prefabricated elements does not preclude their use in an ABC project, and every option should be studied and analyzed for efficacy in a given project environment. Bridge-element weight limits suggested by this contractor are 40 to 50 tons for an individual unit, and up to 1,200 tons for modular prefabricated units. Contractor 8 This contractor has used stay-in-place concrete form panels to achieve ABC, due to both time and access restraints. Resis- tance to change by local officials has been an impediment to ABC use. Some have expressed concerns about long-term maintenance; education about the method helps relieve those concerns, but works only if “the student is willing to learn.” Contractor 9 This fabricator has done precasting for several emergency proj- ects that required the use of ABC to open structurally sound bridges as quickly as possible. Because of varying substructure and superstructure components, this fabricator believes ABC projects require site-specific designs. Maximum limits for the weights of prefabricated components suggested by this fabrica- tor are larger than those suggested by contractors: 190,000 lb for all types of components when being shipped over land, and 400,000 lb for all types of components when movement over water is an option.