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29 Agency Perspectives and Practices for Constructing or Rehabilitating Concrete Pavements Under Traffic This chapter describes the specific practices used by transportation agencies in the United States to construct or rehabilitate concrete pavements under traffic conditions. The agency-specific construction and rehabilitation practices and experiences were compiled from a survey of trans- portation agencies and follow-up interviews with agency personnel. The synthesis survey ques- tionnaire, disseminated through the AASHTO Highway Subcommittee on Construction, focused on project planning, project management, MOT, construction, materials, and other aspects. Survey Participation The survey questionnaire was distributed to highway construction engineers at 52 transporta- tion agencies (all 50 states, the Illinois Tollway, and District of Columbia), using a web-based online survey tool. Forty-five survey responses were received, which included five agencies (Maine, Montana, New Hampshire, Alaska, and Rhode Island) that reported little to no use of concrete pavements in their respective states. The survey sought information on agency practices and experiences pertaining to the following topics: â¢ Maintenance of traffic, â¢ Materials and design, â¢ Paving equipment and concrete placement, â¢ Paving operations, â¢ Project management, â¢ Project delivery, â¢ Project procurement, â¢ Payment methods, â¢ Project-related communications, â¢ Public outreach, and â¢ Motorist information. Appendix A shows the survey questionnaire with agency responses, and Appendix B lists the agency respondents. (Appendices A and B can be found at www.TRB.org by searching for âNCHRP Synthesis 530.â) Concrete Pavement Construction To obtain a better perspective of the concrete pavement construction and rehabilitation prac- tices used by various transportation agencies, the survey respondents were asked to identify the types of concrete pavements constructed or rehabilitated. The agencies were also queried on C H A P T E R 3
30 Construction and Rehabilitation of Concrete Pavements Under Traffic the frequency of construction or rehabilitation of concrete pavements, with the construction/ rehabilitation frequency evaluated using an adjectival rating scale of âneverâ to âvery frequently.â Over 50% of the survey respondents (23 out of 45 agencies) indicated that they frequently or very frequently constructed JPCP, and another 27% (12 out of 45 agencies) stated that they occasionally constructed JPCP. Some agencies, such as the Alaska Department of Transportation & Public Facilities, rarely used JPCP, with only two minor urban street JPCP rehabilitation proj- ects in the past 20 years. The construction and rehabilitation of CRCP was far less common, with only two agencies reporting frequent use. About 29% (13 out of 45 agencies) reported that they occasionally used CRCP. Some agencies reported that, although they no longer construct CRCP or jointed reinforced concrete pavements (JRCP), they occasionally have to repair, rehabilitate, reconstruct, or overlay these types of pavements. Forty-four percent of survey respondents (20 out of 45 agencies) reported that they constructed or rehabilitated asphalt over concrete composite pavements frequently or very frequently, and another 18% (8 out of 45 agencies) occasionally constructed or rehabilitated composite pave- ments. Precast concrete pavements were the least-used pavement type, with 63% (27 out of 43 agencies) noting that they never used precast pavements. Usage of precast pavements among the remaining agencies varied from very rarely to very frequently. The most commonly used type of concrete overlay was unbonded overlays, with four agencies constructing them frequently and another 25% (11 out of 44 agencies) constructing them occa- sionally. Three agencies frequently or very frequently and another four agencies occasionally construct bonded concrete overlays. Some agencies have stopped constructing bonded concrete overlays due to poor performance on past projects. Five agencies occasionally constructed thin or ultrathin bonded concrete overlays of asphalt or composite pavements. Table 8 presents the types and frequencies of concrete pavements constructed or rehabilitated by the surveyed trans- portation agencies. Concrete Pavement Rehabilitation/ Restoration Techniques Of all the techniques listed in the survey, full-depth repairs (including precast repairs) was the most frequently used option, followed by partial-depth repairs. More than 68% of respondents (30 out of 44 agencies) frequently or very frequently performed full-depth repairs (including Types of Concrete Pavements Number (percentage) of Respondent Agencies Using a Pavement Type Never Very Rarely Rarely Occasionally Frequently Very Frequently Responses Jointed plain concrete pavements 4 8.9% 6 13.3% 0 0.0% 12 26.7% 15 33.3% 8 17.8% 45 Continuously reinforced concrete pavements 19 42.2% 9 20.0% 2 4.4% 13 28.9% 2 4.4% 0 0.0% 45 Composite pavements (asphalt over concrete) 4 8.9% 7 15.6% 6 13.3% 8 17.8% 10 22.2% 10 22.2% 45 Precast pavements 27 62.8% 11 25.6% 2 4.7% 1 2.3% 1 2.3% 1 2.3% 43 Bonded concrete overlays 2045.5% 12 27.3% 5 11.4% 4 9.1% 2 4.5% 1 2.3% 44 Unbonded concrete overlays 17 38.6% 10 22.7% 2 4.5% 11 25.0% 4 9.1% 0 0.0% 44 Thin/ultrathin bonded concrete overlays of asphalt or composite pavements 15 33.3% 18 40.0% 7 15.6% 5 11.1% 0 0.0% 0 0.0% 45 Table 8. Types of concrete pavements constructed or rehabilitated by highway agencies.
Agency Perspectives and Practices for Constructing or Rehabilitating Concrete Pavements Under Traffic 31 precast repairs). Another six agencies occasionally performed full-depth repairs. More than 46% (20 out of 43 agencies) frequently or very frequently performed partial-depth repairs. Another 12 agencies occasionally performed partial-depth repairs. Forty-one percent (18 out of 44 agencies) frequently or very frequently performed diamond grinding of the concrete surface, and another 43% (19 out of 44 agencies) performed it occasion- ally. Agencies occasionally performed dowel bar retrofit and slab stabilization, with five to six agencies performing them frequently or very frequently. The least frequently used rehabilitation/restoration techniques were crack stitching, retrofit installation of longitudinal edge drains, and lane replacement, although many agencies occa- sionally perform these activities. Table 9 lists the types and frequencies of the concrete pavement rehabilitation/restoration techniques used by the surveyed agencies. Maintenance of Traffic A key aspect of construction and rehabilitation of concrete pavements under traffic is manag- ing the work zone, particularly as it pertains to MOT. Agencies have used a variety of techniques and tools to accommodate traffic while constructing concrete pavements. Thirty-nine agencies responded to the survey questionnaire regarding MOT planning and implementation prac- tices. These results are shown in Figure 3. The most commonly used MOT practices for the construction and rehabilitation of concrete pavements under traffic were construction of temporary pavement [85% (33 out of 39 agen- cies)], portable signs in the work zone [85% (33 out of 39 agencies)], and driver advisory signs at the project ends [82% (32 out of 39 agencies)]. Sixty-four percent (25 out of 39 agencies) of the survey respondents permitted use of multiple work zones for each construction activity, 59% (23 out of 39 agencies) specified construction limits (days/mile) on the contract, 54% (21 out of 39 agencies) allowed subcontractors to work within the same work zone as other contractors on either side of the roadway (when work equipment did not encroach on the traveled way of either lane in the project location), and 49% (19 out of 39 agencies) permitted multiple work zones for sawing and patching operations. Fewer agencies preferred some MOT activities such as staged (rolling) detours [38% (15 out of 39 agencies)], permitting work on shoulders across the road from a lane closure to proceed at Types of Concrete Pavement Rehabilitation /Restoration Techniques Number (percentage) of Respondent Agencies Reporting Use of a Specific Rehabilitation/Restoration Technique Never Very Rarely Rarely Occasionally Frequently Very Frequently Responses Slab stabilization 37.0% 11 25.6% 9 20.9% 15 34.9% 5 11.6% 0 0.0% 43 Partial-depth repairs 5 11.6% 4 9.3% 2 4.7% 12 27.9% 13 30.2% 7 16.3% 43 Full-depth repairs (including precast repairs) 3 6.8% 0 0.0% 5 11.4% 6 13.6% 18 40.9% 12 27.3% 44 Load transfer restoration or dowel bar retrofitting 7 16.3% 6 14.0% 5 11.6% 19 44.2% 5 11.6% 1 2.3% 43 Diamond grinding and grooving 3 6.8% 2 4.5% 2 4.5% 19 43.2% 15 34.1% 3 6.8% 44 Crack stitching 1432.6% 9 20.9% 11 25.6% 7 16.3% 2 4.7% 0 0.0% 43 Longitudinal edge drains 920.9% 8 18.6% 11 25.6% 11 25.6% 3 7.0% 2 4.7% 43 Lane replacement 1125.6% 9 20.9% 6 14.0% 12 27.9% 2 4.7% 3 7.0% 43 Table 9. Types of concrete pavement rehabilitation/restoration techniques used by agencies.
32 Construction and Rehabilitation of Concrete Pavements Under Traffic v the same time as the lane closure operation [23% (9 out of 39 agencies)], and crossroad closures only in the paving area and limiting the number of paved crossroad closures in the work zone area [23% (9 out of 39 agencies)]. The least-used MOT activities were pilot car on a 24/7 basis [13% (5 out of 39 agencies)] and split barricades some distance away from the project to alert heavy equipment operators of road closures [8% (3 out of 39 agencies)]. Note that it is quite likely that some of these MOT activities are used for the construction of asphalt pavements, particularly under traffic, but are not commonly practiced by agencies for the construction of concrete pavements. Several agencies have incorporated a number of FHWA Every Day Counts (EDC) tools and technologies into work zone management, including the Traffic Incident Management (TIM) Responder Training program and Smarter Work Zones initiative. Twenty-eight percent (11 out of 39 agencies) use TIM training. The TIM training program focuses on a response effort that protects motorists and responders while minimizing the impact on traffic flow. TIM efforts include detecting, verifying, and responding to incidents; clearing the incident scene; and restoring traffic flow. Based on the severity or type of incident, first responders may represent law enforcement, fire, transportation, emergency medical services, public safety, towing and recovery, public works, and hazardous materials disciplines. Thirty-three percent (13 out of 39 agencies) use Smarter Work Zones, which includes two strategies for managing work zones and work zone traffic to minimize travel delays and help Figure 3. MOT planning and implementation practices adopted by agencies.
Agency Perspectives and Practices for Constructing or Rehabilitating Concrete Pavements Under Traffic 33 maintain motorist and worker safety. These two strategies are (1) project coordination, which involves coordination within a single project or among multiple projects within a corridor, network, or region, and possibly across agency jurisdictions, to minimize work zone impacts and produce time and cost savings, and (2) technology applications such as queue management and speed management that involve deployment of ITSs for dynamic management of work zone traffic impacts to improve motorist and worker safety and mitigate work zoneârelated congestion. Summaries of additional responses related to agency-specific MOT planning and implemen- tation practices are as follows: â¢ Georgia allows contractors to work on either side of the road on a case-by-case basis by add- ing special provisions to the contract. â¢ The Illinois Tollway protects high-speed Interstate work zones with temporary barrier walls in most cases. The Illinois Tollway never allows split traffic MOT. In the future, the Illinois Tollway will maintain the same number of lanes during construction peak hours as before the construction project; the use of counterflow MOT will be necessary at times to achieve this objective. â¢ Florida permits pilot car use, but it is not often the MOT choice of contractors. â¢ In South Carolina, concrete construction and rehabilitation (other than composite pave- ments) is almost always performed on the Interstate system, where patching operations are usually performed under nightly lane closures. New construction is most commonly done along with widening and may employ different considerations for MOT. â¢ Nebraska allows multiple work zones for the various construction activities, but not specifi- cally for each activity or as noted on the plans. It allows single-lane closures (on multilane systems), with no open holes after, to be performed during nighttime conditions. During the day, single-lane closures on two-lane, two-way roads and high-volume, multilane systems are allowed. Nebraska would likely allow 24/7 pilot car use on request for certain situations and would also allow the closing of crossroads in the paving area, but requires an alternate paved route for the crossroad. â¢ Utah prepares a preliminary layout of MOT during the preliminary design phase. â¢ Traffic crossovers will be considered by Connecticut in the future. Materials and Design The materials and design used on a project affect project schedule, time for construction, and number of construction/haul vehicles, all of which can have an impact on traffic. A summary of the material and design practices used by agencies is shown in Figure 4. Ninety-three percent (37 out of 40 agencies) of survey respondents used HES concrete for patching. Fifty-three percent (21 out of 40 agencies) used chemical or mechanical subgrade soil stabilization techniques before subbase placement, and the same percentage modified the base and subbase. Fifty percent (20 out of 40 agencies) of the survey respondents reused existing sub- base aggregates in new pavement designs, 45% (18 out of 40 agencies) used reclaimed asphalt pavement (RAP), and 45% used precast concrete technologies. Forty-three percent (17 out of 40 agencies) used recycled concrete aggregate (RCA), and 43% used nonwoven geotextiles as interlayers in concrete pavement systems. Summaries of additional responses related to agency-specific materials and design practices are as follows: â¢ Ohio allows RCA in concrete mixes, but it is rarely used. Ohio also performs global chemical stabilization on all of its rebuild projects.
34 Construction and Rehabilitation of Concrete Pavements Under Traffic â¢ North Dakota specifications allow for use of HES concrete; however, North Dakota reported that it had experienced durability issues with HES that have led to its reduced use in recent years. â¢ Nebraska noted that it uses RCA and RAP as a base course material. Nebraska also used pre- cast pavement in a limited way on a recent research project. â¢ Washington State and the District of Columbia sometimes use HES concrete. â¢ New Jersey has used a synthetic resin compound for partial-depth repairs and polyurethane grout for slab stabilization. New Jersey also reported that it has not reconstructed pavement or constructed new pavement recently, and it is currently rehabilitating existing concrete using precast panels. The precast repairs are both continuous (to rehabilitate continuous failed slabs) and intermittent. â¢ North Carolina, Arizona, and Connecticut also indicated that they would like to use HES concrete in the future. California intends to reach a higher strength of concrete much faster on future projects. â¢ Wyoming would consider allowing recycling in the future. A similar sentiment was echoed by Tennessee, which would like to use recycled materials such as recycled concrete. â¢ Utah suggested a willingness to change materials but not where it would sacrifice quality or performance. Massachusetts would consider not using local contractor mixtures. Nebraska requires a maturity method to be used for opening strength, in addition to approved mix designs with early strength capabilities. â¢ Ohio plans to use hollow dowel bars, durable rapid-setting patch materials, and precast panels in the future. South Carolina would consider constructing precast pavements. â¢ The Illinois Tollway uses concrete mix designs based on performance, with minimal delay to opening pavement to construction traffic. Specified minimum compressive strengths for opening new or rehabilitated roads to construction traffic have been reduced from 3,200 psi to 2,500 psi with no issues; strengths may be lowered further to expedite opening to construction traffic. The Illinois Tollway considers only the most durable fast-setting patching materials for maintenance. Figure 4. Summary of material and design practices used by respondent agencies.
Agency Perspectives and Practices for Constructing or Rehabilitating Concrete Pavements Under Traffic 35 Paving Equipment and Concrete Placement In recent years, there have been many improvements in paving equipment and concrete place- ment techniques that help with various aspects of construction and rehabilitation of concrete pavements under traffic, including accelerating construction, reducing clearance requirements, and allowing earlier opening to traffic. A summary of the materials and design practices used by highway agencies is shown in Figure 5. Seventy-three percent (24 out of 33 agencies) of respondents used stringless paving technol- ogy. The same number of respondents used early-age saw-cutting. Sixty-four percent (21 out of 33 agencies) used maturity recording devices/sensors, while 55% (18 out of 33) used 3D modeling technology. Less commonly used technologies were RCC (40%, or 13 out of 33 agencies) and zero-clearance pavers (30%, or 10 out of 33 agencies). Summaries of additional responses related to agency-specific paving equipment and place- ment techniques are as follows: â¢ Ohio specifications allow use of listed paving equipment/placement techniques; however, the contractors typically do not choose to use them. Ohio has only used RCC for temporary pavement. It has infrequently used maturity meters for rapid repair patching. â¢ California indicated that RCC paving is still a new technique in that state. Nebraska has been considering use of RCC. â¢ Indiana intends to use RCC in the future. â¢ Missouriâs biggest construction consideration is the use of edge drop-offs during construc- tion. Designers have to determine if there is adequate room for temporary edge treatments or if a temporary barrier will be required. â¢ Arkansas intends to use maturity sensors, 3D modeling, stringless paving, zero-clearance pavers, and real-time smoothness equipment in the future. â¢ North Dakota would like to use stringless paving. â¢ The Illinois Tollway currently allows conventional or stringless pavers with or without dowel bar inserters for concrete paving. Figure 5. Paving equipment and concrete placement techniques used by agencies.
36 Construction and Rehabilitation of Concrete Pavements Under Traffic Paving Operations As in the case of paving equipment, paving operations can also affect the extent and duration of traffic impacts. Decisions on closures, detours, two-lane versus one-lane paving, and haul roads all play a key role in how quickly a project can be completed and in MOT plans. A sum- mary of the paving operation practices used by highway agencies is shown in Figure 6. A majority of the survey respondents (72%, or 23 out of 32 agencies) considered paving plan development by the contractor for agency approval. Sixty-three percent (20 out of 32 agen- cies) reported that they were likely to consider time and access requirements to identify the project paving goals. Sixty-three percent would consider two-lane versus one-lane paving scenarios. Fifty percent (16 out of 32 agencies) considered haul-road needs based on limita- tions placed on contractor paving plans. Forty-four percent (14 out of 32 agencies) required completion of lane paving, shoulder construction, and pavement marking processes before allowing paving of the adjacent lane or moving traffic control forward. Thirty-four percent (11 out of 32 agencies) of the respondents evaluated paving plans based on the contractorâs ability to deliver pavement, shoulders, and markings in a continuous and timely manner. The least-used (9%, or 3 out of 32 agencies) paving operation practice was to allow for additional haul-road designations and local compensation to provide for raw material and concrete delivery. Summaries of additional responses related to agency-specific paving equipment and place- ment techniques are as follows: â¢ The Illinois Tollwayâs paving operations are as controlled by standard specifications. â¢ Minnesota specifies which lanes can be closed, how many lanes can be closed, and duration of lane closures in the contract. Contractors will then develop a paving/rehabilitation plan to fit contract closure requirements. â¢ Utah defines limits for development of the paving plan by the contractor, which is later reviewed by the agency. Figure 6. Summary of paving operations performed by respondent agencies.
Agency Perspectives and Practices for Constructing or Rehabilitating Concrete Pavements Under Traffic 37 Project Management Proper management of a construction project is necessary to ensure that the project is pro- ceeding as planned and is completed on time and within budget while meeting agency needs for quality, safety, and traffic impacts. A summary of the project management practices used by the survey respondents is presented in Figure 7. A majority of survey respondents (82%, or 32 out of 39 agencies) noted that they used general engineering consultants to help with project delivery. Seventy-two percent (28 out of 39 agen- cies) used in-house project management training programs, and 51% (20 out of 39 agencies) used project management manuals or other documentation on agency best practices. A suite of project management tools/web services, geographic information systems (GISs) and data management tools, and e-Construction practices were used by 26% (10 out of 39 agencies), 33% (13 out of 39 agencies), and 46% (18 out of 39 agencies), respectively. The e-Construction program is a paperless construction administration delivery process that includes electronic submission of all construction documentation by all stakeholders, electronic document routing/ approvals (e-signature), and digital management of all construction documentation in a secure environment allowing distribution to all project stakeholders through mobile devices. The least-used project management technique among the survey respondents was risk management tools/systems (23%, or 9 out of 39 agencies). In addition, Nebraska recently started using e-Construction practices, and the Illinois Tollway uses the e-Builder program instead of the e-Construction program. Project Delivery The mechanism of project delivery is another factor that has a bearing on construction proj- ects in terms of how they are managed and executed, and it has a direct impact on the speed of decision-making processes and the schedule for project completion, which in turn can have an impact on the extent to which traffic is affected. A summary of the project delivery methods used by respondent agencies is shown in Figure 8. Figure 7. Summary of project management practices used by agencies.
38 Construction and Rehabilitation of Concrete Pavements Under Traffic A majority of survey respondents (84%, 32 out of 38 agencies) used a conventional DBB project delivery method. Fifty-five percent (21 out of 38 agencies) used a DB project delivery method, where the design and construction duties are performed by the same contractor. Eighteen per- cent (7 out of 38 agencies) used DB variations such as DBM, which combines maintenance provisions with DB, and DBW, which combines warranty provisions with DB. Less-used project delivery methods included construction manager/general contractor (CM/GC) (18%, or 7 out of 38 agencies), PPP (13%, or 5 out of 38 agencies), and indefinite delivery/indefinite quantity (ID/IQ) (8%, or 3 out of 38 agencies). In CM/GC, also known as construction manager at risk, the agency hires a contractor to provide feedback during the first contract phase, the design phase. Once the design phase is complete, the agency and contractor negotiate on the price for the construction contract. If all parties are in agreement regarding costs, then the second contract phase, the construction phase, is started, and construction begins. PPP is a process where a private entity designs, builds, and maintains a section of roadway in return for a toll or fee. ID/IQ contracting is a type of contract that provides for an indefinite quantity of supplies or services during a fixed period of time. Summaries of additional responses regarding agency-specific project delivery practices are as follows: â¢ Ohio has performed many of the delivery methods listed as pilots, but answers to the ques- tionnaire reflect normal practice. Ohio also typically would choose the delivery method first, and the pavement type would not be a factor in that decision. â¢ Delaware uses some of the project delivery methods listed, but not for concrete rehabilitation. â¢ Nebraska and Indiana plan to use CM/GC. Nebraska and California plan to use more DB in the future. â¢ Oklahoma uses traditional DBB, while most of Utahâs big projects are DB or CM/GC. â¢ Arkansas recently used PPP for the first time; however, it plans to use DB, alternate technical concepts (ATCs), and CM/GC in the future. â¢ New Jersey awards projects to an eligible lower bidder. â¢ Minnesota has a 30-day warranty on concrete pavement repairs. Project Procurement The contracting and procurement phase is important in expediting construction and achiev- ing quality. Procurement practices can be tailored to balance agency goals for costs, project dura- tion, quality, traffic impacts, and other factors. A summary of the project procurement practices used by respondent agencies is shown in Figure 9. Figure 8. Project delivery methods used by agencies.
Agency Perspectives and Practices for Constructing or Rehabilitating Concrete Pavements Under Traffic 39 Seventy-six percent (29 out of 38 agencies) of the respondents used VE, a systematic process of review and analysis of a project (during the concept and design phases) by a multidiscipline team. Seventy-four percent (28 out of 38 agencies) performed constructability reviews to evalu- ate all aspects of the construction project, including shortening construction time and reducing delays. Sixty-eight percent (26 out of 38 agencies) indicated that they used some form of perfor- mance specifications. Cost-plus-time bidding (A+B), a procedure that incorporates the lowest initial cost but also factors into the selection process the time to complete the project, was used by 61% (23 out of 38 agencies) of the respondents. Partnering, a formal process in which all parties to a project voluntarily agree to adopt a cooperative and team-based approach to project development and problem resolution, was used by 50% (19 out of 38 agencies) of the respondents. Thirty-two percent (12 out of 38 agencies) used alternate bids (bids that state an amount that may be added to or subtracted from the quoted price if alternate methods and materials are chosen), 26% (10 out of 38 agencies) used requests for proposal (RFPs), and 24% (9 out of 38 agencies) used ATCs, where a bidder proposes changes to an agencyâs base design configurations to provide a solution that is equal to or better than the requirements of the base design. Lesser-used procurement practices were multiparameter bidding (A+B+quality), additive alternates/tied bids (bids that state an amount that must be added to the quoted price if a speci- fied change in the scope of work is accepted by the agency), reverse auction bidding (type of auction in which several sellers offer their items for bidding and compete for the price that the agency will accept; the agency has the option to accept any bid or reject all), and alternate design (two or more designs are presented for the same project in the bid documents). Summaries of additional responses regarding agency-specific project procurement practices are as follows: â¢ Although North Dakota has used formal partnering in the past, it has been at least 10 years since formal partnering was used on a concrete project. â¢ New Jersey uses an advertised bid package for bidding by qualified contractors and awards the project to the lowest qualified bidder. Figure 9. Project procurement practices used by agencies.
40 Construction and Rehabilitation of Concrete Pavements Under Traffic â¢ Utahâs procurement type is based on what will provide best value (e.g., complicated projects work best under DB or CM/GC, contractor can be involved in MOT). Utah uses price + time bidding on almost all contracts. The stateâs agency looks at lane requirements and all options that are feasible for constructing with those requirements. It provides information to the contractor on the number of lanes required at each hour of the day to define acceptable work windows and to limit impact on urban roadways. Lane splits for multiple-lane construction are allowed. â¢ Wyoming conducts VE studies during the preliminary design phase. â¢ Ohio considers VE, partnering, and contractor-designed MOT. â¢ In California, the resident engineer and contractor may agree to modify the plans to expedite construction. Payment Methods Various forms of I/D are effective tools that can be used by an agency to accelerate construc- tion and reduce delays and corresponding traffic impacts. A summary of the payment methods used by respondent agencies is shown in Figure 10. Eighty-eight percent (35 out of 40 agencies) of the survey respondents used liquidated dam- ages (a specified monetary amount per unit time) for late completion of new construction or for late opening to traffic after nighttime rehabilitation, while 75% (30 out of 40 agencies) used I/D provisions for early/late completion of the project. Forty percent (16 out of 40 agencies) and 28% (11 out of 40 agencies) of respondents indi- cated that they used lane rentals (a rental fee to contractors for closing lanes and shoulders to do construction work based on the estimated cost of delay or inconvenience to the road user) and warranties, respectively, for project-related payments. Additionally, respondents also noted that they used payment options such as lump sum (23%, or 9 out of 40 agencies) and flexible notice-to-proceed dates (20%, or 8 out of 40 agencies). The least-used payment methods were active management payment mechanisms (AMPMs) (incentives based on the measured travel speed and measured volumes in comparison to theoretical Figure 10. Summary of payment methods used by respondent agencies.
Agency Perspectives and Practices for Constructing or Rehabilitating Concrete Pavements Under Traffic 41 percentages of roadway capacity), liquidated savings (rewarding the contractor for each calendar day the contract is completed and accepted prior to the expiration of allowable contract time), and no-excuse incentives (an incentive for reaching a project milestone without allowing a con- tractor to receive a time extension and receive the incentive). Summaries of additional responses regarding agency-specific payment method practices are as follows: â¢ The Illinois Tollway uses I/D provisions based on final performance measurements. â¢ Ohioâs choice to use these methods is typically based on other factors and policies, and the pavement type is not a factor in selecting the method. â¢ Nebraska uses conventional progress estimates based on accepted quantities per item at the itemâs bid prices. Nebraska noted that it is just starting to use lane rental and has used I/D for some projects. The agency intends to consider greater use of I/D for completion time. â¢ Minnesota has a 30-day warranty. The 30-day warranty starts when all repairs are completed in a single lane, including diamond grinding. Project-Related Communications Project-related communications within an agency and between various stakeholders are crucial for smooth and timely execution of construction and rehabilitation of concrete pave- ments under traffic. With an understanding that the degree and extent of communications can vary depending on the scope and extent of a project, survey respondents were asked about the project-related communications used at their agencies (Figure 11). From the 40 responses received, all agencies noted that they conducted preconstruction con- ferences between the agency, contractor, local community representatives, law enforcement, and others. Ninety percent (36 out of 40 agencies) conducted periodic construction team meetings, 88% (35 out of 40 agencies) conducted prepaving team meetings, and 85% (34 out of 40 agencies) Figure 11. Project-related communication practices adopted by agencies.
42 Construction and Rehabilitation of Concrete Pavements Under Traffic conducted meetings within the highway agency design and construction staff during design and prior to construction. Project coordination meetings were less frequently used by highway agencies. Seventy- three percent (29 out of 40 agencies) held project coordination meetings on right-of-way (ROW) and utilities; 68% (27 out of 40 agencies) held project coordination meetings with the media, schools, businesses, and emergency services; 65% (26 out of 40 agencies) held project coordination meetings with other transportation infrastructure agencies; and 60% (24 out of 40 agencies) held project coordination meetings with representatives of other projects in the vicinity. Forty-five percent (18 out of 40 agencies) held public meetings after the preconstruc- tion conference but before beginning construction work. The least-used option was setting up community task forces (13%, or 5 out of 40 agencies). The lower frequency of project coordination meetings may be a reflection of the nature of concrete pavement construction in some states rather than a policy decision. Agencies with a small amount of concrete pavement construction and rehabilitation may not have many projects with wide impacts that require project coordination. Summaries of additional responses related to agency-specific, project-related communica- tions are as follows: â¢ To obtain the public buy-in prior to proceeding with the project, Georgia conducts public meetings in the design phase and prior to the preconstruction conference. â¢ The Illinois Tollway uses its website and construction information signs for project-related communications. â¢ On a recently completed project, New Jersey coordinated with the New Jersey State Thruway Authority on lane closings to reduce traffic disruptions. Public Outreach An important aspect of construction and rehabilitation of concrete pavements under traf- fic is to communicate project impacts to the traveling public, local residents and businesses, and other affected parties and agencies. A well-planned and well-executed public outreach program can be an effective tool to help reduce the extent and severity of traffic impacts. Questionnaire responses related to public outreach practiced by highway agencies are sum- marized in Figure 12. A significant majority of survey respondents (95%, or 38 out of 40 agencies) used press releases or media alerts. The second most commonly used practice was social media (Facebook, Twitter, LinkedIn, etc.), chosen by 83% (33 out of 40 agencies) of the respondents. Seventy-five percent (30 out of 40 agencies) used a dedicated project website for public outreach. Less common approaches to public outreach were brochures and mailers (35%, or 14 out of 40 agencies), newsletters and paid advertisements (38%, or 15 out of 40 agencies), public information centers (43%, or 17 out of 40 agencies), telephone hotlines (48%, or 19 out of 40 agencies), planned lane closure websites (43%, or 17 out of 40 agencies), public service announcements (43%), toll-free telephone numbers/hotlines (43%), and traveler information systems (53%, or 21 out of 40 agencies). Forty percent (16 out of 40) of agencies developed visual content for websites and meetings. The least preferred public outreach practices were the use of press kits and business survival kits (containing tips/tactics for success during work zone con- struction, business survival videos, and general project information), public satisfaction surveys (formal/informal), and rideshare promotions, with responses of 18% (7 out of 40 agencies), 15% (6 out of 40 agencies), and 10% (4 out of 40 agencies), respectively.
Agency Perspectives and Practices for Constructing or Rehabilitating Concrete Pavements Under Traffic 43 Summaries of additional responses regarding agency-specific public outreach practices are as follows: â¢ The Illinois Tollway uses emails to I-Pass patrons who may be affected by a construction project. â¢ Nebraska uses portable and permanent variable message boards to notify travelers of upcom- ing work. â¢ Massachusetts uses a web platform for information on all construction work zones, lane clo- sures, and construction. â¢ Utah provides regular project updates using an email list. â¢ New Jersey provides preconstruction notices to local officials and other transportation agencies. Motorist Information As in the case of public outreach, conveying timely information to motorists is critical for reducing traffic impacts while constructing and rehabilitating concrete pavements under traffic. Agency responses to survey questions related to communications with motorists are shown in Figure 13. Ninety-five percent of the survey respondents (38 out of 40 agencies) used changeable mes- sage signs, and 78% of the survey respondents (31 out of 40 agencies) used social media to communicate up-to-date traffic information to the traveling public. Figure 12. Public outreach practices used by agencies.
44 Construction and Rehabilitation of Concrete Pavements Under Traffic Less common practices, such as 511 traveler information systems, highway information networks/websites, and temporary motorist information signs, were used by 65% (26 out of 40 agencies), 50% (20 out of 40 agencies), and 63% (25 out of 40 agencies) of respondents, respectively. Forty-eight percent (19 out of 40 agencies) used transportation management centers to disseminate information to the traveling public. Traffic radio stations and highway advisory radio systems were used by 43% (17 out of 40 agencies) and 33% (13 out of 40 agen- cies), respectively. The least preferred option was freight travel information systems (3 out of 40 agencies, or 8%). In addition, Florida uses a community-based traffic and navigation application known as Waze for motorist information purposes. Modification of Standard Practices for Constructing or Rehabilitating Concrete Pavements Under Traffic The survey respondents identified reasons for modifying their agenciesâ standard practices for constructing or rehabilitating concrete pavements under traffic conditions and ranked them on a scale ranging from âleast importantâ to âmost important.â More than 90% of the survey respondents considered expedited construction operations, reduced traffic delays, maintenance of safe traffic operations, and protection against premature concrete pavement failures as impor- tant or most important factors in modifying agency practices. The survey respondents were largely neutral in their outlook on perceived risk-sharing or risk-transfer benefit (48%, or 17 out of 35 agencies) and potential for greater contractor innovation (46%, or 16 out of 35 agencies). Motivational factors that were considered somewhat important or least important included legislative/statutory requirement (for 38%, or 13 out of 34 agencies) and positive experience of other agencies (31%, or 11 out of 35 agencies). The responses are summarized in Table 10. The survey respondents were asked about their reservations and concerns about modifying their agenciesâ standard practices to consider constructing or rehabilitating concrete pavements Figure 13. Motorist information practices used by agencies.
Agency Perspectives and Practices for Constructing or Rehabilitating Concrete Pavements Under Traffic 45 Reason Number (percentage) of Agencies Noting Reason for Modifying Standard Practice Responses Most Important Important Neutral Somewhat Important Least Important Legislative/statutory requirement 3 8.8% 9 26.5% 9 26.5% 6 17.6% 7 20.6% 34 Expedited construction operations 10 27.0% 25 67.6% 2 5.4% 0 0.0% 0 0.0% 37 Reduced traffic delays 1847.4% 19 50.0% 0 0.0% 0 0.0% 1 2.6% 38 Maintenance of safe traffic operations 23 60.5% 13 34.2% 1 2.6% 0 0.0% 1 2.6% 38 Increased road-user satisfaction 8 22.2% 23 63.9% 4 11.1% 0 0.0% 1 2.8% 36 Perceived risk-sharing or risk- transfer benefit 2 5.7% 7 20.0% 17 48.6% 7 20.0% 2 5.7% 35 Perceived maintenance cost- saving benefit 6 16.7% 23 63.9% 4 11.1% 2 5.6% 1 2.8% 36 Perceived construction cost- saving benefit 6 17.6% 21 61.8% 3 8.8% 3 8.8% 1 2.9% 34 Perceived life-cycle cost- saving benefit 8 21.6% 23 62.2% 3 8.1% 1 2.7% 2 5.4% 37 Perceived performance- improvement benefit 6 17.1% 22 62.9% 5 14.3% 1 2.9% 1 2.9% 35 Potential for greater contractor innovation 2 5.7% 15 42.9% 16 45.7% 1 2.9% 1 2.9% 35 Protection against premature concrete pavement failures 9 25.7% 23 65.7% 2 5.7% 1 2.9% 1 2.9% 35 Agency policy, bidding, outsourcing, or procurement guidelines encourage use of innovative practices 1 2.9% 16 45.7% 13 37.1% 3 8.6% 2 5.7% 35 Positive experience of other agencies 1 2.9% 10 28.6% 13 37.1% 7 20.0% 4 11.4% 35 Table 10. Reasons for modifying agencyâs standard practices for constructing or rehabilitating concrete pavements under traffic. under traffic conditions, and were asked to rank these reservations on a scale from âleast impor- tantâ to âmost important.â Sixty-four percent (23 out of 36 agencies) of the survey respon- dents considered potentially higher bid prices as an important factor. More than 40% of the respondents chose local construction contractor resistance, absence of established performance criteria/standards, perceived negative impact on competition (i.e., reduced number of bidders, particularly among small contractors), and possible increase in disputes with contractors and litigation as important or most important factors. Prohibition or discouragement by state law (45% of respondents), prohibition or discouragement by agency administrative policy or bidding and procurement guidelines (47% of respondents), and administrative burden (41% of survey respondents) were considered somewhat or least important factors. The responses are summa- rized in Table 11.
46 Construction and Rehabilitation of Concrete Pavements Under Traffic Reservations/Concerns Number (percentage) of Agencies Noting Reservation/Concern for Modifying Standard Practice Responses Most Important Important Neutral Somewhat Important Least Important Prohibited or discouraged by state law 2 6.1% 4 12.1% 12 36.4% 1 3.0% 14 42.4% Prohibited or discouraged by agency administrative policy or bidding and procurement guidelines 2 5.9% 8 23.5% 8 23.5% 5 14.7% 11 32.4% Potentially higher bid prices 00.0% 23 63.9% 4 11.1% 6 16.7% 3 8.3% Local construction contractor resistance 3 8.6% 14 40.0% 7 20.0% 7 20.0% 4 11.4% Possible increase in change orders/work orders 0 0.0% 11 33.3% 14 42.4% 5 15.2% 3 9.1% Risk-sharing/risk-transfer concerns 0 0.0% 12 35.3% 17 50.0% 2 5.9% 3 8.8% Absence of established performance criteria/standards 3 8.6% 12 34.3% 12 34.3% 5 14.3% 3 8.6% Perceived negative impact on competition (i.e., reduced number of bidders, particularly among small contractors) 3 8.3% 11 30.6% 13 36.1% 7 19.4% 2 5.6% Negative experience of other agencies 2 5.9% 7 20.6% 16 47.1% 6 17.6% 3 8.8% Possible increase in disputes with contractors and litigation 1 2.9% 15 42.9% 12 34.3% 4 11.4% 4 11.4% Too burdensome administratively 2 5.9% 7 20.6% 11 32.4% 5 14.7% 9 26.5% 33 34 36 35 33 34 35 36 34 35 34 Table 11. Reasons for not modifying standard practices to consider construction or rehabilitation of concrete pavements under traffic.