Concrete Technology for Transportation Applications (2019)

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92 Introduction A survey was prepared and sent electronically using online survey software to all members of the ASSHTO Committee on Materials and Pavements (COMP) representing the 50 state highway agencies and the District of Columbia. The survey was a questionnaire composed of 24 questions about DOT practices related to implementation of concrete technologies in transportation projects, possible shortages in quality aggregates and fly ash, use of recyclable materials, and barriers to concrete technology implementation. The survey questions were divided into eight main topic areas including: 1. General Information. 2. Concrete Technology Implementation. 3. Other Concrete Technologies (not covered in the synthesis). 4. Depletion of Quality Aggregates. 5. Availability of Fly Ash. 6. Use of Recycled and Reclaimed Materials. 7. Barriers to Technology Implementation. 8. Case Examples. The questionnaire is shown in Appendix A. Forty state DOTs responded to the questionnaire. These states included Alabama, Arizona, Arkansas, Colorado, Connecticut, Delaware, Florida, Georgia, Idaho, Illinois, Kansas, Kentucky, Louisiana, Maine, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, New Hampshire, New Jersey, New York, North Carolina, North Dakota, Ohio, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Washington, West Virginia, Wisconsin, and Wyoming. Their detailed responses are shown in Appendix B. This chapter summarizes the state responses to the survey questions. Responses to Survey Questionnaire General Information In this section the name and contact information of the state DOT respondent was provided. The names of respondents are not included in Appendix B. In response to the questions whether the respondent was a COMP member, 17 responded “Yes” and 23 responded “No.” Because of the broad nature of the questions, which covered many technologies, both established and new, the responses may have been composed by the COMP state member or designee with assistance from other agency professionals. C H A P T E R 3 Survey of State Practices

Survey of State Practices 93 Concrete Technologies This topic included seven questions concerning 14 concrete technologies, including those that were the main focus of the synthesis, and others that were not but were still considered important technologies. The surveyed technologies were SCC, UHSC, HESC, PC, RCC, UHPC, ICC, TCMC, lightweight concrete (LC), lightweight cellular/foamed concrete (LCC), PCP, VHESC or rapid-hardening concrete, latex-modified concrete (LMC), and polymer concrete (Poly C). The questions were seeking information on implementation status, availability of specifications, number of projects and average project age, application types (pavements and/or structures), and implementation challenges. Responses to Technology Use and Specifications Availability The responses from the 40 states on technology use and availability of specifications for the technologies are shown in Table 9. HSC seems to be used in all 40 responding states. This was inferred based on the survey results of technology use including HSC, UHSC, SCC, ICC, UHPC, and HESC. The top three most implemented technologies according to the survey are SCC (38 states), HESC (37 states), and LMC (31 states). The least implemented technologies are UHSC (15 states), PC (14 states), and ICC (9 states). With respect to the availability of specifications for the implemented technologies, the top three technologies are SCC (34 states), HESC (31 states), and LMC (25 states). The lowest three technologies are UHSC (9 states), PC (8 states), and ICC (7 states). Technology Applications The states reported a variety of applications for the 14 technologies in both pavements and structures. High early strength technologies such as HESC, VHESC, LMC, and Poly C are mainly used for rapid or emergency repairs of pavements and bridges and for overlays. Other technologies such as SCC, UHSC, UHPC, and ICC are used in cast-in-place or in pre- cast structural applications, while PCP, RCC, and PC are used in pavement construction and overlays. The TCMC technology is used to control heat generation in mass elements of bridges, LC is used as a lightweight filler in movable bridge decks and in overlays. LCC is used for filling trenches, geotechnical voids, and gaps and as a backfill material for retaining walls. Project Information The number of states that have constructed projects using concrete technologies is shown in Table 10. Each state respondent indicted, based on their estimate, the number of projects where the specific technology was used. HESC and SCC seem to be well established in many states. For example, 29 states indicated that they have constructed between 11 and more than 25 HESC projects, and 27 states indicated having between 11 and more than 25 SCC projects. The UHPC seems to have gained more acceptance, as evident by the number of states (20) that have implemented the technology (1 to 10 projects). A similar trend can be observed in the use of LC (16 states), RCC (15 states), and PCP (14 states). These fairly young technologies (except LC) are gaining more acceptance in transportation projects as a result of more appli- cations, experience, training, and availability of construction guidelines. The age of the projects is also an indication of the maturity in knowledge and use of technol- ogy as well as demonstrated performance in various applications. Table 11 shows the range of service lives (to present day) of the projects as estimated by the respondents. The projects with technologies that have been in service from 6 to more than 10 years are SCC (in 29 states),

94 Concrete Technology for Transportation Applications Pervious concrete (PC) 14 DE, FL, IL, KY, ME, MN, NH, NY, OR, PA, RI, VT, WA, WY 8 DE, MN, NH, NY, PA, VT, WA, WY Recycled concrete aggregate (RCA) 16 AL, AR, CO, CT, FL, IL, MI, MN, MO, NH, NY, OH, TX, WA, WV, WY 12 AL, CO, CT, FL, IL, MI, MN, NY, TX, WA, WV, WY High early strength concrete (HESC) 37 AL, AZ, AR, CO, CT, DE, FL, GA, ID, IL, KS, KY, LA, MA, MI, MN, MS, MO, NE, NH, NJ, NY, NC, OH, OR, PA, RI, SC, SD, TN, TX, UT, VT, WA, WV, WI, WY 31 AL, AZ, AR, CO, CT, DE, FL, GA, IL, KS, KY, LA, MA, MI, MO, NE, NH, NJ, NY, NC, OH, OR, PA, SD, TN, TX, UT, VT, WA, WV, WI, WY Very high early strength concrete (VHESC) ( rapid-hardening concrete) 24 AL, CO, CT, DE, FL, IL, KY, LA, ME, MA, MI, MN, MO, NH, NY, NC, OH, RI, SD, TX, UT, WA, WI, WY 16 CT, FL, IL, KY, ME, MA, MI, MN, NH, NY, OH, RI, TX, UT, WA, WY Lightweight concrete (LC) 29 CT, DE, FL, IL, KS, KY, ME, MA, MI, MN, MO, NE, NH, NJ, NY, NC, OH, OR, PA, RI, SC, SD, TN, TX, UT, VT, WA, WV, WI 22 CT, DE, FL, KY, ME, MI, MN, MO, NE, NH, NJ, NY, NC, OH, PA, RI, TN, TX, UT, VT, WV, WI Lightweight cellular/ foamed concrete (LCC) 24 AZ, CO, CT, DE, FL, ID, IL, KY, ME, MA, MI, MN, NH, NY, NC, OH, OR, RI, SD, UT, VT, WA, WI, WY 14 DE, FL, ID, IL, KY, ME, MI, MN, NH, NY, OH, SD, WA, WY Latex-modified concrete (LMC) 31 AR, CO, CT, DE, FL, IL, KS, KY, LA, ME, MA, MI, MN, MO, MT, NE, NJ, NY, NC, OH, OR, PA, RI, SC, SD, TN, TX, UT, WA, WV, WY 25 AR, CO, CT, DE, FL, IL, KY, LA, ME, MI, MO, NJ, NY, NC, OH, OR, PA, RI, SC, TN, TX, UT, WA, WV, WY Polymer concrete (Poly C) 20 AL, AZ, CO, CT, DE, FL, IL, KS, KY, MA, MN, NE, NJ, NY, NC, OR, PA, TX, WA, WI 14 AL, AZ, CO, DE, FL, IL, KS, NJ, NY, OR, PA, TX, WA, WI Technology Technology Users Availability of No. of States State DOT No. of States Specifications/Guidelines State DOT High-strength concrete (HSC) (Not surveyed but inferred from responses to other technologies) 40 AL, AZ, AR, CO, CT, DE, FL, GA, ID, IL, KS, KY, LA, ME, MA, MI, MN, MS, MO, MT, NE, NH, NJ, NY, NC, ND, OH, OR, PA, RI, SC, SD, TN, TX, UT, VT, WA, WV, WI, WY 40 AL, AZ, AR, CO, CT, DE, FL, GA, ID, IL, KS, KY, LA, ME, MA, MI, MN, MS, MO, MT, NE, NH, NJ, NY, NC, ND, OH, OR, PA, RI, SC, SD, TN, TX, UT, VT, WA, WV, WI, WY Ultrahigh-strength concrete (UHSC) >10,000 psi 15 CT, DE, GA, KY, ME, MI, MO, NE, NJ, NY, OR, PA, RI, TX, VT 9 DE, GA, MI, MO, NE, NJ, NY, PA, RI Self-consolidating concrete (SCC) 38 AL, AZ, CO, CT, DE, FL, GA, ID, IL, KS, KY, LA, ME, MA, MI, MN, MS, MO, MT, NE, NH, NJ, NY, NC, OH, OR, PA, RI, SC, SD, TN, TX, UT, VT, WA, WV, WI, WY 34 AL, AZ, CO, DE, FL, GA, ID, IL, KS, KY, LA, ME, MA, MN, MS, MO, MT, NE, NH, NJ, NY, NC, OH, PA, RI, SC, SD, TN, TX, UT, VT, WA, WV, WI, WY Internally cured concrete (ICC) 9 IL, KS, LA, MN, NY, NC, OH, UT, WV 7 IL, LA, MN, NY, OH, UT, WV Ultrahigh- performance concrete (UHPC) 22 AL, CT, DE, FL, GA, ID, IL, ME, MA, MI, MT, NE, NJ, NY, OH, OR, PA, RI, UT, VT, WI, WY 19 AL, CT, DE, GA, ID, IL, ME, MA, MI, MT, NE, NJ, NY, OH, OR, PA, RI, UT, VT, WI, WY Temperature control of mass concrete (TCMC) 30 AR, CO, CT, DE, FL, GA, IL, KS, KY, LA, ME, MA, MI, MN, MT, NJ, NY, ND, OH, PA, RI, SC, SD, TN, TX, VT, WA, WV, WI, WY 23 CO, CT, DE, FL, GA, IL, KY, LA, MA, MI, MN, NJ, NY, ND, OH, PA, RI, SC, TX, VT, WA, WV, WY Precast concrete pavement (PCP) 21 AL, CO, CT, DE, FL, GA, IL, KS, LA, MI, MN, MO, NJ, NY, NC, PA, TX, UT, VT, WV, WI 18 AL, CO, CT, DE, FL, GA, IL, LA, MI, MO, NJ, NY, PA, TX, UT, VT, WV, WI Roller-compacted concrete (RCC) 17 AL, AR, CO, DE, GA, IL, KS, LA, MN, MO, NH, NC, PA, SC, TN, TX, WV 12 AL, AR, CO, GA, IL, LA, MO, PA, SC, TN, TX, WV Table 9. Technology use by the states and availability of specifications and guidelines.

Survey of State Practices 95 HESC (in 27 states), LC (in 27 states), TCMC (in 25 states), and LMC (in 23 states). Conversely, PC, a technology developed in the early 1980s, has only six projects with ages between 6 to more than 10 years. This may be due to the fact that cities and counties build more PC projects than the state DOTs because PC is mostly used for parking pavements and much less in roadways. Challenges with Technology Use In response to a question related to challenges, problems, and distresses associated with the use of each technology or material, the states identified several key challenges; some were unique to a specific technology and others were common among several technologies. Experience of agency personnel, inspectors, and contractors was the most common challenge reported by a majority of the responding states. Other important challenges included higher cost of construc- tion, availability of materials locally, and mixture design and properties. Important challenges and problems with specific technologies are shown in Table 12. Other Concrete Technologies In this section, the survey questions pertained to other technologies not covered in the scope of the synthesis. Examples of “other” technologies in the questionnaire included innovative Technology No. of 1–5 Projects 6–10 Projects 11–25 Projects >25 Projects Ultrahigh-strength Concrete 10,000 psi (UHSC) 10 1 4 2 Self-consolidating concrete (SCC) 9 2 7 20 Internally cured concrete (ICC) 4 3 — 1 Ultrahigh-performance concrete (UHPC) 13 7 — 2 Temperature control of mass concrete (TCMC) 9 4 6 10 Precast concrete pavement (PCP) 10 4 1 2 Roller-compacted concrete (RCC) 11 4 — — Pervious concrete (PC) 8 2 2 1 High early strength concrete (HESC) 4 1 7 22 Very high early strength concrete (VHESC) (rapid- hardening concrete) 3 2 1 9 Lightweight concrete (LC) 12 4 4 7 Lightweight cellular/foamed concrete (LCC) 7 1 4 4 Latex-modified concrete (LMC) 7 3 7 10 Polymer concrete (Poly C) 5 3 2 7 States Note: Dash = no information provided in reference to indicate that the item was not used or applied. Table 10. Number of states that have constructed projects using the technologies.

96 Concrete Technology for Transportation Applications admixtures and nanomaterials to improve concrete properties and/or reduce shrinkage and cracking, performance-based mix designs, fibers, innovative deicing technologies, high-friction surface treatments, nontraditional SCMs, and nontraditional cementitious overlay and repair materials. Among the 40 responding DOTs, 14 states have worked on other technologies in experimen- tal or implementation stage, and indicated the technology use in pavements and/or structural applications. In addition, a number of those states have also developed specifications for the implemented “other” technologies. The following are some examples of other technologies in the experimental stage or that have been implemented in demonstration or planned projects: • Delaware, Illinois, West Virginia, and Wyoming are working with shrinkage-reducing materials to mitigate shrinkage cracking on bridge decks. • Florida, Maine, and Missouri are developing mixtures with steel and/or synthetic fibers for structural applications. • New York State has implemented the recently developed PEM guidance and has prepared a specification for use in projects (see Case Example in Chapter 4). • Florida, New York State, and Pennsylvania are working to optimize mixture ingredients using SCMs. Technology No. of States <2 Years 2–5 Years 6–10 Years >10 Years Ultrahigh-strength concrete 10,000 psi (UHSC) 1 4 1 9 Self-Consolidating Concrete (SCC) 3 3 4 25 Internally cured concrete (ICC) 3 2 — 2 Ultrahigh-performance concrete (UHPC) 1 9 1 9 Temperature control of mass concrete (TCMC) 1 1 10 15 Precast concrete pavement (PCP) 2 4 3 10 Roller-compacted concrete (RCC) 2 2 6 5 Pervious concrete (PC) 3 3 3 3 High early strength concrete (HESC) 1 3 9 18 Very high very early strength concrete (VHESC) (rapid- hardening concrete) — 3 5 6 Lightweight concrete (LC) — 6 4 23 Lightweight cellular/foamed concrete (LCC) 1 3 4 12 Latex-modified concrete (LMC) — 1 4 19 Polymer concrete (Poly C) — 2 4 5 Note: Dash = no information provided in reference to indicate that the item was not used or applied. Table 11. Number of states reporting project service lives.

Survey of State Practices 97 • Delaware and West Virginia have implemented, with success, the high surface friction technology. • Florida is developing concrete mixtures using recycled asphalt, while Missouri is using RCAs in pavement mixtures. • Delaware is evaluating some proprietary materials for use in UHPC mixtures. • Kansas has implemented the air void analyzer to evaluate air content in concrete for freeze- thaw resistance. In a similar effort, Vermont is experimenting with the SAM to determine if the internal air structure is sufficient to protect the concrete from adverse effects of freeze-thaw. • Louisiana has implemented the surface resistivity test to evaluate the long-term durability of mixtures used in bridge decks. • New York State is testing alternative deicing salts. Most of the concerns and challenges that states reported when using the above technologies were related to cost, industry acceptance, and lack of information on the potential long-term performance of the technology. Depletion of Quality Aggregates In this section the states were asked whether they had a problem with availability of quality aggregates presently or would have in the future. Florida, Kansas, and Maine reported currently experiencing shortage of quality aggregates. Thirteen other states predicted that there could be Technology Important Challenges and Problems Ultrahigh-strength concrete 10,000 psi (UHSC) QA/QC issues and cracking Self-consolidating concrete (SCC) Segregation, QA/QC issues, and appropriate aggregate size Internally cured concrete (ICC) Availability of lightweight aggregate and moisture conditioning Ultrahigh-performance concrete (UHPC) Availability of nonproprietary systems; surface preparation and joint forming Temperature control of mass concrete (TCMC) Insulation and other temperature control requirements and implementation; inspection and data interpretation Precast concrete pavement (PCP) Base-layer preparation; long-term performance and maintenance Roller-compacted concrete (RCC) Achieving proper density and surface roughness Pervious concrete (PC) Mixture design issue; surface smoothness and freeze-thaw durability High early strength concrete (HESC) Premature cracking; maintaining mixture workability; balancing durability needs with early strength Very high early strength concrete (VHESC) (rapid- hardening concrete) Premature setting; heat generation and shrinkage; production handling and placement issues Lightweight concrete (LC) Aggregate availability; storage and conditioning; and curing and longevity Lightweight cellular/foamed concrete (LCC) Availability of suppliers and equipment; mixture variability; maintaining required density Latex-modified concrete (LMC) Bonding and delamination issue and surface smoothness Polymer concrete (Poly C) Surface separation; poor ride quality Table 12. Important challenges and problems with technologies.

98 Concrete Technology for Transportation Applications a shortage of quality aggregates in the future. The remaining 24 states did not have an issue with quality aggregate availability now nor predicted a shortage in the future. Table 13 shows how the various states responded. Some of the solutions to address shortage of quality aggregates offered by the states included conducting research to extend service life of their transportation facilities (12 states), import- ing quality aggregates (9 states), modifying specifications and mixtures to allow the use of noncomplying or reactive aggregates in nonstructural applications (9 states), and using RCAs in concrete mixtures (7 states). Other suggestions included restricting the use of limestone and other aggregates to high-quality mixtures and encouraging more mining of aggregates locally. Shortage of Fly Ash With the abundance of the less-expensive natural gas alternatives to power generating plants, many coal-powered plants are gradually being phased out. This has resulted in a shortage of fly State DOT Shortage of Quality Aggregate Shortage of Fly Ash Yes Now In the Future No Yes Now In the Future No Alabama X X Arizona X X Arkansas X X Colorado X X Connecticut X X Delaware X X Florida X X Georgia X X Idaho X X Illinois X X Kansas X X Kentucky X X Louisiana X X Maine X X Massachusetts X X Michigan X X Minnesota X X Missouri X X Mississippi X X Montana X X Nebraska X X New Hampshire X X New Jersey X X New York X X North Carolina X X North Dakota X X Ohio X X Oregon X X Pennsylvania X X Rhode Island X X South Carolina X X South Dakota X X Tennessee X X Texas X X Utah X X Vermont X X Washington X X West Virginia X X Wisconsin X X Wyoming X X Total 3 13 24 13 16 11 Table 13. Shortage of quality aggregate and fly ash.

Survey of State Practices 99 ash that is used in concrete mixtures to enhance the long-term durability of structures. In this section of the questionnaire, states were asked whether they are experiencing a shortage of fly ash, presently or predict future shortages. Table 13 shows that 13 states are presently experienc- ing a shortage of fly ash, another 16 states predicted future shortages, and the remaining 11 states do not anticipate shortages. Among the solutions suggested in the responses, 22 states agreed on the need to expand the use of slag and increase its quantity in concrete mixtures. Fifteen states would expand the use of other pozzolans such as metakaolin. Six states would import fly ash and apply, if needed, a second-stage carbon removal process to bring the LOI content to within acceptable limits before their use in concrete. Other notable responses included conducting research to use alternative pozzolans such as rice husk ash, further processing of bottom ash, and allowing contractors to switch fly ash supplies between approved sources in ongoing projects. Use of Recyclable and Reclaimed Materials Table 14 shows the responses to the questions related to the use of RCA and other landfilled or reclaimed materials. Fifteen states use RCA in pavements and only five states use it in structural applications as well. The majority of the responding states do not use RCA in pave- ments (22 states). Among the states that use RCA in pavement mixtures, the RCA replacement percentage used ranges from 10% to 50%. Responses on RCA proportions in structural concrete applications were inconclusive. With respect to specifications, two states had stand-alone RCA specifications, six states incorporate RCA in their aggregate specifications, and one state uses project special provisions when incorporating RCA in concrete mixtures. In addition, a number of states have conducted research or applied in experimental projects other reclaimed materials such as granulated glass, tire rubber, bottom ash, construction debris, biomass ash, solid waste ash, and plastic bottle fibers, as shown in Table 14. However, these materials have had very limited, if any, use in concrete application, except ground tire rubber, which is routinely used in asphalt mixes for roadway applications. Barriers to Technology Implementation The survey asked the state DOTs about their opinions on a list of perceived barriers to imple- mentation of concrete technologies and any others the barriers they may be concerned with. The state responses and number responding were as follows: • Technology not sufficiently proven to be adopted (30). • Too expensive to use (28). • Not enough training to use the technology (27). • No specifications or construction guidelines available (23). • Industry resistance (21). • Not sufficient time available to be devoted to new technologies (16). • Bad experience with their construction or performance (13). • Resistance to change or to explore new technologies (12). • Weather conditions not permitting (5). Other notable responses include the following: • Lack of experience by agency and local industry. • Concern about potential reduction in concrete mixture quality. • Ability to assess long-term concrete durability with some technologies. • Implementation challenges. • Time and cost-effectiveness.

100 Concrete Technology for Transportation Applications The responses point to important gaps in technology transfer to assist some states in imple- mentation of new and innovative concrete technologies. Other barriers to implementation include fragmented training efforts, negative perception of reliability, concerns about mixture integrity and long-term performance, industry and agency reluctance, as well as cost and time availability to pay attention to new technologies. Case Examples At the end of the survey the respondents were asked if they would agree to be interviewed on certain aspects of their responses to formulate a case example from their state DOT. State DOT Use of Recycled Aggregate Reclaimed Materials Pavements Structures None None Alabama X X X Arizona X X Arkansas X X Colorado X X Connecticut X X X Delaware X X Florida X Georgia X Use of Other Landfilled or Materials Glass, tire rubber, solid waste ash, bottom ash, biomass ash Tire rubber, construction debris, plastic bottle fibers Idaho X X Illinois X X X Kansas X X Kentucky X X Louisiana X X Maine X X Massachusetts X X Michigan X X Minnesota X X Missouri X X Mississippi X X Montana X X Nebraska X X New Hampshire X X New Jersey X X New York X X Glass, solid waste ash, bottom ash North Carolina X Tire rubber, bottom ash North Dakota X X Ohio X X Oregon X Tire rubber Pennsylvania X X Rhode Island X Plastic bottle fibers South Carolina X X South Dakota X X Tennessee X Texas X X X Utah X Vermont X Washington X X West Virginia X X Wisconsin X Glass, tire rubber, bottom ash Wyoming X X Total 15 5 22 7 33 Table 14. Use of RCA and landfilled or reclaimed materials.

Survey of State Practices 101 An encouraging 24 respondents indicated willingness for additional interviews to prepare case examples for their respective states. Five case examples were received from Florida, Illinois, Missouri, New York, and Tennessee, and are presented in Chapter 4. Lessons Learned from Survey Results The survey was very helpful in collecting useful information from the DOTs on the state of the practice with various technologies, considering that the DOTs are the main users of these technologies. Results of the survey provided an understanding of the states’ practices, including level of implementation, applications, performance, challenges, and barriers to wider implementation. Based on analysis of the survey responses, several issues emerged. For example, most state DOTs are primarily interested in technologies to accelerate construction and/or repairs of bridges and pavements, to achieve the required consolidated strength in heavily reinforced forms, and to reduce cracking in mass concrete. Technologies such as SCC, HESC, VHESC, LMC, TCMC, and ICC serve these purposes. Some DOTs are considering use of fairly new technologies developed in recent years, such as UHPC, PCP, and ICC in demonstration or in actual projects. Other states have used more traditional technologies such as RCC, PC, and LC in new highway applications. However, with implementation of the technologies in transpor- tation projects, the states have also experienced challenges related to inadequately qualified or experienced project personnel, QA/QC issues, and some short- and long-term poor perfor- mance on projects. Fourteen states are experimenting with or have implemented technologies other than those covered by this synthesis. Some of the technologies are proprietary but serve an important purpose; others are considered traditional but are being used in new applications. With respect to recycling, only 15 of the 40 states use RCAs in concrete mixtures. Also, only seven states have experimented with or used, on a limited basis, other landfilled or reclaimed materials. The states also pointed out many barriers to implementation of traditional (but new to the state) or new technologies. The majority of the respondents cited three main barriers: (1) tech- nology not proven, (2) high cost, and (3) inadequate training. There were many states that also cited other important barriers such as industry and agency reluctance, time availability to devote to new technologies, and questions about long-term performance.