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From page 46... ...
Individual responses to each ques tion and specific comments or exceptions to some of the questions are presented in Appendix B Responses to the results of survey questions are shown under the general topics shown here: • Contact information • State DOTs' use of SCMs in concrete • Applications in which state DOT specification allows the use of SCMs • Conditions that require the use of SCMs in concrete • Types of SCMs in concrete • Percentage of SCMs used in concrete mixtures • NPs used in concrete mixtures • Ternary and quaternary SCM mixtures • Acceptance strength and other test requirements for concrete with ASCMs • SCMs in concrete with Type IL cement • Availability of fly ash • Alternative SCMs • Case example interviews Contact Information The question asked for the contact information of the respondent.
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From page 47... ...
State DOTs' Use of SCMs in Concrete All 43 responding DOTs allow the use of SCMs in concrete mixtures. Thirty-five allow SCMs as additives to the concrete mixture or as blends in cements.
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From page 48... ...
Percentage of SCMs Used in Concrete Mixtures Percentage of SCMs Used in Concrete for Pavement Applications Table 7 and Figure 21 show replacement rates of SCMs for Portland cement in concrete for pavements. Most responding DOTs use 20% fly ash Class F, 50% slag cement, and less than 10% silica fume.
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From page 49... ...
State DOT Practices 49 40 40 37 35 35 30 28 Responses 25 19 20 16 15 15 11 10 10 10 5 3 0 ice lin y sF sC sk e e ag rs h cla al m as hu he ao as as m Sl sh fu d d pu Cl Ot Cl ak ce ne d a te lic ne et Ri d es lci Si ne M lci rv Ca lci Ca Ha Ca Total Responses: 41 Figure 20. Use of conventional SCMs, harvested coal ash, NPs, and other pozzolans in concrete. Table 7. Percentage of conventional SCMs permitted in pavement concrete.
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From page 50... ...
Natural Pozzolans Used in Concrete Mixtures Twenty-three of the 41 responding DOTs indicated that NPs are either not permitted or not included in their specifications. However, 18 other states allow the use of one or more NPs and included specific percentage replacement rates for concrete mixtures (Table 9)
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From page 51... ...
State DOT Practices 51 Table 8. Percentage of conventional SCMs permitted in structures. State <10% 10%–15% 20% 25% 30% 40% 50% 60% Other % Not Used DOT ND, WI, SD, ND, SD, ND, IA, TN, SD, MT, ME, MI, PR, CO, TX, WA, WI, IL, MS WI, GA, SC, NE, ND, IA, MN, OR, PA, TX, FL MN, CA, MO, IL, MO, AZ, NE, MO, RI, NC, FL NY, VT, FL, DE, KY, CT, AZ, KY, AL, TX, IL, MS, Fly ash F MS, HI WV, NV, CT, NV, FL, MA, LA OH, IL, TX, OH, IL, UT FL, OK, TX, FL, MS, VA MS, VA, WV, OK WI, IL, WI, GA, WI, IA, SC, TN, WI, MT, WI, MI, PA, CO, FL WA, MN, SD, ND, MS MO, IL, AZ, CT, IA, AZ, MN, OR, FL NC, NY, ME, NE, FL, MS WV, OH, CT, WV, KY, RI, TX, LA NV, CA, Fly ash C IL, FL, OK, OH, IL, AL, IL, FL PR, VT, MS FL, OK, DE, VA, MS MA, UT, HI WI, IL, WI, IL, MS WI, NV, WI, NV, MT, MO, MI, PA, CO, ME, FL TN, NE, SD, ND, MS PR, IL, MS PR, IL, WI, KY, TX, DE, WA, SC, MN, CA, AZ, UT, MS CT, OH, MS, VA OR, GA, NY, VT, HI IL, TX, WV, RI, IL, FL, Slag MS NC, AL, LA TX, FL, OK, DE, MS, VA, MA MT, WA, WI, GA, WI, NV WI, NV, WI CO TN, ME SD, ND, MI, WI, AZ, KY, PR, IL, CT, CA, IA, SC, OR, MO, AL, OK MS NY, VT, NE, DE, MN, AZ, LA, MA MI, HI Silica KY, WV, fume RI, NC, OH, PR, IL, PA, TX, FL, VA, UT Total Responses: 41 20 15 Responses 10 5 0 Fly Ash F Fly ash C Slag Silica fume <10% 10%-15% 20%-25% 30% 40% 50% 60% Other % Not used Figure 22. Percentage of SCMs used in bridges and other structures.
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From page 52... ...
Ternary and Quaternary SCM Mixtures Ternary Mixtures in State DOT Specifications Twenty-six of the 33 responding DOTs allow the use ternary concrete mixtures in pavements and structures, as shown in Figure 23. Four states do not allow their use.
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From page 53... ...
10% + ≤ 20% + ≤ 50% + ≤ 20% + 20% + 30% + 40% + 10% + 15% + State DOT Other % Not Used 10% 10% 10% 20% 30% 30% 20% 50% 50% OR, FL MI, OR, FL RI, TX, TX, FL WA CO, MI, TN, SD, TX, FL FL WI, NY, ME, IA, Fly ash F OH, IL, AZ, WV, + Fly ash PA, OK, NC, CA, C LA PR, VT, MS, VA, UT OR, FL OR, PR, MI, IA, OR, WA, TN, MT, SD, ME, TX OR, TX RI, TX, FL MI, WI, AZ, WV, VA MN, NC, OK, MS, Fly ash + CA, NY, UT slag OH, VT, IL, PA, LA OR OR, WV, WA, WI, ME, MI, RI, TX, NC, CA, IA, AZ, Fly ash + FL, VA, NY, OH, PR, MS silica UT IL, PA, fume FL, OK, LA OR, AZ OR, WV, ME, OR, WA, MI, TN, SD, VT, VA RI, FL WI, NC, IA, PR, Slag + CA, NY, MS, UT silica OH, VT, fume IL, PA, TX, OK, LA OR OR, TX OR, TX IA, OR, FL FL WI, MN, TN, SD, TX NC, CA, ME, MI, NY, OH AZ, RI, Natural PR, VT, pozzolan + IL, PA, slag OK, MS, LA, VA, UT Total Responses: 29
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From page 54... ...
Louisiana allows combinations of SCMs not exceeding 50% for pavement and bridges and 70% for mass concrete mixtures, but limits silica fume to 10% in any SCM blend. Utah allows a blend of 25% a natural pozzolan and 5% fly ash.
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From page 55... ...
Tests Required by State DOT Specifications Many DOTs do not require special tests for concrete mixtures with SCMs. Sixteen state DOT specifications require surface resistivity tests, and 12 require direct chloride permeability tests.
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From page 56... ...
Type of Impact on Performance of Concrete with Type IL Cement Table 11 and Figure 29 present results from the 15 state DOT responses on the impact of SCMs on performance of Type IL concrete mixtures. The Illinois DOT's experience with using SCMs in concrete mixtures has been positive despite some incidents of delay in early strength develop ment.
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From page 57... ...
has been that, compared to regular Type I/II mixtures containing SCMs, SCMs in Type IL mixtures increase long-term concrete strength after minor adjustments. Availability of Fly Ash Fly Ash Shortage Experienced by State DOTs The majority of the responding DOTs, 25 out of 33, indicated that they had experienced shortages in the availability of fly ash during the previous 5 years or more, were experiencing shortages at the time of the survey, or anticipated shortages in the near future (Figure 30)
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From page 58... ...
Appendix B provides a list of actions by specific states to address shortages of fly ash. Alternative SCMs Use of ASCMs in Concrete Twenty of 33 DOTs indicated that they had no plans to use ASCMs, while six allow their use, and seven will consider using them in the future (Figure 32)
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From page 59... ...
More information on Colorado's allowed use of ASCMs is also included in the case examples. Table 12. Types of ASCMs permitted by some state DOTs.
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From page 60... ...
Also, eight respondents indicated that tests unique for ASCM concrete are not yet specified, and that tests required for conventional Table 13. Percentage of ASCMs used by state DOTs. Percent Ground Industrial or By- Percent Off- Other ASCMs Not Sure at Glass in Concrete Products Similar Specification (Not Present Time State to Fly Ash Meeting AASHTO M Pending DOT 295/ASTM C618-23)
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From page 61... ...
Field Trials of ASCMs Two state DOTs, those of Minnesota and Utah, indicated that they currently support field trials of ASCMs. (More details are provided in the MnDOT and UDOT case examples in Chapter 4.)
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From page 62... ...
Field Trials Planned by State DOTs to Evaluate ASCMs Figure 37 and Table 14 show responses from seven DOTs regarding planned field trials. The respondents plan to do field trials for pavements and bridges as well as mass concrete and park ing areas.
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From page 63... ...
Pavement bridge structure, mass concrete, and parking area. No Ohio trials yet.
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