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41 3 Sample B1 2.22 % 2.5 2.15 % 2 STRAIN (%) REFERENCE TEMPERATURE - 23C 1.5 100 Yrs 500 psi Stress 1 50 Yrs 0.5 0 -4 -3 -2 -1 0 1 2 3 4 5 6 7 LOG TIME (hr) Figure 40. Creep strain master curve for Sample B1. 200000 180000 Sample B1 160000 50 Yrs 100 Yrs CREEP MODULUS (psi) 140000 120000 100000 80000 60000 23,250 psi 40000 22,531 psi REFERENCE TEMPERATURE - 23C 20000 500 psi Stress 0 -3 -2 -1 0 1 2 3 4 5 6 7 8 LOG TIME (hr) Figure 41. Creep modulus master curve for Sample B1. Next, the SIM was used to determine the creep properties The raw data and the master creep curves for these samples of the samples when placed under an applied stress of 500 psi. are found in Appendix D, Section D.12. These results will be This involves a series of 10,000 second (166 min) creep tests, used to evaluate how one would design with recycled formu- each done on the same test specimen and separated by 7C lations in the context of Section 12 of the AASHTO LRFD in temperature. In this case, creep curves were generated Bridge Design Specifications (15). from 20C to 83C. The raw data are then shifted through TTS to generate a master creep curve at a reference tempera- Long-Term Stress-Crack Resistance ture (23C). Creep strain and creep modulus master curves for sample B1 (100% VR1) are shown in Figures 40 and 41, The six final candidate formulations and the PCR MCR resin and all of the results are shown in Table 17. were evaluated by the BFF test under the three sets of conditions Table 17. Long-term creep strain and creep modulus under 500 psi of stress. Creep Strain Creep Modulus Sample 50 year 100 year 50 year 100 year B1 2.15 2.22 23,250 22,531 A2 2.07 2.14 24,160 23,358 L5 2.22 2.30 22,549 21,719 A5 2.19 2.26 22,821 22,091 B3 2.24 2.32 22,300 21,532 B5 2.64 2.72 18,965 18,406