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81 Table 4.17. Typical results of Kelly ball tests (ASTM D 6024) in two bridge approach repairs. Southbound Northbound Time after Diameter of Kelly Time after Diameter of Kelly placement ball indentation placement ball indentation (h:m) (mm) (h:m) (mm) 0:10 114 0:09 122 0:22 99 0:19 108 0:33 97 0:30 95 0:42 89 1:07 95 0:56 76 1:30 89 field test was not to produce excavatable CLSM but rather to evaluate the in-situ moduli of the completed bridge approach develop a mixture that hardens quickly, allows for rapid con- sections. The SPA is an automated non-destructive device for struction and paving, and performs well over time, with little conducting the SASW tests in less than 1 minute (Nazarian or no settlement. et al. 1993). In analyzing the SASW results, a thickness of 80 mm was assigned to the hot-mix asphalt layer. The upper CLSM fill was assumed to have a thickness of 600 mm. The Monitoring of Field Performance remaining backfill above the native soil was the lower fill. Approximately 2 months after construction of the bridge Measurements were performed parallel with and perpendicu- approaches, a visual survey of the approaches was performed. lar to the direction of travel on the roadway. The average mod- No differential settlement of the bridge approach sections was uli measured along the profile are shown in Figure 4.21. The visible and the sections were performing very well. The "bump modulus of the asphalt pavement was quite uniform. How- at the end of the bridge" was essentially non-existent, which ever, the modulus of the CLSM backfill varied significantly. was a significant improvement over the condition of the This observation agrees with the measured variations in com- bridge approach sections prior to repair. At the time of this pressive strength quite well and supports the empirical rela- inspection, a seismic pavement analyzer (SPA) was used to tion typically used for conventional concrete, whereby the 60 50 40 Temperature (C) 30 Southbound Northbound 20 10 0 0 20 40 60 80 100 120 140 160 Time (hours) Figure 4.19. Heat generation in the center of rapid-setting CLSM bridge approach sections.