An investigation was conducted to determine the life period of full-depth granular pavements in india. Benkelman beam deflections, rutting, cracking, and patching were measured on different test sections to calculate the performance of the pavements. A repeated-load-test apparatus was fabricated in the laboratory for testing the subgrade soils and water-bound macadam base to determine the elastic moduli under repeated triaxial stress conditions. A finite element computer program was developed to determine the stresses and strains in pavement layers and to correlate the pavement performance and the critical stress and strain values. The pavement surface deflections measured by benkelman beam are in close agreement with the values predicted by the computer program. From the repeated-load-test results, relationships were found between (a) the resilient modulus and the lateral pressure and (b) the resilient modulus and the sum of principal stresses. The equation developed for predicting the rut depth fromthe benkelman beam deflection data is in close agreement with that developed in the aasho road test. The rut depth was also related to the gravel surfacing depth and the cumulative axles. Finally, a regression equation for finding the lives of flexible pavements was established using the rut depth and subgrade vertical strain values. This paper appears in transportation research record no. 1307, Pavementanalysis, design, rehabilitation, and environmental factors 1991.
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