Effect of Moisture Content and Dry Unit Weight on the Resilient Modulus of Sub grade Soils Predicted by Geogauge

Abstract

Subgrade soil characterization in tems of Resilient Modulus (MR) has become crucial for pavement design. For a new design, MR values are generally obtained by conducting repeated load triaxial tests on reconstituted/undisturbed cylindrical specimens. Because the test is complex and time-consuming, the non destructive in-situ tests such as geogauge are used for predicting resilient modulus from correlation equations. The present study focuses on to estimate resilient modulus of subgrade soils from non destructive insitu test geo gauge and to investigate the effect of moisture content and dry unit weight on the resilient characteristics of subgrade soil predicted by the geo gauge. Three soil types (BC soil, sand and morrum) and three levels of moisture contents - dry side, optimum, and wet side - were selected for these testings. A sensitivity analysis was performed to evaluate the effect of the change in resilient modulus, due to variations in dry unit weight and moisture content, on the overlay thickness