Laboratory Research on Resilient Modulus of Lime-Stabilized Soil

Subgrade soils are important materials to support highways. For the past few decades, the resilient modulus (M_R) has been used for characterizing the stress-strain behavior of subgrades subjected to repeated vehicle loadings. Actually, instead of natural soils, lime-stabilized soils were applied widely to improve subgrade performance in wetting areas; but, M_R of lime-stabilized soil was not investigated sufficiently. In this paper, to estimate the influence of stress state, moisture content and compaction energy on M_R, specimens were compacted at different water contents (w_opt and w_opt±3%) with relative compaction of 90, 94 and 96%. Then, a series of repeated triaxial tests was carried out with confining pressures of 15, 30, 45 and 60 kPa, and deviator stresses of 60, 75, 95 and 125 kPa. Finally, results were fit to the three-parameter model recommended in NCHRP1-28A to determine the k_1-3 coefficients. It was found that the predicted regression coefficients compared well with measured ones.