Non-destructive strength and stiffness evaluation of cement-stabilised granular lateritic soils

Modulus of pavement materials is an important input parameter for the mechanistic design of pavements. As the bound layers such as cement-stabilised materials fail in flexure, flexural modulus (FM) is generally used as the modulus of stabilised material for the analysis of pavements. FM is determined from four-point bending tests under cyclic loading, but this process is a time-consuming exercise and therefore non-destructive method such as ultrasonic pulse velocity test (UPV test) may be employed for rapid determination of the modulus of elasticity of the material. In this study, ultrasonic pulse velocity of cement-stabilised granular lateritic soil (CLS) samples was determined using the UPV test and were correlated with the compressive strength, flexural strength and FM of 28-days cured stabilised specimens. It has been observed that the variation in pulse velocity determined from the UPV test shows good agreement with the variation of compressive strength and flexural strength of the stabilised lateritic granular soil samples considered in the study. Correlation was also established between the FM determined from the cyclic flexural test and constrained modulus determined from the UPV test on CLS beam samples.