The primary objective of this research is to study the permanent deformation behavior of a granular soil. The permanent deformation behavior of granular soils is strongly related to the rut depth development in flexible pavements. Repeated Load Triaxial (RLT) tests have the ability to simulate the cyclic pavement loading on the granular materials. However, no test standard is currently available. A comprehensive laboratory experimental work was carried out in this study on a poorly graded sand. The experimental work included resilient modulus tests and both single-stage and multi-stage RLT tests. The analysis of the permanent deformation of the sand was carried out by statistical analysis. A regression model was developed to describe the permanent strain accumulation with the number of load cycles at different stress conditions. A test procedure is proposed to for determining the material parameters for the proposed model.Civil Engineerin
