Prediction of permanent deformation of foamed and emulsified sulfur asphalt soils mixes

This paper presents a study carried out to evaluate and compare the permanent deformation of marginal soils. Under consideration were marl, sabkha and dune sand stabilized with foamed and emulsified sulfur asphalt (FSA, ESA) with mixes of the same soils stabilized with conventional foamed and emulsified asphalt (FA, EA) for road base construction. Designed mixes at their optimum asphalt content were evaluated for the dynamic resilient modulus (M_R) at 22°C and 40°C and dynamic triaxial at three levels of deviatoric stress and at 22°C and 40°C. The wheel tracking (WT) test was carried out at 22°C. Permanent deformation of stabilized mixes with optimum binder contents was modeled and simulated using dynamic triaxial and WT tests. The developed models were calibrated to predict rutting using VESYS 5W software. Results indicated that the FSA increased rutting resistance as compared to conventional FA mixes. On the other hand, ESA increased the rutting susceptibility of marl soil as compared to EA. The calibrated models of rutting prediction were found to predict the rut depth with 90% accuracy.