Geotechnical properties of lime-geogrid improved clayey subgrade under various moisture conditions
Soheil Jahandari, Zhong Tao, Mohammad Saberian, Mahdi Shariati, Jie Li, Masoumeh Abolhasani, Mostafa Kazemi, Aida Rahmani, Maria Rashidi
Abstract
This research evaluated the effect of different moisture conditions on the ductility, geotechnical and microstructural characteristics of the improved clayey subgrade with various lime contents and geogrid layers. The results of more than 120 tests showed that the combined application of lime and geogrid to the clayey subgrade significantly enhanced the ductility and geotechnical characteristics by increasing the moisture content up to an optimal value. It was observed that higher water pressure led to the separation of the geogrid layers from the improved subgrade; thus, the uniformity, consistency, and geotechnical properties were significantly reduced. Microstructural analysis showed that increasing the amounts of moisture more than the optimal values caused more voids which led to a substantial decrease in the geotechnical properties as well as the physical bonding between geogrid layers and lime-stabilised soil. Finally, a simple prediction model was developed to estimate the geotechnical characteristics of the improved clayey subgrade.