Modeling of Unreinforced and Reinforced Pavement Composite Material Using HISS Model (RESEARCH NOTE)

With the advent of high strength geogrids, the interest of civil engineers in using geosynthetics as reinforcement material in pavement construction has increased. An experimental study is carried out at IIT Delhi to understand the effect of geogrid in unpaved roads. Behavior of composite material, which comprises of Yamuna sand as subgrade and Water Bound Macadam (WBM) as base course is studied with and without geogrid reinforcement under drained conditions. A geogrid is used as reinforcing material. Drained triaxial tests were performed at three different confining pressures of 50, 100 and 200 kPa on both unreinforced composite and reinforced composite materials of specimen size 100mm diameter and 200mm height. Hierarchical single surface (HISS) model developed by Desai and co-workers is used to model the unreinforced and reinforced composite material. A computer program PARA6 is used to calculate the various parameters and to back predict the stress-strain-volume change behavior of unreinforced and reinforced composite materials. The predicted results match closely with the observed results.