Response of Sand Reinforced with Multi-Oriented Plastic Hexa-Pods

Abstract

The concept of using strips, grids, and sheets for reinforcing soil masses was introduced by Henry Vidal in 1969. Since then, a large variety of materials such as steel bars, tire shreds, polypropylene, polyester, glass fibers, coir, jute fibers etc. have been widely added to the soil mass randomly or in a regular, oriented manner. A detailed review of the literature on soil stabilization using geosynthetics revealed that the conventional reinforcements in use were two dimensional, in the form of strips with negligible widths or in the form of sheets. In this investigation, a new concept of multi-oriented plastic reinforcement (hexa-pods), is discussed. A systematic and comprehensive set of undrained triaxial compression tests was conducted on unreinforced and reinforced fine, medium and coarse sands, with the confining pressure, volume ratio of hexa-pods, number of layers and hexa-pod orientation as the variables. Random addition of plastic hexa-pods resulted in an increase in the peak deviatoric stresses, and increased value of friction angles. The hexa-pods also changed the brittle behavior of unreinforced sand samples to ductile ones.