Experimental Studies to Evaluate Performance of Coconut Shell Mat as Cellular Confinement in Sandy Soils

Abstract

This study investigates the use of coconut shells as a sustainable reinforcement material to enhance the bearing capacity of sandy soil. Laboratory model tests were conducted to assess the performance of coconut shell-reinforced sand as a foundation medium. Different shell arrangement patterns were analyzed and compared with the performance of HDPE geocells. The results indicate that coconut shell reinforcement substantially increases soil bearing capacity, from 218 kPa in unreinforced sand beds to 414.5 kPa with coconut shell mat reinforcement. Coconut shell mats present a cost-effective and environmentally friendly alternative to commercial geocells. However, their limited durability in untreated form confines their application to short-term uses, emphasizing the necessity for proper treatment to support long-term applications. © The Author(s), under exclusive licence to Indian Geotechnical Society 2025.