Transmissivity Behavior of Layered Needlepunched Nonwoven Geotextiles

Abstract

Needlepunched nonwoven geotextiles contain considerable void space that is available for liquid transmission. Compressing a geotextile reduces its in-plane and cross-plane liquid flow because it alters the fabric's pore structure. In this study, we investigate single-fiber and layered needlepunched nonwoven geotextiles as a function of various needlepunching parameters and fiber linear density. We also evaluate the transmissivity parameter β, which describes the transmissivity property of needlepunched nonwoven geotextiles. Experimental results indicate that these transmissivities decrease to a constant value with increasing normal stress. The transmissivity behavior of needlepunched non woven geotextiles depends on raw material characteristics, needlepunching parameters, and normal stress. This study also proposes relationships to predict the transmissivity behavior of two needlepunched nonwoven geotextiles in parallel.