Interface Shear Strength of Geosynthetic Clay Liner (GCL) and Residual Soil

Abstract

In this study, direct shear box with dimension of 100 mm x 100 mm was used to determine interface shear strength of a GCL and compacted residual soil at optimum moisture content. The tests were carried out using dry GCL sample at shearing rate of 0.5 mm/min. Normal stresses used were between 100 kPa to 300 kPa to represent the depth of 20 meters of solid waste (15 kN/m3). The needle-punched GCL was tested for both sides, woven and non-woven. Results showed that the residual soil, classified as CL according to the Unified Soil Classification System (USCS) with a hydraulic conductivity of 7.05 to 5.54 x 10-9 m/s, was suitable to be used as compacted clay liner (CCL). Test results on the interface shear strength of woven and non-woven GCL with residual soil in terms of internal friction angle were 33° and 37°, respectively.