Performances of the Soil–Bentonite Cutoff Wall Composited with Geosynthetic Clay Liners: Large-Scale Model Tests and Numerical Simulations

The geosynthetic clay liner (GCL) overlap plays a key role in maintaining hydraulic performance of the barrier systems, e.g., bottom and cover systems. However, its influences on behavior vertical have been rarely investigated. This paper aims to address this issue using large-scale model test 3-dimensional finite element (FE) modeling. In test, GCL at width 500 mm was tested under constant head 1 m confining stress ranging from 10 150 kPa newly developed apparatus. Compared with flexible wall permeameter, apparatus could guarantee full field-scale be tested. Results showed that effective conductivity decreased 10−8 10−9 cm/s as increased kPa. addition supplemental bentonite paste between water-to-bentonite ratio 19:1 contributed reducing by 60% compared for without paste. breakthrough time soil-bentonite (SB) cutoff composited GCLs 64% longer comparison single SB wall. Additionally, after 50 years is made entire depth while no more than 0.9 composite overlap. With consideration groundwater table generally greater m, GCL–SB will exhibit good containing contaminants field, especially when applying