This paper presents a review of two models (i.e., arching and lateral squeezing) developed for predicting earth pressures in soil-bentonite (SB) cutoff walls. The assumptions of these existing models are discussed, a modified lateral squeezing (MLS) model is presented, and all three models are compared based on predicted horizontal stresses for representative field conditions. Each model predicts that the stress distribution within a SB cutoff wall may be considerably lower than a geostatic distribution, particularly at depth. The arching model yields the lowest stress distribution but may underestimate the true distribution due to the assumption of rigid trench sidewalls. The MLS model (1) allows sidewall deformation and (2) accounts for the stress-dependent nature of SB backfill compressibility. The study also finds that additional model development is needed to characterize the stress state of a SB cutoff wall in three dimensions.
Strength and Permeability of a Deep Soil Bentonite Slurry Wall
In 2006, a Soil Bentonite (SB) slurry wall was constructed at a brownfield redevelopment of a former steel mill site in Mayfield, NSW Australia. At this site, the slurry wall is designed to block groundwater