A.H. Beck constructs a soil bentonite cutoff wall using a hydraulic excavator and bentonite slurry to maintain sidewall stability in Gulfport, Mississippi.
A. H. Beck Foundation Company worked with Environmental Management Services to provide design input and construction of a soil bentonite cutoff wall. The 2,200 linear feet of cutoff wall was 3 feet thick and ranged in depth from 25 to 42 feet. The cutoff wall trench was excavated using a hydraulic excavator utilizing bentonite slurry to maintain sidewall stability in the trench prior to placing the engineered soil bentonite backfill.
Excavated and stockpiled on site soils, raw bentonite, and a hydrated bentonite mixture were mixed ex-situ utilizing scaled batching equipment. This mixing process allowed the mixture to be accurately proportioned with quality control measures to ensure that the soil bentonite backfill met the required permeability of the project specifications. The engineered backfill was placed into the open excavation via concrete pumping equipment and tremie methods.
