Jet Grouting for Mass Treatment to Support an Aggregate Stockpile Building over Very Soft Clays

A gravel storage building and distribution facility was planned for construction at the West Parr yard located in the Port of Richmond, California. The general subsurface profile consists of a fill layer overlying a lens of young bay mud, a soft to med stiff silty clay and clayey silt. Below that lied a deeper dense clayey sand and stiff clay layer. The ground water table elevation observed in borings was approximately 7 to 10 feet below the current ground surface. Loads in excess of 3,500 psf would be applied to these strata and relatively tight settlements tolerances were necessitated to maintain functionality of the building’s conveyor systems. Deep pile foundations were considered but due to the excessive costs and operational challenges, it was elected to implement a ground modification system, jet grout columns, to transfer the loads through the undocumented fill and young bay muds, to the more competent, stiff clay layer below