Anderson Drilling was contracted to construct medium diameter drilled shaft foundations to support the expansion to the existing multi-use Qualcomm Stadium located in the Mission Valley area of San Diego. The project included a full scope installation of (92) drilled shafts ranging from 3 feet to 6 feet in diameter and up to 94 feet in depth. The accelerated schedule required that all drilled shaft installation be complete with equipment moved off the site within 3 weeks of the start date.

The subsurface conditions consisted of silty to sandy man-placed fill overlying natural alluvium that contained lightly cemented cobble that graded into sedimentary formational materials at varying depths. Groundwater was encountered at approximately 45 feet below grade. Synthetic polymer slurry was used to promote shaft sidewall stability and prevent caving. Oversized corrugated surge chamber liners were necessary to provide the necessary hydrostatic head pressure above the natural water table, as well as offer stable soils at grade.