Waugh Chapel South, Building 11, Crofton, MD

This project is located in the southeastern corner of the Village South at Waugh Chapel development in Crofton, MD, which is constructed over top of a former sand and gravel mine. The mine has historically been reclaimed with stumps, fly ash, and both uncontrolled and controlled fills. In particular, Building 11 is situated over controlled fills (northern half of the building), and native soils (southern half of the building). Additionally, a berm was formerly present along the frontage of Crain Highway. GTA observed and tested the controlled fills in the vicinity of the building during the overall site reclamation activities. GTA provided foundation recommendations for this building during a previous exploration program for the overall site. At that point, the building was planned to consist of a relatively lightly loaded one-story building. GTA was retained to perform a design-phase exploration for the building, which was revised to a more heavily-loaded, three-story steel framed building. GTA’s exploration included two in-situ dilatometer soundings. The results of the DMT soundings allowed us to significantly increase the allowable bearing pressure that was previously assigned, based on Standard Penetration Test (SPT) data, resulting in reduced footing sizes, and construction cost savings.