The Grays on Pennsylvania Avenue consists of 118 residential units, ground floor retail space, and a single-level of below grade parking.
Test borings indicated a very loose to medium dense silty sand at planned footing subgrade elevations. Standard penetration resistance at bearing elevations ranged between 2 and 16 bpf. Groundwater was encountered at all footing subgrade elevations. The maximum column and the wall loads are 330 kips and 9 kips, respectively.
A total of 531 Geopier Impact elements were installed at footing locations in the basement excavation and along the perimeter excavation support. To increase the bearing capacity and meet required total and differential settlement design criteria, tremie grout was added to provide additional displacement Impact element stiffness.