Rockridge Geotechnical (RG) performed a geotechnical investigation and provided geotechnical services during the construction of a supportive housing complex at 180 Jones Street. The development is nine stories and contains 70 units, and it was constructed at-grade.

The primary geotechnical issues affecting the proposed development included: (1) the presence of loose to medium-dense fill beneath the site that is susceptible to excessive static settlement under new building loads, (2) providing adequate vertical and lateral support for the proposed building, and (3) the presence of neighboring structures with basement level(s) bordering the eastern and southern property lines. RG provided recommendations for the building to be supported by a mat foundation bearing on ground improved with drilled displacement columns. RG provided consultation during final design and construction permit application. RG also provided geotechnical observation and construction services during construction; these services included observation during the installation of the drilled displacement sand-cement column ground improvement system and subgrade preparation for the mat foundation.