Bryn Mawr Hospital, Bryn Mawr, Pennsylvania

Overview: Mainline Health Real Estate invested heavily in expansions and upgrades to their Bryn Mawr Hospital campus in the western suburbs of Philadelphia. GeoStructures was involved in several phases of design and construction for various structures and improvements. This expansion, in particular, includes the development of Medical Office Building B (MOB B) and an eight-story parking structure. GeoStructures provided geotechnical design, construction monitoring, and stormwater management services for the project.

To characterize the subsurface soil and groundwater conditions across the medical campus, GeoStructures completed 65 test borings, 12 piezometers, numerous test pits, infiltration testing, and laboratory testing. For the 8-story parking structure with 2 levels below grade, we designed an innovative temporary-permanent soil nail shoring system. This system minimizes lateral earth pressure against the basement walls to achieve significant savings in the construction of 2 levels of underground parking. For foundation support, we used special settlement mitigating measures below heavily loaded column footings to facilitate the use of cost-effective shallow foundations and slab on grade.