Boston University Center for Photonics Research

GEI provided geotechnical and environmental design and construction services for a new, 9-story classroom, office, and research laboratory building on the main campus of Boston University.

The site is located in a congested urban area surrounded by the Massachusetts Turnpike, two adjacent multi-story brick buildings, and narrow city streets. GEI evaluated the subsurface conditions for foundation design and to characterize the site soils for off-site disposal. Based on these investigations, GEI provided recommendations for pile foundation and mat foundation alternatives. The mat foundation alternative was selected based on an estimated cost savings of $1 million and design team concurrence that post-construction settlements could be accommodated. With the base of the mat foundation located up to 6 feet below the granite block footings of an adjacent brick building, jet-grouting techniques were used for underpinning. The excavation for the new building was supported using soldier piles and lagging with one to two levels of tiebacks.

Construction-phase services provided by GEI included preparation of bid packages and geotechnical observation of excavation support, underpinning, and soil and groundwater management activities.

GEI’s environmental work on the project included installation of groundwater monitoring wells and coring through the basement floor slabs of former buildings on the site to collect soil samples for laboratory chemical analysis. Based on the investigation, GEI developed a soil management plan to allow off-site disposal of most of the excavated soil as urban fill. GEI pre-screened soil samples so the contractor could excavate the soil without delay from the congested site.

GEI also provided oversight during the cleaning and removal of four underground storage tanks (USTs) encountered during demolition and excavation. One UST, located beneath the floor of the existing adjacent building, was tested and abandoned in place.