Geo Tech

The project includes partial demolition of the existing Salvation Army facility and construction of a 7,000± square foot building expansion. Subsurface conditions at the site consist of urban fill deposits underlain in succession by organic soils, natural sand deposits, and then natural silty clay. Design phase responsibilities included evaluation of the subsurface soil and groundwater conditions, engineering design, and report preparation.

Engineering studies included the evaluation of: potential settlement of existing foundations resulting from an increase in structural loads; support options for new foundations; settlement of new foundations resulting from consolidation of the buried organic and underlying soft silty clay deposits under the proposed loads; and downdrag forces on pile foundations.

Engineering recommendations included: reuse of existing foundations in conjunction with a new pressure injected footing system founded in the natural sand deposits to support the proposed building expansion; use of a combination of slab on grade and structural slab construction; seismic design criteria; and earthwork construction criteria including reuse on on-site urban fill materials, fill gradation criteria, and placement and compaction of fill. Recommendations pertaining to vibration monitoring and pre-construction surveys of the existing Salvation Army building and close urban abutters were also provided.

Northeast Geotechnical prepared a pressure injected footing installation specification for incorporation into the project documents. Earthwork specifications and project site and structural plans prepared by the project civil engineers were also reviewed to assess that our geotechnical engineering recommendations were properly interpreted and included.