GEODesign served as the geotechnical engineer consultant for the Larchmont Yacht Club improvements, which included the redesign of a pool and nearly a 100 year old seawall. The pool redesign includes areas for different activities such as diving, competitive swimming, and general swimming. To facilitate the new pool design the existing grade on the land side of the seawall was raised to match the top of the seawall, resulting in a changed loading condition to the existing seawall.
The Solutions Unearthed
- Most notably, GEODesign performed stability analyses for the existing and proposed seawall loading conditions. This task was particularly challenging due to the age of the seawall and varying design cases that accounted for both changes in grade and tidal fluctuations of the Larchmont Harbor. The seawall evaluation included a comprehensive review of historic drawings, performance of water borings to estimate the soil conditions at and below the bottom of the seawall, and an assessment of the seawall integrity by visual inspection.
- Test borings were performed to provide geotechnical engineering recommendations for the Clubhouse extension and filling the existing pool. The recommendations included shallow foundations with an allowable bearing capacity, seismic analyses, design soil parameters, excavation considerations, temporary groundwater control, subgrade preparation, and backfill and compaction requirements.
- A relatively large amount of fill was required to raise the grade within the existing pool. GEODesign reviewed the details of the proposed backfill, which included the borrow source location, material type, sieve analyses, and Proctor test results. GEODesign performed construction inspections for the placement and compaction of backfill and in-place density testing to confirm that the required percent compaction was achieved.
Client: Larchmont Yacht Club | Stoll Architects