Northwell Health North Shore University Hospital Advanced Surgical Pavilion (ASP)

GZA provided geotechnical engineering services during the design and construction of the proposed Advanced Surgical Pavilion (ASP) facility.

Challenge

Non-homogeneous soil conditions throughout the site resulted in GZA recommending a mixed foundation system: shallow foundations after soil improvement and deep (micropile) foundations. The varying soil conditions required extensive settlement analysis, earthwork construction, groundwork improvements, and monitoring of adjacent structures during excavation and foundation construction. Underpinning and intensive support of excavation (SOE) was also required to facilitate construction adjacent to the abutting existing structure. Lastly, GZA consulted on stabilizing an existing retaining wall with tie backs to withstand added loading.
 

Solution

GZA planned and executed a geotechnical exploration program and provided geotechnical design and construction recommendations for the new building and site retaining walls. GZA recommended vibratory stone columns (vibro-piers) as a ground improvement technique to mitigate excessive post-construction settlements due to future foundation loads; this technique reinforces weaker strata and distributes foundation loads to underlying denser/stiffer strata. Micropile foundations were used for excessively high loads for pedestrian bridges and support of foundations close to existing foundations. GZA provided design and construction support for piles, retaining walls, and SOE elements and construction oversight services during installation of vibro-piers, earthwork construction, and foundation installation activities.
 

Benefit

GZA’s experience on numerous Northwell Health projects, developing geotechnical engineering solutions for complex site soil conditions, and providing support to the construction team during construction, were integral to the successful project execution and management of associated risks.