Collaborative Foundation Value Engineering Redesign-Paper

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The Second Street Pavilion at Hackensack University Medical Center in New Jersey required deep foundations capable of supporting heavy axial, uplift, and lateral loads in variable fill, glacial soils, and shale bedrock. The original design specified large drilled shafts with long rock sockets, relying on side resistance.<br /><br />Keller, the foundation contractor, partnered with Foundation Test Group and the project stakeholders to develop a value-engineered alternative tailored to Keller’s equipment and construction experience. Additional borings characterized the shale, and two dedicated test shafts were installed and subjected to bi-directional axial and lateral load tests. The testing evaluated both stronger and weaker rock zones and measured shaft resistance and deformation.<br /><br />Results supported a revised design using a combination of rock-socket side shear and end bearing: allowable values of 10.0 ksf in side shear and 125 ksf in end bearing. Lateral testing also verified the required 75- and 100-kip loads and helped refine the design’s lateral soil-response parameters. The redesigned shafts used smaller diameters and shorter sockets than originally specified, while meeting project requirements.<br /><br />The approach reduced material, labor, and equipment costs, shortened construction time, and lowered the risk of striking underground utilities. Integrating the foundation and excavation-support plans also enabled efficient use of the same drilling equipment and crews. Careful scheduling and coordination accommodated testing, demolition, utilities, and hospital operations on a congested urban campus.<br /><br />The project demonstrates that early collaboration among the owner, designers, contractor, and testing specialists can turn an adequate foundation design into a more economical and constructible solution without compromising performance.

Keywords

Hackensack University Medical Center

Second Street Pavilion

deep foundations

drilled shafts

rock sockets

bi-directional load testing

axial loads

lateral loads

value engineering

shale bedrock