Load Testing of a 117-Year-Old Pile Raft-PPT Presentation

PPT Presentation

Pdf Summary

The presentation describes the assessment and reuse of the approximately 117-year-old foundations at the Gowanus Powerhouse, now being redeveloped as Powerhouse Arts in Brooklyn. The 2.5-acre project includes renovation of the turbine hall, reconstruction of the boiler house, and new site and waterfront improvements.<br /><br />The historic boiler house and turbine hall sit on six-foot-thick concrete rafts supported by timber piles spaced about five feet apart. Beneath them are fill, soft estuarine deposits, and glacial soils; investigations also identified voids under parts of the turbine hall.<br /><br />To meet requirements for foundation reuse, the project team inspected the existing foundations in test pits, investigated subsurface voids, and used expansive chemical grout to improve ground support. New York City’s Department of Buildings required mass load testing to evaluate how the pile groups performed under load. Two tests simulated proposed increases in building load: the boiler-house test applied 4,000 pounds per square foot against a 2,000-psf design increase, while the turbine-hall test applied 1,900 psf against a 950-psf increase. Both tests passed.<br /><br />The project demonstrates that carefully investigated and tested historic foundations can be adapted for new use. Reusing the existing pile rafts avoided the need for entirely new foundations, offering potential savings in cost, time, and materials while reducing environmental risks.

Keywords

Gowanus Powerhouse

foundation reuse

historic foundations

Brooklyn redevelopment

Powerhouse Arts

turbine hall

boiler house

timber piles

mass load testing

chemical grout