Load Testing of a 117-Year-Old Pile Raft-Video

Video Transcription

Video Summary

Richard Lowe of Langan Engineering describes load-testing the century-old timber-pile foundations of Brooklyn’s historic Powerhouse, being adaptively reused beside the heavily contaminated Gowanus Canal. The six-foot-thick concrete raft rested on timber piles and contained hidden voids. Installing new foundations would have required costly, environmentally challenging excavation, so the project team sought approval to reuse the existing system.<br /><br />They excavated five test pits and found the piles in excellent condition, mapped and filled voids beneath the slab with expansive grout, and conducted two large-scale load tests using soil stockpiles. Automated monitoring tracked movement over several months. At the full design loads, the exterior test showed about half an inch of deflection and the interior test about one-eighth inch—results the team considered acceptable.<br /><br />The project demonstrated that careful investigation, ground improvement, and load testing can support safe, sustainable reuse of historic foundations while reducing construction time, cost, and environmental impact.

Keywords

Brooklyn Powerhouse

timber-pile foundations

load testing

adaptive reuse

Gowanus Canal