Pile Load Testing – Hillsboro County Courthouse, Manchester, NH

August 26, 2010

Project: The existing Hillsboro County Courthouse in Manchester, New Hampshire was originally built upon driven concrete-filled steel pipe piles. Recent renovations included the construction of several new steel beams, placing additional weight to some of the existing pile-supported foundations. The piles were driven almost 50 years ago and no pile driving records or engineering details were available for review. The current design engineers were not sure of the pile capacities and needed to verify this to complete the design work.

Load Testing: Engineered Foundation Technologies provided a unique concept for the project and was subsequently awarded the project. A doubly-restrained shoring system was built around the pile cap, using helical piles to provide both the uplift and compression loads. Once the shoring was in place, a section of the driven pile was cut free from the foundation. A specialty jack was inserted into the cut-out section to then load the pile.

Deflection readings were taken during the loading process. The loading curve was subsequently produced from EFT’s load test, greatly helping the engineers determine the actual pile capacity. After the test was complete, the test pile was structurally rehabilitated and re-attached to the foundation system.

“(EFT) came in and did a terrific job with the testing program. Their successful execution of the pile testing got our project going in the right direction.”

Adam Kreitman – TLT Construction Corporation