From 1844 to 1999, the Seneca Knitting Mill produced woolen goods and supported many residents of Seneca Falls for multiple generations. After closing its doors in 1999, the historic building sat vacant until 2007, when it was purchased to be used as the new location for the National Women’s Hall of Fame. The building required extensive renovations and modernizations. One major change to the building was the addition of an elevator on the exterior.
Using piles, the foundations for the elevator shaft were designed to bear on limestone rock at depths of 10-12 feet below surface elevation. Due to the high compression load as well as lateral loads, our team designed a foundation system using STELCOR drilled-in displacement micro-piles. The 7-inch diameter STELCOR piles were designed to achieve their 100 KIP working load bearing in weathered shale, the grout column was designed to give the pile sufficient rigidity to resist lateral loads.
In order to perform compression testing on our micro-pile design CMI utilized hollow bar as reaction piles, because with only 10' of overburden on top of the weathered shale helical piles would not be able to resist the tension loads needed. Hollow bar anchors are a threaded micro-pile outfitted with a sacrificial drill bit, and like the name suggests, have a hollow center. As the pile is drilled in, debris from the bottom of the hole is forced to the surface using air, water, or a slurry grout mix. Once the pile has reached its required elevation, grout is pumped from the tip of the pile, creating a grout column around the hollow bar. Our team installed hollow bar to depths of 30 feet and completed the load test to the requested ultimate load.
Above: Hollow bar being installed to be used as reaction piles.
After the completion of the load test, the 5 STELCOR piles were successfully installed to depths of about 12 feet for the new elevator shaft. CMI’s designed team will always create innovative solutions for all types of testing and project conditions. Additionally, CMI completed this project efficiently without damaging existing infrastructure in the surrounding area.
Above: One of the 5 STELCOR piles being installed
Below: A recent photo of the completed project (Photo credit LeChase Construction)
