Southern Colorado
Project Type: Underpinning & Repair
Division: Commercial
Service: Helical & Resistance Piers
Severe rains oversaturated deep fill and four critical transformer pads settled up to six inches. High voltage power lines coming to and from the transformers were at risk of being impacted. The general contractor hired Straight Line to stabilize and lift the transformers to level.
At each transformer, an L 8x8x3/4 angle was fastened to the existing pad, and underpinning brackets were welded in place. Two 2-7/8in helicals with 8in helix were placed as near the ends as possible (avoiding transformer lines).
Pads were then lifted to level position (recovery was limited to reduce stress on electrical cabling) and void spaces were filled with a soil-cement grout.
Down time at the facility was estimated to run at $1 million/hr, so the facility was placed on emergency generator power during critical helical driving and lifting operations. All work was performed in a two day (Fri-Sat) period.