In October 2017, American Bridge Company undertook a vital project to replace 32 of the 108 steel anchor cables on the Interstate 90 floating bridges. These critical cables, essential for stabilizing the structure against the forces of current, wind, and traffic, require replacement every 25 to 30 years due to corrosion, rust, and fraying.
The extensive project involved replacing approximately three miles of 2-3/8″ steel cable, with individual cable lengths ranging from 335 to 745 feet. For the final stages of installation and tensioning, large barge winches were employed. These specialized winches were custom-designed and built by Finnoe Design, a national company based in Spokane renowned for their structural design-build expertise, with a portfolio including projects like the San Francisco-Oakland Bay Bridge and the Margaret McDermott Bridge in Dallas.
As part of this complex operation, ControlFreek leveraged SEW/Eurodrive technology, utilizing a Variable Frequency Drive (VFD) with advanced torque control. This innovative approach ensured the cable was consistently pulled and fed at a constant tension, preventing it from going slack or inadvertently moving the boat or divers, even amidst the challenging conditions of waves and windy days on the lake.