The U.S. Army Corps of Engineers Montgomery Dam Lift Gate in Pittsburgh, Pennsylvania, is the second busiest inland port in the nation. The gates were destroyed in a 2006 navigation accident and the new engineering solution was predicated on reusing the 1936 vintage gate-lifting machinery and ensuring the new gates would be readily adaptable to a future new-generation hydraulic lifting system. 

With the overall weight and center of gravity being a critical factor in the design of the new gates, the use of 3D modeling was essential. Bentley’s STAAD.Pro enabled a design that was more efficient, robust, redundant, and resilient than the original and also included the reuse of existing hoist machinery and its limited lifting capacity -- constraints imposed by compatibility with the geometry of the existing pier, alignment of lifting points, and mating of embedded metal sealing surfaces with sealing surface of the gate.