Pittsburgh’s Commercial Street Bridge Replaced in Under 24 Hours
Installation technique minimizes disruption for road-going public When replacing an old bridge with new, time is always a critical factor – especially if the crossing serves as a main route in and out of a busy city. The original Pittsburgh Commercial Street bridge went into construction in 1948 and was completed in 1951. Today, it is used by more than 100,000 vehicles every day. The concrete bridge went through three rehabilitations in its life, during 1980, 2006 and 2012 – but eventually needed to be replaced with a new structure that could carry permit loads. This major infrastructure project utilized Accelerated Bridge Construction (ABC) techniques. The replacement span was built beside the old bridge over a period of months, and then laterally slid into position immediately after the old bridge was demolished. This methodology reduced the time of traffic impacts on the public, from nearly four years of intermittent lane restriction...