US Route 1 at Ft. Belvoir

This design-build project consists of the widening of a 3.68 mile segment of U.S. Route 1 (Richmond Highway) from Telegraph Road (Route 611) to Mount Vernon Highway (Route 235) in Fairfax County, VA from four through lanes to six through lanes, as well as the construction of new bridges over the Accotink Creek. These improvements are necessary to improve traffic operations on Route 1 and access to a new Army Hospital located on Fort Belvoir.

ALA provided all structural engineering and design for the NB and SB replacement bridges on Route 1 over Accotink Creek. The proposed dual bridges replace an existing 65 feet two span concrete bridge and have integral backwalls with a total span of 270 feet. The NB and SB bridges have two spans supported on a center multi-column bent pier and semi-integral abutments. The abutments and the piers are founded on drilled shafts that are designed for a 100-year scour and checked for 500-year scour. The drilled shafts were sized to withstand up to 30 feet of unsupported length during an extreme event of scour. The roadway profile and bridge spans were set to provide a minimum of 12” free board during a 100-year storm event.

ALA prepared the structural design and construction plans for the bridges in three months to allow for the start of construction in Spring 2014. ALA also provided construction services.