Inspection and structural investigation was performed to determine the causes and to identify possible corrective measures for a progressive, 22-inch deflection on the main span of this bridge. The structure is a three-span, cast-in-place lightweight concrete, single-cell box girder structure with a center span of 640 ft and two side spans of 325 ft each. The superstructure was post-tensioned longitudinally, vertically and transversely. On-site inspections and laboratory tests were conducted to assess the properties of the lightweight concrete, followed by an extensive analysis using the SFRAME computer program which entailed modeling of the construction history, the bridge's behavior with respect to concrete properties including thermal expansion coefficient, unit weight, modulus of elasticity, shrinkage and creep. T.Y. Lin International (TYLI) was the structural consultant.

• Mark Ketchum, current OPAC principal, served as Supervising Engineer while at TYLI, and provided guidance on the analytical investigation and creep modeling which was performed using his SFRAME program.
• Kwong Cheng, current OPAC principal, served as Supervising Engineer while at TYLI, and provided guidance on the analytical investigation and load-testing of the bridge, and directed site inspection.