In recent years, the California Department of Transportation (CALTRANS) has developed innovative precast concrete connection systems for application in high seismic regions, including the San Mateo Hayward Bridge site. The award-winning San Mateo Hayward Bridge Widening Project is a 4.9 mile (7.9 km) twinning of an existing 30-year-old bridge in an active seismic area and over the environmentally sensitive San Francisco Bay. The only viable solution was an all-precast concrete substructure and superstructure consisting of driven cylinder piles, bent cap shells, bulb-tee girders, and stay-in-place deck panels. A 125-year service life was ensured through the use of epoxy-coated reinforcement, a high-pozzolan concrete mixture, and an extensive polyurea coating. Bridge construction advanced without falsework and within the existing right-of-way on a temporary work trestle. This article describes the design, production, and erection challenges, as well as the decisive advantages of precast concrete construction in environmentally sensitive and earthquake-prone regions.
