Central Avenue Bridge At Alameda County Flood Control Channel

The Central Avenue Bridge Project included the construction of a new 64 foot long clear span precast prestressed concrete voided slab bridge.  The structure spans over an environmentally sensitive channel operated by the Alameda County Flood Control District.  Precast construction was selected to limit environmental impacts that would have been caused by temporary falsework and construction equipment needed for cast-in-place construction located in the channel.   Improvements to the roadway adjacent to the bridge included the construction of a traffic circle.  Due to the proximity of the bridge to the proposed traffic circle, the bridge was required to have curved edges of the deck to match the geometry of the traffic circle.  This curved geometry was achieved with a custom-designed and fabricated triangular-shaped precast concrete element supported on two sides by the abutment and a ledge fabricated into an adjacent precast slab.  After much discussion between the Owner, Engineer, and precast subcontractor, and to ensure uniform bearing of the custom element on the ledge fabricated into the adjacent precast slab, the precast subcontractor fabricated the element using the “match-casting” technique.  The project included coordinating with the Alameda County Flood Control and Water Districts, the City of Newark, and PG&E.