Structures / Alvord Lake Bridge
- Ernest L. Ransome
The Alvord Lake Bridge is the first reinforced concrete bridge that was built in the United States. Ernest L. Ransome employed his patent for twisted square steel reinforcement bars to provide a robust structure with enhanced flexural strength. The bridge survived the 1906 earthquake and fire with minimal damage, demonstrating the viability of reinforced concrete as a durable building material compared to many of the wood-framed structures in San Francisco that were destroyed.
The Alvord Lake Bridge is a reinforced concrete bridge located in Golden Gate Park with a 64-foot width and 29-foot span. The architectural features consist of reliefs to create a sandstone-like exterior and concrete derived deposits resembling stalactites that cover the passageway under the arch bridge. Portions of the abutment walls have developed large cracks and permanent displacements due to the lateral earth pressures and tree roots. The bridge and abutment walls have been repaired by the firm Giampolini Courtney.
- ASCE National Civil Engineering Landmark (1970)
- The structure is the oldest reinforced concrete bridge in the United States