Bridge Name: Soto Street Over Los Angeles River Location: Los Angeles, California Description: The Soto Street Bridge is a concrete arch structure constructed in 1928 to cross the Los Angeles River in the city of Vernon. It consists of six spans of six rows of reinforced concrete girders, spandrel columns and arch ribs, topped with an RC deck. The arch ribs are stiffened transversely by spandrel beams and umbrella stiffeners. Transverse beams also stiffen the deck. The arch ribs frame into north and south abutments and piers originally numbered one through five. The original piers sit on footings supported by timber piles. In 1987 the bridge was widened on both sides with CIP/RC slab on top of PC/PS concrete girders supported by RC pier walls. The pier walls of the widening structures sit on new footings supported by steel H-piles. New abutments were built before and after the abutments of the original arch structure and the piers were renumbered Pier 3 through Pier 7. RETROFIT STRATEGY The primary goal of the retrofit concept is to limit the rotation of the arch structure piers. This is accomplished by connecting the arch structure and widening structure piers together and allowing the widening structures, with their more modern details, to take the majority of the seismic forces. The widening structure piers and footings are strengthened to cope with the additional seismic demands, and the vulnerable components of the arch structure are retrofitted to enhance their flexural and shear capacities. The following is a brief description of the retrofit measures: Corbel: A corbel is added around Pier 3 through Pier 7 to provide a solid connection between the arch and widening piers. This results in the widening structures taking much of the seismic forces. Widening Pier Strengthening: The lower portions of the widening piers are strengthened by adding solid reinforced concrete in place of the fascia shells. The new detailing provides the piers with sufficient strength and ductility to withstand the increased seismic demands. New Piles: Steel pipe piles are added to the enlarged widening footings to cope with the additional seismic force from the combined structure. Arch Rib Strengthening: Reinforced concrete bolsters are added around the ends of the arch ribs to prevent possible shear and flexural failures. Infill Walls: Longitudinal and Transverse infill walls are cast between the arch bridge spandrel columns to lower demands in displacements and forces in the combined structures. Scope: Independent check of retrofit strategy and contract plans Cost: $1,000,000 (approx.) Owner: County of Los Angeles Reference: Mr. Nadeer Tamannaie CH2M Hill 2485 Natomas Park Drive, Ste 600 Sacramento, CA (916) 920-0300 End Date: 1996

Project Categories Bridge Design Seismic Bridge Design Bridge Construction NBIS Bridge Inspection Bridge Design Experience Bridge Construction Experience