Mr. Tamannaie served as the Project Manager for the County's On-call Bridge Seismic Retrofit Program, funded through the HBRR program. The firm was assigned three bridges, all crossing over important waterways.
The No-Collapse criteria was applied in determining the seismic retrofit of the structures. Innovative retrofit strategies and design alternatives were selected in such a way that environmental and right-of-way impacts were eliminated or minimized.
Soto Street over Los Angeles River: A six-span arch bridge constructed in 1928 and supported on large, unreinforced pier walls and timber piles. It was retrofitted by strengthening the arch rib ends, placement of transverse and longitudinal web walls between the spandrel columns on the ribs,
tying of the original and widening pier walls together, addition of shear keys and foundation enlargement.
Westminster Avenue over Haynes Steam Plant Channel: A four-span precast, prestressed girder structure constructed in 1964 and supported on pile extension bents. The bridge was retrofitted by tying the superstructure spans together at each bent,
load transfer to the abutments and providing additional seismic resistance at the abutments through anchor slabs attached to large diameter pile shafts.
Second Street Bridge over Alamitos Bay: A seven-span, cast-in-place, concrete T-beam structure built in 1966. Retrofit design was developed to tie the superstructure spans together at each bent, transfer the load to the abutments and provide additional
seismic resistance at the abutments through a strutting frame and a cluster of large diameter pile shafts at each abutment corner. The project presented the challenge of the presence of a large pump station at one end of the bridge and assuring its integrity during the seismic movements of the bridge.