SEISMIC RETROFIT AND REHABILITATION OF THE KING GEORGEHIGHWAY COLEBROOK ROAD/BC RAIL OVERPASS

摘要

The Colebrook Road Overpass on King George Highway was constructed by British Columbia's Ministryof Transportation (MoT) in 1974. As a result of the provincial government's devolution of infrastructureto local governments, the overpass recently became part of the City of Surrey's bridge inventory. Thebridge is now 30 years old. With a remaining life expectancy of at least 20 years, and likely much longer,with timely completion of maintenance work. At this time, however, the structure is exhibiting clear signsof accelerated concrete deterioration resulting from elevated chloride ion (salt) concentrations in the deck,deck joints, and concrete components below.In 1991, this structure was identified by the MoT as being among the highest group of bridges requiringseismic retrofitting.To determine the appropriate level of seismic retrofitting, a seismic analysis and assessment of theseismic response has been completed for this structure. In order to maintain the capital investment, theCity has chosen to proceed with the proposed work plan which encompasses both a rehabilitation andseismic retrofit.