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GEORGE MASSEY TUNNEL
Location:Vancouver, BC, Canada Description:George Massey Tunnel, opened to traffic in 1958, carries two lanes of traffic each way under the Fraser River near Vancouver, Canada. The 629 m (2064 ft.) long immersed tunnel comprises six precast units, each approximately 105 m (345 ft.) long, which were floated into position and sunk into a trench in the loose sand of the river bed. Two ventilation buildings, one at each end of the immersed tunnel, house the main fans. The approach structures consist of reinforced concrete retaining walls, which are about 350 m (1148 ft.) long on each side of the ventilation buildings. The tunnel, which was designed with little consideration of seismic response, is located in an area of seismic hazard and is underlain by estuarine sediments about 600 m (1969 ft.) deep over bedrock. Owner and Client:Government of British Columbia Scope of Work:Buckland & Taylor Ltd. was retained, in 1999, to prepare a seismic assessment of the structure, to identify its seismic vulnerabilities and to establish feasible seismic retrofits and costs. This work was completed by March 2001. In May 2001, Buckland & Taylor Ltd. was selected to prepare the final design for the Seismic Safety Retrofit. Subsequently, MoT decided to upgrade the pumping and emergency power system and Buckland & Taylor Ltd. performed this work. The structural retrofit construction was completed in 2006. The plan at that time was to start ground improvement during the following years. However, upon completion of the structural retrofit, MoT decided not to proceed with the ground improvement (based on a second value engineering exercise taking into consideration a new plan of replacing the tunnel with a new crossing in the next 20 years). For more information on our bridge engineering services, please Contact Us. |
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