Design of Steel Pipe Final Lining Subjected to Large,Seismically Induced Axial Strains

摘要

The Port Mann Main Water Supply Tunnel is a 1,000-m (3,280-ft) long two-pass tunnel. Therntunnel is approximately 3.5-m (11.5-ft) in excavated diameter, and is sized to receive a 2.13-m (7.0-ft) ODrnpipeline as the final liner. The tunnel will be excavated by TBM between two shafts on either side of the FraserrnRiver, British Columbia, Canada. The tunnel has precast segments as initial lining and steel pipe as final lining.rnIt is located in an active seismic region, having a design earthquake with a 10,000-year return period and PGArnof 0.7g. Axial strains of up to 0.4% are anticipated because of seismically induced lateral spreading. This paperrndiscusses seismic design for the final lining to achieve the owner’s seismic performance objectives.