Study on Section Repair Method for Cut and Cover Tunnels
Tokyo Metro currently maintains 196km of structures with 9 routes, of which approximately 85% are tunnels. As a daily repair against deformation such as freaks and leakage of tunnels, cross-section repair is commonly used. However, methods and materials of crosssection repair have been used for many years without being updated. So, to introduce a method using the latest technology and materials, we established an evaluation method for new adoption. First, we have invented tests to determine required performance of cross-section repair materials and carry out performance checks. It is a laboratory test conducted using specimens imitating actual tunnels and a field test conducted by actual tunnels. Next, based on the knowledge in these tests, a flow was developed to investigate whether to adopt new technology and materials. From the above, it was possible to establish an evaluation method of the tunnel cross-section repair method and to introduce new technology smoothly.