A Study on the Construction Techniques of an Open Cut Tunnel Annexed to an Existing Electric Railway While Assuring Safe Traffic

Abstract

In order to resist the landslides at the Chongqing-Huaihua Railway, A new 82m long open cut tunnel is constructed under normal operation of the railway, in spite of the HV contact wire overhead and tracks below the line. The tracks are reinforced by suspending every other track panel, so that construction of the open cut tunnel foundation under the ballast bed can be executed without affecting safe operation of the railway; arch-shaped steel pipe supports are used to decrease the interchange of HV contact wire during the construction without affecting normal operation of the railway; arch lining trolley is created to lift, slide and be electricity-proof, so that the work above the contact wire would not contact with the wire, and construction of arch ring and changing formwork would not be obstructed by normal operation. These new and creative schemes and techniques may provide approaches to constructing open cut tunnels for electric railways.