Interaction of Pipe-Roof Reinforcement and Tunnel Construction under Existing Highway

Pipe-roof has been adopted extensively as pre-support in tunnel construction. The vertical deformations of the pipe-roofs in the entrance of Liuyanghe Tunnel are monitored by installation of a series of strain gauges to investigate the mechanical behavior of the pipe-roofs during the tunnel excavation. Based on the monitoring results, the mechanical characteristics and the evaluation of the reinforced effect of pipe-roof in the construction process were analyzed.