Numerical simulations of shallow-buried large-span tunnel had been performed in this study for tunnel excavation method selection among both-side heading method, three-bench temporary invert method and three-bench seven-step method. Stress and deformation of surrounding rock and safety of support structures had been analyzed for different methods during excavation process and the conclusions had been draw as following: (1) for the restrain effect of surrounding rock, both-side heading method is better than three-bench seven-step method and the three-bench temporary invert method is the worst; (2) comparing to both-side heading method, even though the deformation of three-bench method is larger, the stress in surrounding rock has been effectively released in this way so that the load acting on the supports will be relatively smaller. By using the pipe-roof early support technology in three-bench method, the safety of construction can be ensured and the construction period can be reduced; (3) for three-bench temporary invert method, since the excavation face is relatively big, the stability of working face is poor. In addition, the assembly and disassembly for temporary invert is time consuming with higher cost. For three-bench seven-step method, the surrounding rock deformation of tunnel cross-section is larger and the plastic range is wider, however, all are within the safe range and also the safety of the excavation face can be ensured by the core of soil reserved in this method. Hence, the three-bench seven-step method is a reasonable method because it can accelerate construction process and reduce cost, while ensure supporting structure safety and excavation face stability.

A non-linear 3D finite element model was established to simulate the three edge-bearing test of TRC reinforced concrete pipe. The pipe load-displacement curve, cracking load, and ultimate load simulation values are in good agreement with the test values. Subsequently, a parametric study was conducted. The effects of reinforcement layer bonding mode, mesh size of concrete element, mesh distribution rate and concrete compressive strength on the performance of reinforced concrete pipeline strengthened by TRC were considered. It provides a basis for the design of TRC reinforced concrete pipes.