Study On The Earth Pressure And Structural Internal Forces Of Fabricated Tunnel

Construct prefabrication has become an inevitable trend in the development of underground engineering design and construction technology. Fabricated tunnels have been extensively applied in domestic and overseas high-grade highway construction due to its reasonable load, lightweight structure, convenient construction, etc. The earth pressure is one of the main loads of tunnel structure. It is of great significance to study the earth pressure and tunnel internal force.The influence law of the earth pressure distribution mode in tunnel-soil interface is analyzed with PLAXIS, involving the effects of tunnel section shape, fill properties and fill depth, compacted load, structure stiffness, etc. Comparison analysis of the full-scale model experiment results and some common methods' is carried out, including the finite element method, standard method for highway and railway, Marston's theory and method proposed by institute of Geotechnical Engineering in ZheJiang University. The main features and their applicability are pointed out, which is an important basis for engineering design.By taking the application of fabricated tunnels in Sixu highway as a background, the internal force of tunnel structure is systemic analyzed based on soil-structure interaction. Optimization suggestions are also raised for the design of underground structure system.