Numerical Simulation of on Mechanical Properties of New Precast Inverted Arch Joint in Highway Tunnel

In order to improve the engineering quality of highway tunnel, accelerate the construction speed, reduce the material consumption and construction cost, and improve the construction environment, this study proposed an optimized precast inverted arch form. ABAQUS was used to establish the three-dimensional finite element model of the precast inverted arch reinforced concrete structure. Considering the influence of different strength grades of bolts, bolt preload, bearing load and steel bars, the mechanical properties of the optimized precast inverted arch structure joints of highway tunnel were analyzed. The results show that the bolt prestress can effectively increase the capacity of the joint to bear positive bending moment. Under large load, the higher the bolt grade, the greater the maximum stress and the smaller the maximum strain; under this precast inverted arch structure, the vulnerable parts of the lower bolt are the connection between the screw and the nut, the vulnerable parts of the upper bolt are the screw, and the vulnerable parts of the concrete joint are the joint and the structural corner. The results have guiding significance for ensuring the safe construction of new prefabricated inverted arch of highway tunnel.