高速公路隧道装配式仰拱接头力学性能研究

为研究公路隧道装配式仰拱结构接头的力学性能，首先建立装配式仰拱接头三维数值计算模型，模拟接头细部结构，分析比较弯螺栓、直螺栓对仰拱接头在不同轴力、弯矩组合作用下接头张开量、转角、螺栓应力以及接触压应力等的变化规律。然后采用大比例尺室内仰拱接头加载试验对模拟结果进行验证。结果表明：接头张开量、转角随着弯矩增加不断增大，接头抗弯刚度不断降低；接头张开量、转角随轴力增加而减小，接头抗弯刚度则不断增大；弯螺栓接头抗弯刚度大于直螺栓接头抗弯刚度；螺栓整体受拉，螺杆受力状态与螺栓形式及接头变形有关，整体上弯螺栓应力大于直螺栓应力。对比分析数值和试验结果，整体变化趋势一致。研究成果为公路隧道装配式仰拱接头设计提供参考。

Study on Mechanical Properties of Drill-and-blast Highway Tunnel Fabricated Inverted Arch Joint

In order to study the mechanical properties of the joint of the prefabricated inverted arch structure in highway tunnel, firstly, a three-dimensional numerical calculation model of the prefabricated inverted arch joint is established and the detailed structure of the joint is simulated. Analyse and compare the change rule of joint opening, rotation angle, bolt stress and contact pressure stress of bending bolt and straight bolt to inverted arch joint under different axial force and bending moment combinations. Then, the simulation results are verified by large-scale indoor inverted arch joint test. The results show that the joint opening amount and turning angle increase with the increase of bending moment, and the bending stiffness of the joint decreases. The joint opening and turning angle decrease with the increase of axial force, and the bending stiffness of the joint continues to increase; The bending stiffness of bent bolt joints is greater than that of straight bolt joints. The overall tension of the bolt, the screw stress state is related to the bolt form and joint deformation, and the overall bent bolt stress is greater than the straight bolt stress. Comparing and analysing the numerical and test results, the overall change trend is consistent. The research results provide a reference for the design of prefabricated inverted arch joints for highway tunnels.