Study On The Influence Of Prestressed Cable On The Mechanical Characteristics Of The Joint Of Immersed Pipe Section

In recent years,with the rapid development of China’s economy,the demand for transportation in all walks of life is increasing.In this context,China’s transportation industry has made rapid development,in which the immersed tunnel method is also constantly used in the actual project.The difference between the construction method of immersed tunnel and other tunnels mainly lies in the structural stress and engineering construction.The joint of immersed tunnel is the weak link in the whole structure,so the bearing capacity and failure characteristics of the joint are very important to the safety performance of the whole immersed tunnel.Based on the National Natural Science Foundation Project "Research on mechanical properties of semi-rigid pipe joint in immersed tunnel"(Project No.: 51708368)and Hebei Natural Science Foundation Project "Research on Mechanism of joint performance degradation under differential settlement of integrated immersed tunnel"(Project No.: e2018210145),this paper adopts numerical simulation to solve the problem of joint degradation of immersed tunnel With the method of model test,the related problems are studied.First of all,through the actual engineering load situation of the immersed tunnel,the stress condition of the immersed tunnel is analyzed.After comprehensive consideration of all factors,the bending shear deformation and direct shear deformation of the joint of immersed tunnel are determined as the main research conditions of this paper.Secondly,the solid model of immersed tube tunnel is established by ANSYS.In the model,the joint contact problem is considered,the contact element is established,and the nonlinear rod element is established to simulate the rubber cushion.Because this paper mainly studies the joint of immersed tunnel,a more precise finite element model is established to ensure the accuracy of the calculation results.Finally,based on the three-dimensional finite element calculation results,the physical model test of immersed tunnel is carried out.The scale of immersed tunnel model is 1:10,which simplifies the section of immersed tunnel model.According to the experiment of similar material proportion,the proportion of similar material is determined,the experiment platform is rebuilt,the experiment scheme is designed,the reasonable lifting and docking methods are selected,and the test data are analyzed.The bearing capacity and failure characteristics of semi-rigid segment joints are obtained,which can provide reference for further study of immersed tunnel.