Application Of Contact Element In Plate-cone Reticulated Shell Structure

The plate-cone reticulated shell structure is a kind of structure that the cone formed by thin plate is placed along the surface of the reticulated shell,and the top of the cone is connected by metal skeleton to form the shell.At present,the analysis of the mechanical performance of the plate-cone reticulated shell is carried out by using the complete coordinated model,which neglects the contact between the plate and the plate.In this paper,the contact problem is introduced into the structure of the plate-cone reticulated shell to study the application of the contact element in the plate-cone reticulated shell structure.In the contact model establishment,using the ANSYS,according to the geometric relationship to compile the corresponding program,can automatically build the plate-cone reticulated shell structure contact model,for subsequent analysis.In a plate-cone reticulated shell structure,the cone and cone are connected at finite points by bolts and other connectors,while most of the area is in contact at non-connections.Therefore,this paper establishes the contact model,compares and analyzes the contact stiffness,initial gap and friction coefficient and observes the influence of these three factors on the static analysis of the plate-cone reticulated shell structure.It is concluded that the contact stiffness of the plate-cone cylindrical reticulated shell is 2E8N/m-2E15N/m and that of the plate-cone spherical reticulated shell is 2E8N/m-2E14N/m,which can guarantee theaccuracy and efficiency of calculation simultaneously.The initial gap has a great effect on the web stress,and has little effect on the axial force and the deflection of the joint.The effect of friction coefficient on numerical results of structural static analysis is negligible.Ansys software is used to introduce the contact problem into the calculation model of plate-cone reticulated shell.Comparing the numerical calculation of contact model and complete coordination model,the function of contact unit in analysis is studied.It is concluded that for the static analysis,the difference between the two calculation models is large,so it is necessary to consider the contact problem in the research process.In addition,the natural vibration characteristics and response spectrum of the contact model and the complete coordination model are analyzed respectively.It is concluded that the natural frequency of the plate-cone reticulated shell structure is dense,and there is no obvious periodicity.The natural frequencies calculated by the contact model and the complete coordination model are almost the same,and the corresponding vibration modes are basically similar.The influence of the contact element on the numerical calculation of the natural vibration characteristics of the plate-cone reticulated shell structure can be ignored.The seismic displacement,member axial force and web equivalent stress calculated by the contact model are quite different from the corresponding values of the complete coordination model,so it is necessary to consider the influence of the contact element in the analysis process.