Finite Element Numerical Study Of Carbon Fiber Tube With Axial Compression

This paper used the carbon fiber composite material pipe under axial compression of a new type of cable dome structure as the object of study. The stability of the carbon fiber composite material tube under axial compression is analyzed by FEM.Firstly, according to the experimental results of related literature, using the carbon fiber tube under axial compression finite element model to make initial defect analysis. For the instability of the long tube, you can take the 1/160 length of the tube as the equivalent initial bending to describe the initial defect of the overall instability of the long tube. For the local buckling of the short tube, you can take 5/12～5/9 wall thickness of the tube as the initial defect.Then study the effect of ply angle and slenderness ratio on the bearing capacity of carbon fiber composite material pipe under axial pressure. When using [00]n laying way, the axial compression bearing capacity of the pipe is largest. When adding a small amount of 900 paving layer, the bearing capacity of the tube will be slightly reduced but the ductility increases greatly. The axial compression bearing capacity of the carbon fiber tube decreases with the increasing of slenderness ratio. The ductility of the tube increases with the increasing of slenderness ratio.In the end study the influence of the elastic support stiffness on the bearing capacity of carbon fiber composite material pipe under axial pressure. For the lateral displacement elastic supporting carbon fiber composite material pipe under axial pressure, bearing capacity first increases then decreases with the increase of lateral spring stiffness. For with and without lateral displacement elastic supporting carbon fiber composite material pipe under axial pressure, when the top and bottom of the spring hinge stiffness increasing, the stable bearing capacity increases, and the ductility of the CFRP tube under axial compression decreases. In practical application should take larger spring stiffness so that the axial compression CFRP tube is in no lateral elastic boundary conditions. At the same time in order to improve the bearing capacity and not to reduce ductility of CFRP tube, the top and the bottom of the spring hinge stiffness and the spring hinge stiffness ratio must ensure in an appropriate range.