Plane Grid Generation And Dynamic Response Analysis Based On A Structure Analysis Software SASS

Finite element method(FEM),which is a basic numerical method for structural analysis,has been widely used in various industries.The rationality of mesh generation and the selection of interpolation function are the important prerequisites for finite element analysis and calculation,to a great extent,the calculation accuracy of the model is determined.The approximate finite element solution of the model will be close to the exact solution if the mesh elements of the structure meet the convergence requirement.In order to ensure the calculation precision of the model and reduce the computing time cost,this paper proposes different mesh generation methods for different types of large elements based on the structure analysis software SASS,which combines the visual function of VB and the numerical computing capability of FORTRAN.For eight-node curved edge element,a method for judging the concave and convexity of planar curved polygon is presented.After linear judgment of curved edge,the displacement vector method combining node connection and displacement is used to generate finite element mesh.For the crack edge element,the mesh near the crack tip element is further refined by using the variable scale partition model,and the accuracy of calculation stress intensity factor at the crack tip is improved on the basis of ensuring that the number of the whole element is invariable.In this paper,a numerical analysis of a plane plate with a defect hole and a crack is carried out by using the method,and the calculation results show that the numerical solution obtained by using the method is very close to the theoretical solution,and the numerical solution obtained by the program still has a certain reference significance for some complex problems with no effective theoretical solution.In structural analysis,the damage caused by dynamic loads is much greater than that caused by static loads,such as earthquake,bridge beam collision and so on.On the basis of the structural analysis software SASS,a dynamic calculation module is developed in this paper,and the dynamic response of two-dimensional plane tunnel under impact load is calculated by Newmark method.The calculation results show that the self-developed structural analysis software used in this paper is reliable in algorithm,and the numerical results have some reference value for some complicated engineering practical models,and also provide an effective reference for theoretical research.