Research On Improvement Of High-rise Building Finite Element Analysis Software's Main Issues

With the continuous development of structures, structural analysis becomes increasingly complex. Facing the huge amount of computation, high efficiency design requirements, the research of high-performance structure finite element analysis software(SFEAS) is increasingly important.In this paper, several key issues of SFEAS are systematicly studied and some practical improvements are given, parts of them have been applied to the software develop.The major research are as follows:1) Research on the history and progress of finite element analysis software development.The features of today's domestic and international mainstream analysis and design software are summed up.After reading the relevant literature, the problems encountered with structural finite element analysis are summarized, and the detailed commentary is made.2) Research on the evaluation index of mesh quality.After the analysis and summary of the single evaluation index of the commercial finite element software ANSYS and SAP2000, a new evaluation index, which could be used by both the single grid evaluation and multi-grid finite element model, is recommended, The results show that the evaluation index is efficient and reliable.3) Research on the finite element solution way of wall-beam connection.With the penalty function method, after the constraint relation between the independent rotation field interpolation and the deviatoric strain tensor part of displacement field was established, a high-precision membrane with drilling-dof was constructed.4)Using the user programming featrures(UPFs) interface of ANSYS, the membrane was implanted. The results show that it can pass most of patch test with no extra zero energy mode.A variety of patch tests show it is a reliable, superior element.In addition, it has a simple data preparation and penalty parameter has a reasonable definition.5)Research on the finite element solution way to connect eccentric components.Through numerical experiments, the "eccentric rigid domain", which based on the master-slave constraint,was proposed. Regardless of component length, thickness, it can accurately calculate the displacement and force, which avoids the wrong results by the "rigid" bars method because the internal forces is dependent on the stiffness of the "rigid" bars.6) Research on the finite element error estimation methods.To improve accuracy,with the use of dichotomy and adaptive mesh method, the energy error estimation method is applied to the accuracy of evaluation of the simply supported beams, door-shaped structure calculation. The result shows when the energy error is less than 10%,the displacement and internal force will stabilize. In order to solve the stress concentration,a small regeion near the hole conner is excluded from the adaptive analysis domain,by which can extends the adaptive method to the analysis of high-rise building. When the calculation capabiltiy is limited,in order to get higher acurrancy,a refined mesh is proposed to use in the connect wall-beams.In summary, the paper has studied some key issues of sturcture finite element analysis which focus on the efficiency and accuracy problems. Some suggustions are given, which may promote the efficient and reliable structural finite element analysis software.