Non-linear Finite Element Simulative Analysis Of Frame-shear Wall Structures Based On Stiffness Degradation

With the social and economic development, our standards of living and aesthetic needs have been greatly changed and enhanced. Some traditionally and regularly designed buildings have been gradually out of our sight, replaced by those designed with novelty and specialty. It is well known that structural design specifications required a building to be planned as regular and symmetrical as possible. However, the regularity and symmetry in construction structure can no longer satisfy people's aesthetic demands with the rapid development in the architecture industry. On the contrary, irregular plate structure attracts more and more people's attention. Yet irregular plane structure can also cause a series of problems such as the mismatch of mass center and stiffness center, the aggrandizement of torsional effect which are caused by different kinds of stiffness degradation speed on different kinds of structure.This research is intended to carry on the nonlinear finite element analysis on the frame-shear wall structure which is the most common in high-rise construction. This analysis is largely dependent on the software ANSYS and done as follows.Firstly, finite element analysis was carried on concrete frame and shear wall under a sustained load respectively. Based on the variations in the load-displacement curve, it was found that the ANSYS simulation results neatly dovetail with the engineering test, and the stiffness degradation curves of both frame and shear wall was also got.Secondly, a two-floor concrete frame-shear wall with two spans was designed. By changing the thickness of the wall and the relative positions of the mass center and stiffness center, the researchers got the pressure capacity and mechanism of all the components under the circumstance of stiffness degradation; and then research was continued to figure out changes in the stiffness degradation curve stages, in the relative position of mass center and stiffness center, in torsional effect and in the effect of load-displacement curves, during the elastic-plastic stage. Through comparative analysis, the best structural arrangement to sustain the horizontal force was reached.The last step was to strengthen the weak parts of the shear wall, so as to enhance the bearing capacity and torsional capacity, and provide a guide to engineering design.