Study On Seismic Performance Of Prefabricated Outerbuilding Envelop Enclosure

Green energy and residential industrialization has become the major trend of the housing industry development in China. With the study of new building materials, prefabricated outerbuilding envelope wall panels gradually replace the traditional brick masonry. Through experimental and theoretical research on the seismic performance of the prefabricated outerbuilding envelop enclosure, the failure mechanism and bearing capacity of the structure under earthquake were studied in this paper. The influences on seismic performance of different factors such as wall panel types, connection forms, soft filling, window and door openings, wall panel thickness, ect, are discussed in detail. Some suggestions on design methods and practical construction measures for improving the seismic performance of the prefabricated outerbuilding envelop enclosure are given, which provides a theoretical basis for the seismic design of the structure.Considering the influence of different factors, the quasi-static loading experiment on 8 different structural form specimens is carried out. Throngh the analyses of experimental phenomenon, the failure mode and the measured data, the influences of different factors on the seismic performance of the structure are analyzed. Then the numerical simulation analysis of the structure is carried out using the ANSYS finite element software. Finally, based on the numerical analysis results, the simplified mechanical model of the prefabricated outerbuilding envelop enclosure is proposed. The results are as follows:(1) By quasi-static loading test, it is concluded that the whole working performance of the prefabricated outerbuilding envelop enclosure behaves well, the deformation of the steel connecting piece is small and the wall panels are not falling out, but the mortar crackes early in some local locations of the structure. The failure mode of the structure is that the wall panels are destructed partially at first and then the whole structure is destroyed.(2) Based on the study of the failure mode, skeleton curve, hysteresis curve, ductility, degradation effect, energy dissipation factor of the structure, it is find that the damage of lightweight wall panel is relatively serious, but larger stiffness and stronger energy dissipation ability compared with the composite wall panel, the seismic performance of different connection forms are similar, soft filling materials and door and window openings have a certain effect on the seismic performance, two wall panels specimen has a good seismic performance and the stiffness and energy dissipation capacity are both improved.(3) Taking into account the contact between the various components, the microscopic discrete model of the prefabricated outerbuilding envelop enclosure is established using the ANSYS finite element software. Different element types and material nonlinear constitutive model of concrete, reinforcing steel bar, wall panels and the connecting pieces are selected respectively. The obtained numerical simulation results are in good agreement with the experimental results. The numerical simulation analysis of the force mechanism, the internal force transfer path and the ultimate failure mode of the prefabricated outerbuilding envelop enclosure provide a theoretical basis for the simplified mechanical calculation model of seismic resistance of the prefabricated outerbuilding envelop enclosure.(4) Based on the finite element numerical simulation results, a simplified model for the mechanical calculation of seismic resistance is presented. The practical calculation formula of ultimate bearing capacity of seismic resistance is derived from two parts of frame and wall panels, covering the elastic modulus, the thickness and the number of the wall panels, which is convenient for the practical engineering application.