Study On Seismic Performance Of Metal Damper With Restorable Functio Between Prefabricatead Exeterior Wall Panels

The prefabricated external wall panel is connected with the main body by flexible connections,and the bending moment at the bottom of the wall can be relaxed,which can able to avoid the damage of the wall under the earthquake.However,the integrity of prefabricated components is relatively weak compared with cast-in-place structure.If a good seismic design can not be carried out,it will cause serious harm when an earthquake occurs.Energy dissipation technology refers to the installation of energy dissipation devices in the structure to dissipate seismic energy through its plastic deformation such as bending,shearing or friction.Based on the previous research,a flexural energy dissipating metal damper for the functional recovery of prefabricated exterior wall panels is proposed The metal damper consumes energy through out of plane bending of T-shaped steel plate webs.It is applied to prefabricate and assemble four outer wall panels,and its theoretical analysis,experimental research and numerical simulation are carried out.The main contents of this paper are as follows:(1)Firstly,the development process and research results of prefabricated wall panels and metal dampers(bending and shear energy dissipation)are summarized,and the main research contents of this paper are put forward according to these situations;(2)In order to meet the requirement of "swing",the design principle of the functional recoverable metal damper is described.The metal damper can be obtained by cutting the existing model steel directly to avoid the weakening of the section performance caused by welding.The section of the damper is optimized and the ideal mechanical performance of the metal damper is proposed,;(3)Six groups of metal dampers installed between prefabricated exterior wall panels are tested under quasi-static cyclic loading.The hysteretic curve of the system,the hysteretic behavior,skeleton curve,strength degradation,strain history and energy consumption capacity of each group of metal dampers are analyzed.The energy consumption of metal dampers is discussed The influence of the thickness,length of T-shaped steel plate web,the connection between web and flange and the loading system on its performance;(4)According to the plastic curvature model and the strengthened constitutive curve,the strength estimation formula of metal damper is derived,and the correctness of the formula is verified by discussing the length of its plastic hinge and comparing the formula value with the experimental value;(5)Based on the finite element analysis of OPENSEES,the metal damper model is established,and the correctness of the damper OPENSEES model is verified by the comparison of the hysteretic performance;on this basis,the original structure is strengthened by setting the wallboard and metal damper,and the seismic response under 40 seismic waves verifies that the new structure improves the seismic capacity of the original structure.