Study On Seismic Performance Of Bi-directional Self-centering Frame-rocking Wall Structure

Frame-rocking wall structure is one of the important research directions of earthquake resilience building.Its damage mode and seismic performance are easy to control,and the energy consumption of the structure can be fully utilized.However,due to the large mass of the rocking wall,residual deformation that is not easily recovered after the earthquake increases the difficulty and cost of structural repair.In order to reduce the residual deformation of the frame-rocking wall structure under earthquake and improve its seismic performance,this paper analyzes a self-centering frame-rocking wall structure,in which the post-tensioning tendons are set in the rocking wall to achieve the deformation recovery ability after the earthquake.The theoretical analysis and numerical simulation method are used to systematically analyze the mechanical principle of the self-centering framerocking wall structure?the seismic performance of the unidirectional structure and the seismic response of the bi-directional structure.The work and results include the following aspects:(1)Theoretical study of self-centering frame-rocking wall structure.The basic equations of the mild steel damper frame-rocking wall structure are derived.The calculation results and the scope of application of the basic equation are analyzed.The formula for equivalent damper stiffness of the equal-section mild steel damper is proposed.A parameter to measure the bending moment of the rocking wall is proposed—the equivalent prestressing stiffness.The effect of two equivalent stiffness on the structural deformation and force is analyzed.(2)Seismic performance of unidirectional self-centering frame-rocking wall structure.Through simulating the pseudo-static test in the literature,the seismic performance of unidirectional selfcentering frame-rocking wall structure is studied.The influence of tendons and dampers in the structure is analyzed,and the reasonable values of ratios of two equivalent stiffness are summarized.(3)Research on seismic response of bi-directional self-centering frame-rocking wall structure.The parameter-optimized unidirectional self-centering frame-rocking wall structure is arranged into the whole structure to form a bi-directional self-centering frame-rocking wall structure.Two sets of models with no eccentricity and unidirectional eccentricity are respectively established.Dynamic elastic-plastic time history analysis is carried out.The reaction law under the action of earthquake is studied,and the seismic performance of the bi-directional self-centering frame-rocking wall structure is compared and evaluated.The research shows that the bi-directional self-centering frame-rocking wall structure is superior in seismic performance when it is set to be eccentric and unidirectional.The research work of this paper provides a reference for the theoretical analysis and popularization of the self-centering frame-rocking wall structure.