Study on seismic design method of high-rise structures resistant to rare earthquakes on basis of progressive seismic failure mode

Aiming at the problem that the local concentrated damage of high-rise structures under rare earthquakes are easy to lead to structural overall collapse, and the essence of structural seismic failure with concentrated and insufficient consumption of static indeterminate times, this paper determines a multi-stage plastic development path with classified alternating gradual yield of members and fully consuming statically indeterminate times of energy dissipation members in batches for high-rise structures, and the progressive seismic failure mode of high-rise structure is proposed, which is characterized by controllable failure direction, extended failure path of structure, full plastic development.Considering the reciprocating characteristics of earthquake action, the influence of high-order vibration modes and the redistribution of nonlinear internal forces in the process during the multi-stage plastic development of structure, a standard earthquake action based on multi-stage mode combination is established, the quantitative requirements for seismic performance of multi-stage plastic development are given, and the seismic design of high-rise structures against rare earthquakes based on progressive seismic failure mode is proposed, which improves the energy dissipation capacity and nonlinear resistance of structures. In this method, the complex design of the high-rise structure based on the whole process of progressive seismic failure mode is simplified to the piecewise seismic design in the finite plastic stage, which solves the difficult problem of quantitative seismic design of the high-rise structure against rare earthquakes. To verify the effectiveness of this proposed seismic design method, a 10-story high-rise structure against rare earthquakes was designed by the proposed seismic design method. The achievements of structural progressive seismic failure mode and the seismic performance goal were verified by the nonlinear time history analysis method. The seismic performance of the structure designed by the proposed seismic design method and the structure designed by current codes were compared and analyzed. The energy dissipation capacity of the structure designed by the proposed seismic design method is increased by 57% under the action of seismic peak acceleration of 0.22g, and the maximum nonlinear resistance (base shear) is increased by 15.59% under the action of nonlinear static pushover.