Seismic Collapse Capacity Spectra And Collapse Displacement Response Spectra

Earthquake is a kind of geological disaster caused by the greatest damage to human society in all natural disasters on earth. Once a strong earthquake comes, preventing the collapse of building structure is the most effective way to avoid the serious human casualties. In this paper, the collapse capacity and collapse displacement response of a single degree of freedom system are calculated based on the incremental dynamic analysis method. The influence factors of the structural collapse and collapse displacement response are studied. Many scholars have carried out the research on the structural collapse of various concrete structures, but the research on the structure collapse capacity spectra and the structure collapse displacement response spectra is not much. At the same time, the structural seismic design codes of many countries are only for considering single ‘design earthquake’, and have not considered the effect of aftershocks.The purpose of this paper is to provide a reference for the seismic design method based on collapse. We have studied ground motion and the structure itself, which affect the structure collapse capacity and structure collapse displacement response. Specific research contents are as follows:(1) Structural collapse capacity spectra method is introduced, and put forward the structural collapse displacement response spectra, selected a large number of ground motion records on different site conditions, calculate the corresponding structural collapse capacity spectra and collapse displacement response spectra, and found that structural collapse capacity spectra of soft soil ground was significantly lower than that in other site conditions, also found structure collapse capacity spectra and collapse displacement response spectra of near-field records set are obviously different.(2) Calculated the collapse capacity spectra and the collapse displacement response spectra of different structural parameters. Study found that structural damping and the P-delta effect of structure has significant influence on its collapse capacity spectra, but not on the displacement response spectra. At the same time, hysteretic model parameters of the structure was studied, different structural parameters have different effects on the collapse capacity spectra and the displacement response spectra of the structure. And it was found that the change of the shrinkage effect in the strain direction and the change of the unloading stiffness had no effect on the structure’s collapse response spectra. In order to facilitate the engineering application, the regression analysis is also given.(3) The structure collapse capacity spectra and collapse displacement response spectra of the mainshock-aftershock sequence-type ground motions was studied. Also structure collapse and collapse displacement response of different structure parameters were calculated, and a comparative study is made on the collapse capacity and the displacement response of the structure without considering the effects of aftershocks.