Effect Of Residual Displacement On Damage Accumulation Of RC Frame Structure Based On Improved Ebrahimian Damage Model

Seismic data of previous generations show that after the main shock,one or more aftershock sequences of different intensities often occur.After experiencing an earthquake,the materials and components of the structure will be destroyed;at this time,after another earthquake,the structure will The damage was further aggravated,and eventually collapsed,resulting in serious casualties and economic losses.The residual displacement of the building structure is one of the important reference indicators to judge the degree of damage.When the residual displacement is larger,the maintenance difficulty and expenditure of the structure are higher,and when the residual displacement reaches a certain limit,the structure is lost.The significance of the repair.In this paper,based on the ordinary reinforced concrete frame structure,the improved Ebrahimian damage model is used to calculate and analyze the damage accumulation of the structure,and the effect of the residual interlayer displacement angle on the damage accumulation of the structure is studied,The main research content has the following three points:(1)The formula of the Ebrahimian damage model and the required demand parameters are introduced in detail,and the advantages and disadvantages of the damage index model are elaborated in detail.It has the advantages of small calculation amount and few demand engineering parameters;And it is not clear how the residual interlayer displacement affects the accuracy of the calculation results.Several other widely used damage models are introduced,including Park-Ang damage model,improved Park-Ang damage model,Wang Dongsheng model,Ou Jinping model,Niu Ditao model.(2)An ordinary six-story,three-span RC frame structure that meets the current building structure design specifications is designed on the PKPM design software,based on Opensees software for modeling and nonlinear time history analysis.The Ebrahimian damage index model was used to calculate the damage of the structure under an epicenter,an epicenter,epicenter and epicenter,epicenter and epicenter,epicenter and epicenter,epicenter and epicenter.The maximum and minimum residual interlayer displacement angles are used as the required parameters of the Ebrahimian damage model,respectively,and compared with the calculation results of the improved Park-Ang damage index model.The research shows that when the residual interlayer displacement is small,the influence on the calculation result of the Ebrahimian damage model is small,and as the residual interlayer displacement increases,the influence on the calculation result will also increase;when the maximum residual interlayer displacement angle is taken,the Ebrahimian damage The calculation results of the model are closer to the improved Park-Ang damage model under the six working conditions,indicating that the residual displacement in the Ebrahimian damage model should take the maximum residual interlayer displacement angle.(3)Based on the improved Ebrahimian damage model,the effect of residual interlayer displacement on structural damage accumulation was studied.Aiming at the three operating conditions of epicenter,epicenter,epicenter and epicenter,the effects of residual interlayer displacement angle on structural damage accumulation are studied.Studies have shown that: when the maximum residual displacement angle is less than 0.01%,the impact on the seismic performance of the structure is small;when the maximum residual displacement angle is greater than 0.01%,the seismic performance of the structure under two earthquakes will have a greater impact In particular,the damage of the existing residual displacement structure increased by 84.48% compared with the intact structure after experiencing the earthquake-large earthquake.