Evaluation Of Post-earthquake Function Restoration Capacity Of Reinforced Concrete Frame Structured Buildings Considering Damage Of Non-structural Components

With the process of urbanization,the effect of the great earthquake on the built environment and economic activity becomes more serious.People are no longer satisfied with the performance level of the life safety for buildings under the earthquake.They expect that buildings can restore their functions in a relatively short period to provide the necessary service capabilities.That is to say,buildings should have good post-earthquake function restoration capacity to minimize the casualties and economic losses caused by the earthquake and the impact of the earthquake on the post-disaster recovery process.The functions of buildings are not only related to the structural components,but also related to the non-structural components.In this paper,reinforced concrete(RC)frame structured buildings were taken as case study,and adding viscous dampers and adding base isolation bearings were adopted to improve the post-earthquake function restoration capacity of RC frame structured buildings.The Performance-Based Earthquake Engineering(PBEE)framework methodology was used to investigate the post-earthquake function restoration capacity of RC frame structured building and the corresponding energy-dissipated building with viscous dampers and base-isolated building.And both the damage of structural components and the damage of nonstructural components were considered.The main research work is as follows:(1)The finite element model of the structure was established by OpenSees software,and the elastic time history analysis was carried out.It is shown that the seismic capacity of the RC frame structure can be effectively improved by adding viscous dampers and installing base isolation bearings.(2)Based on the results of Incremental Dynamic Analysis(IDA),multidimensional seismic demand analysis and seismic vulnerability analysis of the RC frame structure and the corresponding energy-dissipated structure with viscous dampers and base-isolated structure were carried out.The results show that the correlation coefficient between structural response variables varies along the height of the structure.Under the given earthquake intensity,when considering the damage of non-structural components,the probability of the damage exceedance increases obviously.The influence of correlation between threshold variables on seismic vulnerability decreases with the improvement of performance level.In addition,the overall seismic vulnerability curves of energy-dissipated building and base-isolated building are significantly shifted to the right comparing with RC frame structured building.Therefore,the failure probability of RC frame structured building is significantly reduced by adding viscous dampers or by adding base isolation bearings.(3)Considering the impact of depreciation of building function,the loss ratio was taken as an index to investigate the loss of building function quantitatively based on the results of multi-dimensional seismic vulnerability analysis.The results show that the function loss of RC frame structured building is reduced by 10.9%,7.6% and 10.6% respectively under frequent,moderate and rare earthquakes by adding viscous dampers.And it is reduced by 26.7%,36.2% and 44.2% respectively under frequent,moderate and rare earthquakes by adding base isolation bearings.Comparison of the results indicate that adding base isolation bearings is more effective to reduce the loss of building function.(4)Based on the multi-dimensional seismic vulnerability analysis results,the post-earthquake restoration time of RC frame structured building and the corresponding energy-dissipated building and base-isolated building was quantified,and the post-earthquake function restoration capacity was investigated by combining the analytical results of function loss.The results show that under frequent and moderate earthquakes,the effect of adding viscous dampers and adding base isolation bearings on improving the post-earthquake function restoration capacity of RC frame structured building is not obvious.But under rare earthquake,the effect is obvious to increase the post-earthquake function restoration capacity by 8.31% and 30.07% with adding viscous dampers and adding base isolation bearings respectively.In addition,the difference of post-earthquake function restoration capacity of RC frame structured building and the corresponding energy-dissipated building and base-isolated building is not obvious when the PGA of earthquake is not larger than 0.2g.With the increase of the earthquake intensity,the difference becomes larger.It is found that it is necessary to account for the influence of non-structural component damage for evaluating post-earthquake function restoration capacity of buildings.For RC frame structured building,adding viscous dampers or adding base isolation bearings can improve the post-earthquake function restoration capacity,and the effect of adding base isolation bearings is more obvious.