采用城市动力弹塑性分析方法预测唐山市区建筑震害

Building seismic damage prediction of Tangshan City based on the nonlinear time-history analysis of urban buildings

城市区域建筑震害预测是城市防震减灾工作的重要决策基础。为实现更加合理、细致、直观的城市区域震害预测,本文采用了城市动力弹塑性时程分析方法预测了唐山市23万多栋建筑的震害。分别采用多自由度剪切模型和弯剪耦合模型快速建立中低层和高层建筑的分析模型,给出了每栋建筑不同楼层的震害结果以及震害过程三维可视化展示,并且对比了3种地震动衰减关系的预测结果,对最为合理的椭圆形衰减关系的结果进行了详细的分析。结果表明唐山市当前建筑抗倒塌能力相比1976年唐山大地震时有了显著提高,但非设防的老旧房屋依然破坏严重,城市抗震"韧性"有待提高。本文研究为大规模的城市区域建筑震害预测提供了重要方法和应用案例。

Urban regional seismic damage prediction provides decision-makers with important information to mitigate and prevent seismic disaster. In order to achieve more reasonable, detailed and intuitive seismic damage prediction of urban buildings, the nonlinear time-history analysis of urban buildings is adopted to perform seismic damage simulation for 230,683 buildings in central Tangshan City. Multi-degree of freedom （MDOF） shear model is used to establish analysis models of low and mid-rise buildings, and MODF flexural-shear model is adopted for the tall buildings. Different stories seismic damage of each building and 3 D visualization of buildings＇ seismic respon- ses are obtained. The prediction results of three different ground motion attenuation relationships are compared. Then the seismic damage simulation results with the most reasonable ellipsoid attenuation relationship are discussed in detail. The following conclusions can be drawn： （1）The building seismic resistance of Tangshan City has been remarkably improved over the past 4 decades ; （ 2 ） Old non-engineered buildings have very low seismic resistance and should be enhanced by retrofitting as soon as possible. （3） The percentage of buildings in extensive damage or collapsed were very high, resulting in extremely high economy, environment, and resource costs, hence it is of great importance to improve the seismic resilience of cities. The outcomes of this work could provide a useful method and application case for future works on urban seismic damage prediction of buildings.