考虑实测信息的既有规则建筑状态识别与抗震性能快速评估

State identification and seismic performance rapid assessment of existing regular building structures by considering field measured information

城市既有建筑(群)的地震安全性评价面临高效分析、快速评估、定量判定的多重技术发展需求。考虑长期服役过程中的结构性能演化现象,既有建筑安全性评价需要结构本身和当地地震动等一系列实测数据与信息,以标定结构真实服役状态,保证结构抗震性能评估结果的准确性,并兼顾结构抗震性能分析的时效性。本文基于等效非线性单自由度模型,结合作者近年来在数据驱动型状态评估指标方面的研究成果,提出了以既有建筑实测模态频率和阻尼比映射结构宏观服役状态,结合当地实测地震动数据集,快速评估该目标建筑抗震安全性的方法。阐述了基于动力测试和HAZUS技术手册的既有结构等效非线性单自由度模型的建立过程,提出了两类结构状态评价指标,结合多元工程性能参数,建立了等效模型变形状态与不同抗震性能水准之间的直接联系。以四川省珙县当地一栋高层规则框架结构和2019至2022年间10次实测地震动为例,对该建筑在当地近期实际地震动作用下的抗震安全性进行评估。

The seismic safety evaluation of existing urban buildings(groups) is faced with multiple technical development of efficient analysis,rapid evaluation and quantitative determination.Considering the evolution of structural performance during the longterm service life,the safety evaluation of in-service buildings requires design and measurement information on the structures as well as regional ground motions to calibrate the real conditions of the structures,which can ensure the accuracy of the performance evaluation results within an acceptable timeliness.Based on the equivalent nonlinear single-degree-of-freedom model and the authors' recent research on data-driven performance assessment index,this study proposes a method to map the global conditions of the structure with the measurement modal information and assess the seismic safety of the target building using the regional dataset of measured ground motion further.Based on the field testing and the HAZUS technical manual,the procedure of establishing the equivalent nonlinear single-degree-of-freedom representing the existing building is described.Two structural condition evaluation indicators are proposed,combined with multivariate engineering performance parameters,and the relationship between the deformation of an equivalent model and different seismic performance levels is further established.A high-rise regular RC frame structure located in Gongxian,Sichuan Province is considered as an example,the seismic safety of this building subjected to 10 local earthquakes measured from 2019 to 2022 is evaluated.