基础隔震结构基于实时监测数据的多级预警及其在南京博物院老大殿中的应用  

Multi-level early-warning system for base-isolated structures based on real-time monitoring data and its application on the Old Hall of Nanjing Museum

作　　者：石晟 杜东升[1] 徐敬海 王曙光[1] SHI Sheng;DU Dongsheng;XU Jinghai;WANG Shuguang(College of Civil Engineering,Nanjing Tech University,Nanjing 211816,China;College of Geometrics and Technology,Nanjing Tech University,Nanjing 211816,China)

机构地区：[1]南京工业大学土木工程学院,江苏南京211816 [2]南京工业大学测绘科学与技术学院,江苏南京211816

出　　处：《建筑结构学报》2022年第4期47-57,共11页Journal of Building Structures

基　　金：国家自然科学基金项目(51678301,51678302)。

摘　　要：南京博物院老大殿是经过抬升3 m后又进行隔震加固的历史文物建筑,对其进行结构安全性监测并建立预警系统具有重大的工程意义。因此,提出了一种三级预警阈值体系,并以南京博物院老大殿安全性监测系统的实测数据为依据,验证了该阈值系统的有效性和合理性。首先,基于非线性自回归神经网络模型提出一种动态预警阈值设计方法,用于确定第一级预警阈值;然后,选取20条符合当地规范反应谱的地震波,将第二级预警阈值设为非线性动力时程分析得到的支座位移均值;第三级预警阈值设为规范规定的隔震支座在罕遇地震下水平最大允许变形值;最后,提出一种综合预警的实施框架,根据三个级别预警阈值在短期内的超越情况,实现红、黄、蓝三级报警级别的综合评定,作为选择应急预案的基础。通过南京博物院老大殿的OpenSEES模型进行数值模拟,并结合实测数据验证。结果表明,该方法可以有效识别出由支座刚度变化引起的异常位移值。The Old Hall of Nanjing Museum is a historical building,which has been uplifted by 3 m and then retrofitted by seismic isolation.Therefore,it is of great engineering significance to monitor the structural safety and establish an early-warning system.A three-level early-warning system was proposed in this paper,and the monitoring data obtained from the Old Hall of Nanjing Museum was taken as research basis to verify the proposed method.Firstly,a dynamic warning threshold design method based on the nonlinear auto-regressive neural network was proposed,which was used to determine the first level threshold.Twenty spectrum-compatible ground motions were selected from the PEER ground motion database,and the second level threshold was taken as the mean displacement of isolation bearings obtained by nonlinear dynamic time history analysis.The third level threshold was set as the specified maximum allowable deformation of isolation bearings under rare earthquakes.Based on the threshold exceeding during a certain period of time,an integrated warning technology was proposed to determine the alarm levels of blue,yellow and red,which served as the basis for the selection of emergency response plan.From the simulation results and monitoring data of the Old Hall of Nanjing Museum,the presented method is proved to be effective in detecting anomalies caused by sudden change of stiffness of isolation bearings.

关 键 词：文物建筑 基础隔震 结构健康监测 实时预警 非线性自回归模型 神经网络 

分 类 号：TU352.12[建筑科学—结构工程]