古建筑木结构地震损伤分析及抗侧刚度识别
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摘要
为研究地震作用下古建筑木结构层间抗侧能力损伤和识别,根据缩尺比为1∶3.52殿堂式古建筑木结构振动台试验,分析不同地震损伤下模型层间等效抗侧刚度、侧移响应及侧移对刚度损伤的敏感性.在考虑柱脚滑移的结构简化力学模型基础上,推导模型的状态方程和观测方程.考虑试验环境噪声干扰,利用奇异值分解偏最小二乘(PLS-SVD)和扩展卡尔曼滤波(EKF)方法定量识别模型等效抗侧刚度.结果表明,随着地震损伤增加,结构层间等效抗侧刚度比减小、侧移峰值对柱架层结构损伤较乳层敏感.无损工况下结构等效抗侧刚度识别误差在10%左右;损伤工况下结构等效抗侧刚度识别误差为15%～20%.通过明代古建筑木结构西安钟楼等效抗侧刚度在线识别,验证了PLS-SVD和EKF方法可为古建筑木结构等效抗侧能力监测和震前抗倒塌预警提供理论依据.
In order to study the inter-story lateral stiffness damage and identification of ancient wooden struc-tures under strong earthquakes, the inter-story lateral stiffness, lateral displacement response and the sensitivity of displacement to stiffness were analyzed by the shaking table test of an ancient timber frame with a scale ratio 1:3.52.Based on the simplified mechanics model considering the column sliding, the structural state equation and observa-tion equation were deduced. Considering the influence of noise, the lateral stiffness was identified by means of Par-tial Least Squares-Singular Value Decomposition(PLS-SVD)and Extended Kalman Filter(EKF). The analysis results show that the ratio of inter-story lateral stiffness gradually decreases with the increase of seismic damage. The damage of column layer is especially sensitive to the increase of lateral displacement. The identified error of the lat-eral stiffness is about 10% without damage. Under the damage condition, the identified error of the lateral stiffness is about 15%～20%. Through the lateral stiffness identification of Bell Tower of Xi'an, it indicates that the method of PLS-SVD and EKF has high accuracy and good applicability, and can provide a theoretical basis for monitoring the change of lateral stiffness and offering warning before structural collapse.
In order to study the inter-story lateral stiffness damage and identification of ancient wooden struc-tures under strong earthquakes, the inter-story lateral stiffness, lateral displacement response and the sensitivity of displacement to stiffness were analyzed by the shaking table test of an ancient timber frame with a scale ratio 1:3.52.Based on the simplified mechanics model considering the column sliding, the structural state equation and observa-tion equation were deduced. Considering the influence of noise, the lateral stiffness was identified by means of Par-tial Least Squares-Singular Value Decomposition(PLS-SVD)and Extended Kalman Filter(EKF). The analysis results show that the ratio of inter-story lateral stiffness gradually decreases with the increase of seismic damage. The damage of column layer is especially sensitive to the increase of lateral displacement. The identified error of the lat-eral stiffness is about 10% without damage. Under the damage condition, the identified error of the lateral stiffness is about 15%～20%. Through the lateral stiffness identification of Bell Tower of Xi'an, it indicates that the method of PLS-SVD and EKF has high accuracy and good applicability, and can provide a theoretical basis for monitoring the change of lateral stiffness and offering warning before structural collapse.
引文
[1] ZHANG X C,XUE J Y,ZHAO H T,et al. Experimental study on Chinese ancient timber-frame building by shaking table test[J].Structural Engineering and Mechanics,2011,40(4):453—457.
[2]谢启芳,薛建阳,赵鸿铁.汶川地震中古建筑的震害调查与启示[J].建筑结构学报,2010,31(增刊2):18—23.XIE Q F,XUE J Y,ZHAO H T. Seismic damage investigation and analysis of ancient buildings in Wenchuan earthquake[J]. Journal of Building Structures,2010,31(Suppl2):18—23.(In Chinese)
[3]程亮,王焕定.等效剪切刚度的框架结构损伤识别方法[J].哈尔滨工业大学学报,2009,41(10):36—40.CHENG L,WANG H D. Damage identification approach of frame structure based on equivalent shear stiffness[J]. Journal of Harbin Institute of Technology,2009,41(10):36—40.(In Chinese)
[4]王娟,杨庆山.藏式古建筑木结构损伤识别的数值模拟[J].振动、测试与诊断,2014,34(1):160—167.WANG J,YANG Q S. Numerical simulation of damage identification for Tibetan ancient timber structure[J]. Journal of Vibration,Measurement&Diagnosis,2014,34(1):160—167.(In Chinese)
[5]王鑫,胡卫兵,孟昭博.基于小波包能量曲率差的古木结构损伤识别[J].振动与冲击,2014,33(7):153—159.WANG X,HU W B,MENG Z B. Damage detection of an ancient wood structure based on wavelet packet energy curvature difference[J]. Journal of Vibration and Shock,2014,33(7):153—159.(In Chinese)
[6]陈清军,周成杰,杨永胜.基于环境振动信号的框架结构震后损伤识别[J].湖南大学学报(自然科学版),2014,41(9):20—26.CHEN Q J,ZHOU C J,YANG Y S. Damage identification of frame structure after earthquakes based on environmental vibration records[J]. Journal of Hunan University(Natural Sciences),2014,41(9):20—26.(In Chinese)
[7]杨斌,程军圣.基于WPD-LMD和排列熵的结构损伤识别方法[J].湖南大学学报(自然科学版),2014,41(8):41—46.YANG B,CHENG J S. Damage identification based on wavelet packet decomposition-local mean decomposition and permutation entropy[J]. Journal of Hunan University(Natural Sciences),2014,41(8):41—46.(In Chinese)
[8]周云,蒋运忠,易伟健,等.基于模态柔度理论的结构损伤诊断试验研究[J].湖南大学学报(自然科学版),2015,42(5):36—45.ZHOU Y,JIANG Y Z,YI W J,et al. Experimental research on structural damage detection based on modal flexibility theory[J].Journal of Hunan University(Natural Sciences),2015,42(5):36—45.(In Chinese)
[9]罗钧,刘纲,黄宗明.基于约束最小二乘法的剪切型框架结构损伤识别新方法[J].振动与冲击,2016,35(20):119—124.LUO J,LIU G,HUANG Z M. Damage detection for a shear frame structure based on the constrained least squares method[J]. Journal of Vibration and Shock,2016,35(20):119—124.(In Chinese)
[10]赵博宇,丁勇,吴斌.基于扩展卡尔曼估计算法的地震模拟振动台模型识别[J].振动与冲击,2014,33(12):145—150.ZHAO B Y,DING Y,WU B. Identification of shaking table model for seismic simulation based on an extended Kalman estimator[J].Journal of Vibration and Shock,2014,33(12):145—150.(In Chinese)
[11]姚侃,赵鸿铁.木构古建筑柱与柱础的摩擦滑移隔震机理研究[J].工程力学,2006,23(8):127—131.YAO K,ZHAO H T. Study on the mechanism of sliding friction shock isolation between timber column and plinth in historical buildings[J]. Engineering Mchanics,2006,23(8):127—131.(In Chinese)
[12]李国强,李杰.工程结构动力检测理论与应用[M].北京:科学出版社,2002:173—194.LI G Q,LI J. Theory and application of dynamic detection for engineering structures[M]. Beijing:Science Press,2002:173—194.(In Chinese)
[13]孟昭博.西安钟楼的交通振动响应分析与评估[D].西安.西安建筑科技大学土木工程学院,2009:37—44.MENG Z B. Analysis and assessment of the vibration response traffic-induced of Xi′an Bell Tower[D]. Xi′an:School of Civil Engineering,Xi′an University of Architecture and Technology,2009:37—44.(In Chinese)
[14]曾建.交通激励作用下西安钟楼动力特性分析[D].西安.西安建筑科技大学土木工程学院,2013:38—43.ZENG J. The dynamic characteristics analysis of Xi′an Bell Tower under traffic incentives[D]. Xi′an:School of Civil Engineering,Xi′an University of Architecture and Technology,2013:38—43.(In Chinese)
[2]谢启芳,薛建阳,赵鸿铁.汶川地震中古建筑的震害调查与启示[J].建筑结构学报,2010,31(增刊2):18—23.XIE Q F,XUE J Y,ZHAO H T. Seismic damage investigation and analysis of ancient buildings in Wenchuan earthquake[J]. Journal of Building Structures,2010,31(Suppl2):18—23.(In Chinese)
[3]程亮,王焕定.等效剪切刚度的框架结构损伤识别方法[J].哈尔滨工业大学学报,2009,41(10):36—40.CHENG L,WANG H D. Damage identification approach of frame structure based on equivalent shear stiffness[J]. Journal of Harbin Institute of Technology,2009,41(10):36—40.(In Chinese)
[4]王娟,杨庆山.藏式古建筑木结构损伤识别的数值模拟[J].振动、测试与诊断,2014,34(1):160—167.WANG J,YANG Q S. Numerical simulation of damage identification for Tibetan ancient timber structure[J]. Journal of Vibration,Measurement&Diagnosis,2014,34(1):160—167.(In Chinese)
[5]王鑫,胡卫兵,孟昭博.基于小波包能量曲率差的古木结构损伤识别[J].振动与冲击,2014,33(7):153—159.WANG X,HU W B,MENG Z B. Damage detection of an ancient wood structure based on wavelet packet energy curvature difference[J]. Journal of Vibration and Shock,2014,33(7):153—159.(In Chinese)
[6]陈清军,周成杰,杨永胜.基于环境振动信号的框架结构震后损伤识别[J].湖南大学学报(自然科学版),2014,41(9):20—26.CHEN Q J,ZHOU C J,YANG Y S. Damage identification of frame structure after earthquakes based on environmental vibration records[J]. Journal of Hunan University(Natural Sciences),2014,41(9):20—26.(In Chinese)
[7]杨斌,程军圣.基于WPD-LMD和排列熵的结构损伤识别方法[J].湖南大学学报(自然科学版),2014,41(8):41—46.YANG B,CHENG J S. Damage identification based on wavelet packet decomposition-local mean decomposition and permutation entropy[J]. Journal of Hunan University(Natural Sciences),2014,41(8):41—46.(In Chinese)
[8]周云,蒋运忠,易伟健,等.基于模态柔度理论的结构损伤诊断试验研究[J].湖南大学学报(自然科学版),2015,42(5):36—45.ZHOU Y,JIANG Y Z,YI W J,et al. Experimental research on structural damage detection based on modal flexibility theory[J].Journal of Hunan University(Natural Sciences),2015,42(5):36—45.(In Chinese)
[9]罗钧,刘纲,黄宗明.基于约束最小二乘法的剪切型框架结构损伤识别新方法[J].振动与冲击,2016,35(20):119—124.LUO J,LIU G,HUANG Z M. Damage detection for a shear frame structure based on the constrained least squares method[J]. Journal of Vibration and Shock,2016,35(20):119—124.(In Chinese)
[10]赵博宇,丁勇,吴斌.基于扩展卡尔曼估计算法的地震模拟振动台模型识别[J].振动与冲击,2014,33(12):145—150.ZHAO B Y,DING Y,WU B. Identification of shaking table model for seismic simulation based on an extended Kalman estimator[J].Journal of Vibration and Shock,2014,33(12):145—150.(In Chinese)
[11]姚侃,赵鸿铁.木构古建筑柱与柱础的摩擦滑移隔震机理研究[J].工程力学,2006,23(8):127—131.YAO K,ZHAO H T. Study on the mechanism of sliding friction shock isolation between timber column and plinth in historical buildings[J]. Engineering Mchanics,2006,23(8):127—131.(In Chinese)
[12]李国强,李杰.工程结构动力检测理论与应用[M].北京:科学出版社,2002:173—194.LI G Q,LI J. Theory and application of dynamic detection for engineering structures[M]. Beijing:Science Press,2002:173—194.(In Chinese)
[13]孟昭博.西安钟楼的交通振动响应分析与评估[D].西安.西安建筑科技大学土木工程学院,2009:37—44.MENG Z B. Analysis and assessment of the vibration response traffic-induced of Xi′an Bell Tower[D]. Xi′an:School of Civil Engineering,Xi′an University of Architecture and Technology,2009:37—44.(In Chinese)
[14]曾建.交通激励作用下西安钟楼动力特性分析[D].西安.西安建筑科技大学土木工程学院,2013:38—43.ZENG J. The dynamic characteristics analysis of Xi′an Bell Tower under traffic incentives[D]. Xi′an:School of Civil Engineering,Xi′an University of Architecture and Technology,2013:38—43.(In Chinese)