运营环境下混凝土简支梁桥裂缝的非线性损伤识别  

Nonlinear damage identification of cracks of the concrete simply-supported bridge under operational environment

作　　者：蒋燕芳 蒋伟 刘纲[1,2] 张衡[1] JIANG Yanfang;JIANG Wei;LIU Gang;ZHANG Heng(School of Civil Engineering;Key Laboratory of New Technology for Construction of Citiesin Mountain Area,Ministry of Educations,Chongqing University,Chongqing 400045,P.R.China)

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]重庆大学山地城镇建设与新技术教育部重点实验室,重庆400045

出　　处：《重庆大学学报（自然科学版）》2020年第5期59-66,共8页Journal of Chongqing University

基　　金：国家自然科学基金(面上)项目(51578095)。

摘　　要：针对混凝土简支梁桥常见的开裂病害,基于改进的Hilbert-Huang变换(HHT)提出裂缝的非线性损伤识别方法。选取曲率曲线型呼吸裂缝模型并将其融入车桥耦合共振系统,以更真实地模拟运营环境下裂缝的非线性开闭现象。引入镜像延拓法和集合经验模态分解法分别改进传统HHT算法的端点发散和模态混叠问题,提取桥梁加速度响应的能量时程曲线,将能量时程曲线尖峰出现时刻和相对幅值比分别作为损伤定位和定量的特征指标,从而建立简支梁裂缝的非线性损伤识别方法。数值算例表明,采用单一传感器便可通过文中方法识别简支梁开裂的部位和程度,为混凝土简支梁的损伤识别提供技术支撑。A non-linear damage detection method for cracks of the concrete simply-supported bridge based on the improved Hilbert-Huang transfer(HHT) is proposed in this work. The curvilinear breathing crack model controlled by curvature is employed to consider the breathing phenomenon of cracks, and the model is integrated into vehicle-bridge interaction system to simulate operational environment. The mirror extension and ensemble empirical mode decomposition algorithm are introduced to eliminate the end effect and mode mixing problems respectively. The energy time history from the acceleration response of the bridge under operational condition is acquired using the improved HHT algorithm, and then the appearance time and relative amplitude ratio from the peak of the energy time history are extracted as features to localize and quantify damage respectively. Numerical results show that the location and severity of the cracking damage can be successfully identified using only one sensor deployed on the bridge, which provides technical support to damage detection of cracks on the concrete simply-supported bridge.

关 键 词：非线性损伤识别 呼吸裂缝 HHT变换 车桥耦合 能量时程曲线 

分 类 号：TH212[机械工程—机械制造及自动化] TH213.3