钢管混凝土拱桥健康监测传感器优化布置方法

Optimal placement of sensors for health monitoring of concrete filled steel tube arch bridge

提出一种针对超大跨钢管混凝土拱桥健康监测传感器的多重优化布置方法以保证桥梁在建设与营运阶段的安全性。首先以Fisher信息矩阵2-范数的变化率来优化目标模态数量,再综合考虑模态置信度矩阵非对角元的最大值及均值来优化传感器数量,最后基于有效独立法优化传感器的布置位置。以某主跨575 m的中承式钢管混凝土拱桥为例,通过有限元软件提取了结构的模态数据,根据多重优化布置方法对传感器的数量及位置进行了优化分析,结果表明:对于超大跨钢管混凝土拱桥,曲率模态是拱肋损伤识别的有效方法,确定传感器数量时要综合考虑模态置信度矩阵非对角元的最大值及均值。

Bridge health monitoring is important for the safety of bridges during construction and operation.Optimization of the quantity and location of sensors under the test requirement is the key point for bridge health monitoring.A multi-optimal placement method of sensors for health monitoring of long-span concrete-filled steel tube(CFST)arch bridge was proposed.The change rate of 2-norm of Fisher information matrix was firstly used to determine the numbers of target mode.Then the quantity of sensors was determined by comprehensively consideration of the maximum and the average value of the off-diagonal elements of the modal assurance criterion matrix.Finally,the sensors location was determined by effective independence method.The multi-optimal placement of sensors of a half-through CFST arch bridge with a main span of 575 m was taken as an example according to the modal data extracted by the finite element software.The results show that the curvature mode was an effective damage detection method for long-span CFST arch bridge.The maximum off-diagonal element and the average value of the off-diagonal elements of the modal assurance criterion matrix should be considered when the number of sensors was determined.