基于单元模态应变能和剩余模态力的结构损伤识别方法在某塔式桁架中的应用

Application of structural damage identification method based on element modal strain energy and residual modal force in tower truss

为快速、准确定位工程结构损伤位置,有效提高工程结构安全性能和使用寿命,以某塔式桁架结构为研究对象,运用单元模态应变能法和剩余模态力法对其进行损伤识别.利用MSC Marc对该桁架完整结构和几种不同损伤程度下的损伤结构进行模态分析,通过MATLAB编程从模态分析结果中提取这些结构的模态参数,计算损伤结构单元模态应变能的变化率和损伤结构各节点自由度对应的剩余模态力,并进行结构损伤识别.结果表明单元模态应变能变化率和剩余模态力是有效和准确的结构损伤标志量.

To identify damage location of engineering structures rapidly and accurately and improve the safety performance and service life effectively,the damage identification of a tower truss is performed by element modal strain energy method and residual modal force method.The truss mode is analyzed for a healthy structure and several kinds of structures with different damage degree by MSC Marc;the modal parameters of the structures are extracted from the modal analysis results by MATLAB programming;the change rate of element modal strain energy and residual modal force corresponding to degree of freedom of each structural node are calculated and the structure damage is identified.The results indicate that the change rate of element modal strain energy and residual modal force are effective and accurate identifiers for structural damage identification.