梁结构损伤诊断直接指标法应用

The Application of Direct Index Method of Beam Damage Location Detection

结构损伤识别主要是对各种工程结构进行检测并对检测结果做适当的分析,从而确定结构的健康状况。有研究表明应变模态比固有频率和振型对局部损伤更敏感,可以很好地进行结构损伤识别。结合有限元方法和直接指标法ISMSD(Strain Mode Shape Difference),无需原始模态数据,只根据损伤后的经三次样条插值的光滑应变模态差分曲线即可进行相关计算。文章应用该方法对假定损伤简支梁在多种不同损伤程度情况进行数值仿真计算,并给出损伤位置直接指标曲线。结果表明,该指标法能正确地判定损伤位置,尤其是损伤量较小时。

Structural damage identification mainly determines the structure health status and analyzes the test results. Certain research results show that strain mode can be more sensitive and effective to local damage. The direct index method of damage location detection ISMSD is based on difference theory, without the modal parameter of the original structure. FEM numerical simulation to partial crack with different degree is also done. The criteria of damage location detection are obtained by strain mode difference curve through three times spline interpolation. The direct index method can accurately detect damage location, especially lower damage.