井架结构损伤的动力学识别

Dynamic detection of derrick damage structures

针对JJ160/41-K型井架结构的损伤情况,研究了结构损伤动力学检测方法,包括柔度矩阵差值法、曲率模态法和柔度曲率法,分析了柔度矩阵差值法和曲率模态法应用于损伤检测的局限性,以及柔度曲率法的优点.井架应用结果表明:柔度差值法在损伤位置间距较近或各位置损伤程度较小的情况下识别精度较差;各处损伤部位间的相互影响以及损伤部位对未损伤部位的影响,会使曲率模态法对结构损伤识别的敏感度下降;柔度曲率法能够反映损伤存在、位置及程度,且各损伤部位之间不存在相互影响,识别精度高,适合在井架结构损伤的在线检测中推广应用.

In this paper,structure kinetic detection methods for damaged structures were investigated to monitor damage instance of JJ160/41-K oil derrick.The flexibility difference method,the curvature mode method and the flexibility curvature method were used in the structure kinetic detection methods.The limitation of the flexibility difference method and the curvature mode law were analyzed,and the advantage of flexibility curvature method was also analyzed.The application of derrick showed that the detection precision of the flexibility difference method was low when the space of the damage points was near and the damage degree was slight.The interaction of damage points and the influence of the damage points to the undamaged points would make the precision of curvature mode method lower.The flexibility curvature could reflect damage existence,size,location,and damage points were not interactional,the detection precision was high.It was suited to use and generalized in on-line test of derrick structure damage.