一种基于灵敏度矩阵进行桥梁损伤识别的方法

A Method for Bridge Damage Identification Based on Sensitivity Matrix

重点研究了一种基于灵敏度矩阵对桥梁进行损伤识别的方法。基于振动分析的矩阵摄动理论,首先讨论了求取模态参数对结构物理参数灵敏度矩阵的方法,形成灵敏度矩阵的过程中避免了偏微分计算;基于灵敏度矩阵,建立了桥梁的损伤识别模型,并给出了此模型具体的求解方法;然后利用Guyan缩减的方法来缩减结构的模态自由度,保证了在进行损伤识别的过程中利用较少的模态参数,进而提高了方法的实用性;最后把所述方法应用于三跨预应力混凝土连续箱梁桥的实际损伤诊断工程。结果表明,利用所述方法进行预应力混凝土连续梁桥的损伤识别是有效的。

A method for bridge damage identification based on the sensitivity matrix theory was mainly studied. Firstly, sensitivity matrix of modal parameters with respect to structural physical parameters was obtained based on matrix perturbation theory, and partial derivatives calculation was avoided in the process of formulating the sensitivity matrix of structures.The damage identification model of bridge was established based on sensitivity matrix, and its specific solving method was presented. Then Guyan reduction method was adopted to reduce the modal freedom degree of structures to guarantee that less mode parameters are needed during formulating structural sensitivity and to improve the practicability of this method. Finally this method was applied on an actual demage identification project of a 3-span prestressed concrete continuous box-girder bridge. The results Show that this method is effective for damage identification of prestressed concrete continuous beam bridge.