高桩码头桩基动力损伤识别方法

Identification method for pile foundation' s dynamic damage of piled wharf

结构的损伤对其动力特性会产生一定的影响,利用结构损伤前后的模态参数的变化来进行结构的损伤识别是行之有效的方法。然而结构在完整状态下的模态参数很难得到,损伤程度更是难以确定。针对上述问题,提出一种基于损伤状态下的拟合曲率模态的损伤识别方法:首先通过损伤后的位移模态拟合出无损伤位移模态,然后根据拟合出的位移模态得到拟合曲率模态,基于损伤后的真实曲率模态相对于拟合曲率模态的突变来判别损伤位置;引入曲率相对改变量、损伤位置参数和模态阶数作为损伤样本的特征向量,通过支持向量机判断结构损伤程度。实例分析表明该方法能够对高桩码头排架结构的损伤进行识别。

The structural damage has a certain effect on structural dynamic characteristics, and it is an effective method to use the change between the modal parameters of damaged structure and undamaged structure. However, it is difficult to obtain the modal parameters of structures which in intact state, and the damage degree is more difficult to determine. To counter the above problem, we putting forward a damage identification method based on the fitting curvature of damaged state, I. e. fitting displacement modal of intact state from displacement modal of damaged state firstly, then getting curvature modal from the fitting displacement modal, judging the damage location based on mutations of real modal curvature relative to the fitting curvature modal; introducing relative change of curvature, the damage location parameters and modal order as the feature vector of structure damage damage degree through the support vector machine. The instance analysis shows that sample, determining the proposed method can detect the damage of pile foundation of the piled wharf.