为了实现对在役结构桩基小损伤高精度识别,根据桩基损伤后的振动特征微分方程,建立由模态损伤灵敏度因子、单元损伤因子、单元模态应变能组成的结构损伤识别方程.在应用模态损伤灵敏度因子选择高效损伤识别模态的基础上,应用损伤前后应变能的变化和小波分析技术对桩基的小损伤进行精确损伤定位识别.在损伤定位识别的基础上,应用损伤识别方程对桩基的小损伤进行损伤程度诊断.应用本文所提出的方法对SF-1灯塔桩基进行损伤数值模拟识别,识别误差小于5%,验证了该损伤识别方法具有较高识别精度.最后应用该方法对在役BHX-12平台的桩基损伤进行识别,识别结果和实际损伤比较吻合.
In order to identify the small damage of serving structural pile in high prelision, according to the structural vibration equation of damaged pile, a structural damage identification equation was established which contained modal damage sensitivity factor, the element damage factor and element modal strain energy. Efficient damage identification modals were selected by applying modal damage sensitivity factor. Accurate damage location identification method was established for pile small damage by using efficient damage identification modals and wavelet analysis techniques. On the basis of the damage location identification, the injury severity could be identified by using structural damage identification equation. Numerical simulation of the SF-1 lighthouse pile foundation damage identification was done by applying the proposed method, the result of errors of identification were less than 5% which verified that the proposed method had higher recognition accuracy. The pile foundation damage in the BHX-12 platform was detected by applying the proposed method, the consistent of identification result and actual result proved the practicality of the method.