采用复连续小波变换的桩基损伤位置识别方法

提出基于复连续小波变换(CCWT)的桩基损伤位置识别方法.首先,对响应信号进行复连续小波变换,得到小波系数矩阵;然后,分析不同频段的相位角,确定桩身损伤位置;最后,通过桩基三维有限元模型数值算例和桥梁桩基实例,对基于复连续小波变换的桩基损伤位置识别方法进行验证.结果表明:复连续小波变换不但能够准确估计桩长,而且能够捕捉相位图上的交叉点,实现桩身损伤位置识别;与传统损伤检测方法相比,复连续小波变换可凸显响应信号的相位信息,成功识别桩身微小损伤的位置;但该方法在识别过程中出现较多的干扰点,需要借助其他桩身损伤检测方法进行判定和排除.

Damage Localization Method of Piles Using Complex Continuous Wavelet Transform

The complex continuous wavelet transform(CCWT)was introduced to localize pile damage. CCWT was performed on the response signal to obtain wavelet coefficient matrix. The resultant coefficients were adopted to construct phase angles at different frequency bands, and to locate the pile damage. 3D finite element model of a pile and an example of a real bridge pile were used to investigate the CCWT based on damage localization method. The results show that CCWT is capable of estimating pile length accurately and localizing pile damage by capturing the crossing points in the phase diagram. Compared with the traditional damage detection method, the complex continuous wavelet transform highlights the phase information of the response signal and successfully identifies the location of the tiny damage of the pile body; however, this method also has a few interference points in the identification process, which needs to be judged and excluded by other pile damage detection methods.