基于导波的钢板-混凝土界面黏结性能评价研究

Bond behavior evaluation of steel plate-concrete interface based on guided wave

通过基于导波的宽带激励信号对不同脱粘情况下的黏钢加固混凝土二维有限元模型的界面脱粘缺陷进行检测,在此基础上对带有不同脱粘缺陷的黏钢加固混凝土试件进行试验探究,通过模态分析法和小波包能量谱法对接收信号进行信号处理,发现通过未知构件与完全黏结试件之间的归一化互相关系数可判断钢板-混凝土界面是否脱粘;通过模态分析法,根据一次反射模态导波A_(0)/A_(0)的到达时间和脱粘指标可定量判断脱粘的位置;通过小波包能量谱分析方法可判定脱粘的程度。该方法为实际工程中的钢板-混凝土界面脱粘检测提供理论与技术支撑。

By using 2D finite element modeling(FEM)method,the interface debonding defects of bonded steel-reinforced concrete under different debonding conditions were detected by broadband excitation signals based on guided wave.Based on the FEM results,experimental investigation was carried out on the bonded steel-reinforced concrete specimens with different debonding defects.The received signals were processed by modal analysis method and wavelet packet energy spectrum method.The results show that whether the steel plate concrete interface is debonded or not can be verified by the normalized cross-correlation coefficient between the unknown component and the fully bonded specimen.The location of interface debonding can be quantitatively judged by the arrival time of the first reflection mode guided wave A_(0)/A_(0) and debonding index based on model analysis method.The extent of interface debonding can be determined by wavelet packet energy spectrum analysis.This method provides theoretical and technical support for the debonding detection of steel plate-concrete interface in engineering.