基于嵌入压电技术的钢管核心混凝土缺陷检测

钢管混凝土构件核心混凝土缺陷影响到其延性和承载力。利用自制的嵌入式压电功能元,该文提出了基于压电陶瓷应力波测量与分析的核心混凝土缺陷监测方法。通过对比不同状态简谐激励下测量信号幅值和扫频激励下小波包能量的差异,定义了基于测量信号幅值和小波包能量的损伤指标。结果表明,利用所提出的嵌入式压电技术和所定义的损伤指标,有效地识别了钢管混凝土构件的核心混凝土损伤,损伤指标对损伤程度敏感。

Experimental Study on Defect Detection of Concrete Core of Concrete Filled Steel Tubular with Embedded PZT

Defect in the concrete core of concrete filled steel tubular (CFST) would lead to the reduction of its load carrying capability and the ductility. A concrete core defect detection approach for CFST specimens based on the measurement and analysis on the stress wave propagating was proposed with the assistance of embedded PZT based function elements which acted as both actuators and sensors. Based on the comparison on the amplitudes and the corresponding wavelet packet energy values of the measurement when sinusoidal and sweep signals were used respectively, two evaluation indices were defined. Test results showed that the proposed method was effectively to identify the defects of the concrete core and the defined indices were sensitive to the extent of concrete core defects.