【摘要】 结构损伤识别是混凝土结构健康监测的核心技术之一,其结构损伤识别特征参数的选取非常重要。文中以代表性较强的压电陶瓷材料(锆钛酸铅即PZT)为例,分5组工况,即1组健康工况,4组损伤工况对混凝土梁进行了裂缝损伤识别试验,并分析了各损伤工况下信号参数随损伤程度的变化情况。提取到信号的幅值、主频以及相位3个参数可作为判定结构损伤的情况,其中信号的幅值对混凝土结构裂缝损伤较为敏感且能预测损伤的发展趋势。结果表明,监测信号的幅值,可作为判断结构健康状态及损伤程度的敏感因子,结构损伤愈大,信号的衰减程度愈大。更多还原

【Abstract】 The structural damage detection is one of the main techniques in concrete inspection,and the selection for characteristic parameters is very important in the detection.An experimental method of crack detection for concrete structures embedded with PZT sensors is presented here.The detecting signals are respectively analyzed in the time and frequency domain,and the parameters such as the amplitude,frequency and phase of the signals are extracted as factors to evaluate the structural damage.The damage-sensitive factors for the concrete structure are found out and used to predict the trend of the crack development by analysis of the change of the signal parameters in various damage cases with the damage levels.The experimental results show that the signal amplitude is the most sensitive in all parameters to the crack damage,and the greater the damage level,the greater the attenuation degree.更多还原