基于泰勒展开的混凝土超声测试温度效应研究

Study on temperature effect of concrete ultrasonic testing based on Taylor expansion

为研究环境温度对混凝土超声尾波信号的影响,在室内自然环境条件下,采集环境温度变化下的混凝土工字梁超声尾波信号。利用泰勒展开,分温度区段进行分析处理超声尾波信号,逐步提取信号中各阶温度效应成分并逐一去除,建立各阶信号投影系数与温度效应的拟合关系。结果表明:一阶信号投影系数与温度效应拟合直线的拟合优度高于0.98;去除前二阶温度效应成分后,平均去相关系数可降低97%以上。

To study the effect of environmental temperature on the ultrasonic coda signal of concrete,the ultrasonic coda signal of concrete I-beams was collected under indoor natural environmental conditions under changes in environmental temperature.Using Taylor expansion,analyze and process the ultrasonic wake signal in different temperature ranges,gradually extract the temperature effect components of each order in the signal and remove them one by one,and establish a fitting relationship between the amplitude projection coefficients of each order and the temperature effect.The results show that the goodness of fit between the first-order amplitude projection coefficient and the temperature effect fitting line is higher than 0.98;After removing the first and second order temperature effect components,the average decorrelation coefficient can be reduced by more than 97%.