基于非线性声学的混凝土损伤无损检测技术研究

 王枝枝,廖艳鹤,王留洋

(长安大学 公路学院,陕西 西安 710064

  要:利用透射式扫描方法对四组含有裂缝的混凝土试件进行检测,测量透射超声波基波、二次谐波和三次谐波的幅值;对时域信号进行频谱分析,计算谐波含有率、非线性参数。结果显示:谐波含有率、非线性参数都随水灰比的增大而增大;三次谐波含有率比二次谐波含有率高,因此三次谐波在检测混凝土中的损伤时有更高的灵敏度;用窄带超声换能器发射超声波得到的透射波中基波衰减幅度更大,测量灵敏度更高。

关键词:非线性超声检测谐波含有率非线性参数水灰比

中图分类号U446                   文献标识码A

Using Nonlinear Ultrasonic Techniques

in Non-destructive Testing of Concrete

WANG Zhi-zhiLIAO Yan-heWANG Liu-yang

The highway college of chang'an universityXi‘an 710064China

AbstractThe concrete specimens were detected with transmission scanning method. Amplitudes of fundamental wavessecond and third harmonic waves were measured through processing the obtained RF signal, harmonic ratio and nonlinear parameters were calculated by the analysis of time domain signal. The results showed that both the harmonic ratios and nonlinear parameters were found to increase as the water cerement ratio increased. Because of the increases of third harmonic ratio were higher than the second harmonic ratio, the third harmonic ratio had a higher sensitivity. The attenuation of fundamental waves got by narrowband transmitting ultrasonic transducer as relatively largeindicating a higher sensitivity.

Key words: nonlinear ultrasonic testingharmonic rationonlinear parameterswater cement ratio