地质雷达在岩溶陷落柱探测中的应用研究

Study on Application of Ground Penetrating Radar in Karst Collapse Column Detection

以某隧道洞底陷落柱为例,通过地质雷达对目标体的探测,分析岩溶陷落柱的雷达波组异常特征,准确地探测出陷落柱的位置、规模和埋深;同时,选取典型的雷达波进行频谱分析,探讨岩溶陷落柱和围岩的雷达波频谱特征。岩溶陷落柱雷达波频谱呈现低频大振幅反射,其主频单一且突出;围岩雷达波呈现弱振幅多峰频谱,主频不突出。岩溶陷落柱和围岩雷达波频谱特征存在的显著差异,可作为识别岩溶陷落柱的重要依据之一。实践结果表明,地质雷达在探测岩溶陷落柱中具有有效性和实用性。

Taking collapse column under a tunnel as a example, ground penetrating radar （GPR） was used to detecting the target and the abnormal characteristics of the radar wave was analyzed, by which the location, scale and burial depth of the karst collapse column could be obtained accurately. Simultaneously, spectrum analysis was carried out in relation to the typical radar wave selected, through which the spectral characteristics of the radar wave as regards the karst collapse column and the surrounding rock was discussed. The spectrum of the radar wave as regards the karst collapse column presents low-frequency ＆ large-amplitude reflection with the dominant frequency single and prominent, while the spectrum of the radar wave as regards the surrounding rock low-amplitude ＆ multi-peak pattern with the dominant frequency less prominent. The notable difference between the two spectra may be taken as one of the important bases to identify karst collapse column. The practice result shows that GPR is an effective and practical means for the purpose of karst collapse column detection.