探地雷达在输电线路塔基地下空洞检测中的应用

利用探地雷达技术原理，选用AB-50MHz非屏蔽蛇形天线、AB-150MHz和AB-250MHz屏蔽天线，对220kV输电线路塔基附近的人工模拟地下空洞模型进行检测。结果表明：AB-50MHz非屏蔽天线和AB—150MHz屏蔽天线均能检测到空洞，而AB-250MHz屏蔽天线则不能检测到空洞；空洞的图像特征为明显的弧形异常反射，AB-150MHz屏蔽天线检测效果优于AB-50MHz非屏蔽天线。对以上检测结果进行原因分析，并就输电线路塔基地下异常体检测方法提出建议。

Application of Ground Penetrating Radar on Detection of Subsurface Cavity in Transmission Line Tower Foundation

In this paper, AB-50 MHz unscreened antenna, AB-150 MHz and AB-250 MHz screened antenna were selected and the artificial simulated subsurface cavitiy near the base of 220 kV power transmission tower was detected by means of ground penetrating radar. The results showed that the the cavity could be detected by both AB-50 MHz unscreened antenna and AB-150 MHz screened antenna, except AB-250 MHz screened antenna. The digital image feature of cavitiy was curverd abnormal reflections obviously, and the effect of detection with AB-150 MHz screened antenna was better than the AB-50 MHz unscreened antenna. Moreover the detection results were analyzed, and the proposal about detection method of transmission line tower foundation underground anomaly was made.