为了在隧道工程中准确应用探地雷达进行超前预报,针对可能遇到的常见干扰和典型不良地质体,探讨了常见干扰的成因及其对资料解译的影响,确定常见的干扰剖面图,并分别对天线耦合干扰和金属物干扰进行举例分析,提出探地雷达在采集数据过程中避开干扰的注意事项。列举3个工程实例,分别介绍了探地雷达对溶洞、断层裂隙水、软弱夹层等不良地质体的预报研究,通过分析其典型雷达剖面图的波形、频率、振幅等特征,依此推断出隧道开挖掌子面前方潜在不良地质体的类型以及位置、构造走向等空间分布特征。该结果与实际开挖揭示的不良地质体的分布范围基本一致,验证了探地雷达在预报隧道常见不良地质体的可行性和有效性。通过总结分析常见雷达干扰图像和典型不良地质体剖面图,有助于物探工作者对复杂地质体进行更精确地解释,确保隧道施工安全。

In order to apply ground penetrating radar(GPR) to accurate advanced geological prediction in tunnel engineering, we discussed the causes of common interferences and their influences on data interpretation, and determined the reflected interference information in profile of GPR image. Then, we gave examples of the antenna coupling and metal interferences and put forward precautions to avoid interference in the process of collecting GPR data. On the basis of three examples, we introduced the prediction of bad geological bodies such as karst cave, fault fissure water, and weak interlayer. Through analyzing typical characteristics of waveform, frequency and amplitude of the profile, we predicted the type of bad geological body as well as the spatial distribution characteristics like location and structure strike ahead of the working face of the tunnel. The prediction results are basically consistent with the distribution of bad geological bodies revealed by excavation, which proves that GPR is feasible and effective in the prediction of common bad geological bodies. By summarizing and analyzing the common radar interference images and the profiles of GPR images of typical geological bodies, we can provide references of interpreting complex geological bodies more precisely for geophysical workers and ensure the safety of tunnel construction.