探地雷达的常见干扰和不良地质体的超前预报在隧道工程中的应用

Common Interferences of Ground Penetrating Radar and Advanced Prediction of Bad Geological Bodies in Tunnel Engineering

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 geologengineering, we discussed the causes of common interferences and their influences on data interpretation, anddetermined the reflected inte r fe renc e information in profile of G PR im ag e. T h e n, we gave exampcoupling and metal inte r fe renc e s an d p u t forward p rec au t io n s to avoid in te r fe ren c e in data. On the bas is of th re e e x amp le s, we in tro d u c ed th e p red ic tio n of b ad geological bodie s such fissure water , and weak inter layer. Through analyzing typic al ch a ra c te r is t ic s of waveform , freq u en cyof the profile , we predicted th e type of b ad geological body as well as th e sp a tia l d is trib u t io n ch a ra c te r is t ic s l ik e lo-cation and structure str ike ahe ad of th e working fac e of th e tu n n e l. The p red ic tio n re su lts a re bas ica lly cons istentwith the distribution of b ad geological bodie s reve aled by ex c av a t io n, which proves th a t G PR itive in the prediction of common b ad geological b o d ie s. By summarizing an d analyzing th e common ra d a r in te r fe r-ence images and the profiles of GPR images of ty p ic al geological b o d ie s, we can provide referen c es of in te rp re tin g complex geological bodies more p re c ise ly for geophys ical workers an d en su re th e saf