地质雷达在公路隧道超前地质预报中的应用

Application of Ground Penetrating Radar to Geological Forecast for Expressway Tunnel Construction

首先,介绍了地质雷达的工作原理及其探测方案和探测技术参数的确定原则。其次,采用瑞典MALA公司的RAMAC/GPR通用型主机CUⅡ,同时结合掌子面地质素描,对某高速公路的3条隧道进行超前地质预报。根据现场工作条件及探测精度和深度的要求,测线布置采用"十"形测线,测量方式采用点测方式,测点间距为20 cm,天线中心频率主要采用100 MHz。结果表明,采用该方法对断层、溶洞、含水裂隙和软弱夹层等不良地质状况的预测基本符合掘进实际,保证了施工安全、加快了工程进度,同时为地质雷达在公路隧道超前地质预报中的应用积累了一些经验。

First, the working principle of ground penetrating radar （GPR） and the method to confirm the technical parameters are introduced.Second, the geological conditions of 3 tunnels of an expressway are forecasted by using CUll ground penetrating radar and geological sketch method. Cross survey line, point data collection at 20 cm intervals and antenna of 100MHz are used according to the working condition, the accuracy and depth requirement.The results show that the forecast of fault fracture, limestone cave, fissure and feeble stratum fit the reality.The accurate prediction guaranteed safe production, accelerated job schedule and acquired favorable benefit. Some experience about the application of GPR to geological forecast is obtained.