公路隧道坍塌灾害治理效果的GPR检测技术

以湖南省常吉高速公路度龙田隧道ZK 207+300~255坍塌地质灾害为例,详细地探讨了检测坍塌灾害治理效果的高精度地质雷达(GPR)检测技术。在综合分析和研究隧道坍塌灾害的基本情况及灾害治理措施的基础上,结合现场施工记录,采用GPR检测技术,准确地查清了塌方处理中注浆饱满度情况,检查了塌腔内是否仍存在危害隧道安全的空洞或松散体;同时,对塌方地段加密设置的钢拱架数量与间距也进行了准确的检测和判定。工程实践表明:结合隧道坍塌灾害相关资料及现场调查,GPR可以无损、快速、准确地检测隧道地质灾害治理效果和整治质量,为准确评价地质灾害治理效果提供科学依据,这对于减少工程隐患、确保工程质量、指导隧道施工具有重要的工程应用价值。

Technology of Detecting the Disposal Effect of Collapse Hazards in Road Tunnel by Using GPR System

Geological hazards without warnings such as roof collapse and mud-bursting are frequently encountered during the construction of tunnels under complex terrain and geological conditions,especially in the western mountainous areas of China. How to take efficient measures and reasonable technology to evaluate and detect the disposal effect of these geological hazards is very important to insure the quality of the project.This paper discusses in details the detection technology of detecting the collapse hazards in tunnel by Ground Penetrating Radar(GPR) through the case study of collapse hazards of Dulongtian-Tunnel(zk207+300～240) of Changde-Jishou Freeway in Hunan province.Based on the integrated analysis of the basic data collected and disposal measures,the detection technology of GPR can be used with local construction records to accurately detect the degree of saturation of the grout,the possibly existing cavities,and the number or space of the steel structure of reinforced shot Crete ring.A case study shows that GPR,combined by collected data,can not only detect the effect and quality of the disposal of the hazards without damage rapidly and exactly,but also offer scientific guide for the effect evaluation of the hazard disposals.All these are of practical values to reduce hidden hazards,insure the quality of construction and to provide guidance for the tunnel construction.