深基坑应急工程中的雷达检测技术研究与应用

Research of GPR Checking Technology in Emergency Engineering for Deep Foundation Pit and Its Application

在深基坑工程事故中,地基土既是结构变形导致事故的重要载体,又是事故的直接承受体。作为应急抢险常用的注浆方法,其工程效果主要取决于对土层变形的了解程度及浆液的影响范围和固结程度。因此,查明土体变形是预防和治理深基坑工程事故的前提,检测浆液分布则是确保应急处理质量和进一步采取补救措施的手段与依据。本文以某办公大楼和某酒店深基坑工程的土层变形及止水加固压密注浆的雷达探测为例,阐述了探地雷达原理、技术特点及工作方法。两个工程实例表明,作为一种快速实用的无损检测技术,雷达探测结果可用于指导应急注浆工程的实施,特别是某酒店深基坑工程中,以浆液分布情况的雷达探测结果为依据进行补救注浆达到了较好的止水目的。

For the accident in deep foundation pit engineering,the structure deformation of foundation soil is not only the important cause of accident,but also its bearer.The effect of Compact grouting method,commonly used for emergency treatment,lies on the soil deforming situation,the distributing range（into the soil） and concretion rate of slurry.So the precondition for preventing and treating the accident in deep foundation pit engineering is to detect the soil deformation.And to detect the slurry distribution is one important measure and basis for ensuring treatment quality and further remedial measure.This paper described principle,technology character of GPR and practical working method.And two examples for testing soil deformation,reinforcement and waterproof of one office building and one restaurant deep foundation pit are presented.The examples demonstrated that GPR is a fast non-destructive testing technology,and the testing results can be used to guide emergency compact grouting engineering.