探地雷达在堆石坝组合防渗体检测中的应用研究

Application of ground penetrating radar in the detection of combined seepage prevention body of rockfill dam

堆石坝组合防渗体作为隐蔽结构,无法直接观测,存在安全隐患。本文基于探地雷达方法,对某爆破堆石坝组合防渗体结构进行探测分析,并对混凝土面板下部的脱空、渗漏等缺陷的典型雷达图像进行分析。在将组合防渗体结构与探地雷达图像特征波形进行对应的基础上,结合堆石坝结构破坏特点,确定大坝可能渗漏的部位并进行成因分析。对于不宜开挖验证区域,通过分析坝体内部渗压计监测资料,对探地雷达法无损检测结果提供验证。结果表明:探地雷达在大坝组合防渗体及内部缺陷检测中有较好的可行性,其检测结果能为大坝后续除险加固等工程提供可靠的支持,对确保工程安全具有重要意义。

As a concealed structure,the combined seepage prevention body of the rockfill dam cannot be directly observed,and there are hidden safety hazards.Based on the ground penetrating radar method,this paper detects and analyzes the structure of the combined seepage prevention body of a blasting rockfill dam and analyzes the typical radar images of the defects such as void and leakage under the concrete face slab.On the basis of correspondence between the structure of combined seepage prevention body and the characteristic waveform of ground penetrating radar image,combined with the failure characteristics of rockfill dam structure,the possible leakage location of the dam is determined with the causes analyzed.For areas that are not suitable for excavation and verification,the results of the ground penetrating radar method for nondestructive testing are verified by analyzing the monitoring data of the osmometer inside the dam.The results show that the ground penetrating radar has good feasibility in the detection of dam combined seepage prevention body and internal defects,and that its detection results can provide reliable support for subsequent dam reinforcement projects,which is of great significance in ensuring engineering safety.