The Research On Application Of Dam Impervious Wall Detection Based On Double Array Electrical Prospecting System

Our country is rich in water resource,in order to make full use of water resources,people built dams in the river upstream,for the use of hydroelectric power and water source.But the river in the benefit of mankind at the same time,it will also bring disaster to mankind.During the annual flood season,the water level in the river will rise rapidly due to the increase of precipitation,more than a safe water level or the destruction of the dam,which will bring huge floods to the people along the coast.Flood disaster occurred in 1998,resulting in a lot of disrepair dam leakage or even dam break,to the people's lives and property safety and the national economy caused a major threat and loss.After that,the state increased the strength of the river dam reinforcement.In order to resist the flood disaster,the dam project is built along the river,in order to improve the ability of the dam to resist flood and protect the safety of the dam,the impervious wall is built along the dam.The quality of the cutoff wall will directly affect the stability of the dam,the leak point detection of impervious wall is an important link to ensure the safety of impervious wall and even dam,there is no fast and effective way to detect the wall now.This paper designs a set of system which is specially designed for the detection of impervious wall,double row high density resistivity observation system,referred to as DHR detection system.This system was used to detect the cutoff wall,symmetrically arranged on both sides of the impervious wall along the electrode side emission current supply to the underground,and measured on the other side,according to the calculation of the resistivity change of electric field measured,further analysis of the integrity of the inference of impervious wall.DHR detection system includes two kinds of observation,which are DHR-2P and DHR-4P.The physical simulation test of two kinds of detection methods in the laboratory is carried out.The results show that the DHR detection system is effective,and can accurately locate the location and distribution of the hidden danger.Because other methods are in the single side of impervious wall,so the hidden danger is not obvious,or even detect the existence of hidden dangers.The design of DHR detection system applied to a section of Songhua River to detect the wall.Through the testing of the test section,DHR-2P and DHR-4P can effectively detect the location and depth of the cutoff wall.On this basis,the range of resistivity values of the integrity section of the cutoff wall is determined,and a large area of testing work is carried out.The cutoff wall about 30 kilometers of Songhua River embankment has been effectively detected,and good results have been achieved.Through laboratory tests and engineering practice,it is indicated that the DHR detection system can be used to evaluate the quality of impervious wall,and can be used in Water conservancy project.