Detection of Leakage in Earth-rock Dam using High Density Resistivity Method

High density resistivity method is a new geological survey technology based on the normal resistivity survey method. The method not only allows us to collect large amount of data and information during field work, but also has high resolutions in surveyed planes or areas. The high density resistivity method has been widely used in detecting leakage in earth-rock darn since it is an efficient and advanced non-destructive detection technology. The situation of engineering application of high density resistivity method in our country is introduced in this paper, and the detected results for leakage checking of two typical reservoir dams are also presented as case studies to illustrate the theory and advantages of this method. Through the analysis of results and comparisons with the on-site leakage observations, some conclusions are drawn as follow: 1. The detected location of leakage using high density resistivity method is almost the same saturated location observed on-site survey. The leakage passage is conjectured to be at a low elevation position in the downstream of reservoir dam. 2. There is a large low resistivity area in the right bank of Qiarang Reserovir dam where the leakage passage is conjectured Both detection results of two reservoir earth-rock dams indicate that the high density resistivity method is efficient and reliable to detect leakage locations, i.e. low resistivity areas. Therefore, the high density resistivity method for leakage detection in earth-rock dam is recommended since it has many advantages in survey.