RaA氡气、甚低频测试在复核某电站库首变形体边界中的应用

Application of RaA radon and VLF methods in the deformation and fracture mass boundary test of a hydroelectric station

本文以西南某水电站库首右岸拉裂变形体为研究对象,根据现场的地形地貌,先从地质定性分析出发,初步确定拉裂变形体的上下游边界及前后缘边界。介于地质体的不均匀性及不可预见性,再在初步圈定的拉裂变形体上布置低线公路、高线便道以及纵线三条测线,通过RaA氡气、甚低频测试手段加以测试。最后在室内进行数据整理之后,作出各测点氡气值柱状图和甚低频视电阻率图,结合地质情况加以量化评判,结果表明与地质定性分析得出的边界情况基本吻合。可见,这两种测试手段为拉裂变形体的边界确定作出了较为充分的论证。

Taking example for the deformation and fracture mass at the right bank of a hydroelectric station in Southwest China, the upstream and downstream boundaries, the front and back boundaries of the deformation and fracture mass were determined using geological qualitative analysis of topography, geomorphology features first. Then, with the consideration of geological heterogeneity and unpredictability, we set three measuring sections at the lower road, higher pavement and vertical line respectively, using two ways of RaA radon and VLF（very low frequency method） to test the boundaries. After processing the data indoors, we got the radon value diagrams and the VLF apparent resistivity diagrams of each point. Based on the principles and geological conditions, we quantitatively identified analysis. It is obvious that the boundary sufficiently on the basis of these two test the boundaries agreed with those from geological qualitative determination of the deformation and fracture mass can be evaluated methods.