宝珠寺水电站坝基排水孔异常逸出物成因分析

Analysis of the formation of abnormal substances discharged from drainage well in Bao-zhu-si dam base

阐述了宝珠寺水电站坝基排水孔异常逸出物的化学成分及矿物成分 ,重点分析了坝基排水孔地下水的补给来源、排出水的化学成分特征、地层岩石与大坝建筑材料的化学与矿物成分、异常逸出物的成因等。结果表明 ,宝珠寺水电站坝基排水孔异常逸出物是补给水由补给源运移至坝基排水孔过程中与地层岩石、大坝建筑材料相互作用而形成的 ,其中石英、方解石、白云石、钠长石和微斜长石的沉淀作用、羟钙石和石膏的溶解作用以及SO2 -4 被地层岩石中的有机物质还原为H2 S是最重要的几种作用。

This article discussed the chemical and mineral composition of the abnormal substances discharged from drainage well in Bao-zhu-si dam base. The detailed analysis came to the following parts: (1) the origin of the discharged groundwater. (2) the characteristics of the composition of the discharged groundwater. (3) the chemical and mineral composition of dam base rock and construction materials. (4) the process of the formation of the abnormal substances. Results showed that the abnormal substances are formed by interactions between groundwater and dam base rock as well as construction materials of the dam. Among these the precipitation of quarts, calcite, dolomite, albite, plagioclase, the dissolution of hydroxy calcium oxide and gypsum as well as the deoxidization of SO~ 2- 4 to H 2S by organic materials are the most important reactions.