浅论柴石滩水库坝址区工程地质问题及工程处理

Discussion on Engineering Geological Problems in Damsite of Chaishitan Reservoir Complex and Their Engineering Treatment

坝址区为一单斜构造，岩层走向NNE，倾向NW，倾角40°，坝基构造主要受上游三湾～松子园大断层和下游柴石滩大断层的影响，坝基断裂发育，层间挤压现象明显，左岸构造风化破碎带突出且深厚。由于存在断裂、构造风化破碎带、层间软弱夹层、岩溶管道、卸荷裂隙等不良地质现象，使左岸存在渗漏，渗流失稳，右岸溢洪道高边坡上部不稳定和发电洞、灌溉洞出口边坡稳定性等工程地质问题，对工程施工处理造成影响和难度，因此，笔者对该问题进行浅论和提出工程处理建议。

The damsite area is of geologically a uniclinal structure with rock formation striking NNE, dipping NW at anangle of 40°. The structure of the dam foundation is mainly affected by its upstream Sanwan-Songziyin large fault and itsdownstream Chaishitan large fault. The dam foundatiun has developed fractures and significan interbedding compressiongeologically. The structural weathering fractured zone is deep and thick on the left bank. The existence of faults, structuralweathering fractured zone, interbedding soft seams, solution conduits and stress-released fissures causes seepage andseepage instability on the left bank. The instable upper part of the right bank spillway, and the slope stability at the existsof the powr tunnel and the irrigation toel hring ab0ut difficulties to the constructim treatment of the project .Theauthor has a discussion we these problefns and Inakes proposals on engineering treatment.