李家峡水电站大坝基础处理设计

李家峡三心圆双曲拱坝，坝高库大、坝基岩体中断层、层间挤压带、裂隙较发育，岩体完整性较差，主要地质问题有：左坝肩Ｆ２０上盘岩体稳定，边坡蠕动：河床Ｆ５０￣Ｆ２０之间岩旬度较低可能渗漏：左岸Ｆ２４、右岸Ｆ２７岩体；及某些局部渗漏问题，在设计中进行了坝肩抗滑稳定、变形稳定分析研究，采取了一些常规处理和特殊处理措施。经处理后，两坝肩抗滑安全度满足规范要求；坝基变形特征有了改善；左Ｆ２６、ｆ２０，右Ｆ２７能

Design of dam foundation treatment in Lijiaxia Hydropower Station

The Double curvature arch dam with three centers for Lijiaxia Hydropower Station is a high dam and large reservoir. In the rocks of the dam foundation,the fault,interlayer crushed zone and fissures are developed with a poor completion of rock.The main geological problems are as follows.The upper wall of F 20 rock in the left dam abutment is stable but its side is creeping.The rigidity of the rocks among F 50 ,F 20 1 ,and F 20 in the river bed is relatively low which seepage may be occurred.The rock bodies of F 26 in the left bank and F 27 in the right bank are stable.And some local seepages exist. In the design,the study and analysis on the stability against sliding in the abutments and deformation have been conducted and some conventional and special treatments have been made.After treatment,the safety of stability against sliding in the abutments could meet the requirements of national standards.The feature of deformation in the dam foundation has been improved.The rock bodies of F 26 and F 20 in the left abutment and F 17 in the right abutment could meet the requirements of stability. The safety coefficient of the monolithic stability of the dam and its foundation is more than 3 0.