对于有断层带存在的坝基, 其防渗帷幕和密集排水孔幕的效果是水利水电工程安全的关键问题之一。针对伊江上游某重力坝基础, 利用三维渗流场有限元精细求解技术, 建立了伊江上游某坝基渗流场计算模型, 分析了断层带范围内防渗帷幕失效和坝基排水孔不同间距条件下的渗控效果。成果表明断层带范围内防渗帷幕失效, 坝基渗流量增大, 但扬压力折减系数仍满足设计要求;排水孔幕间距扩大1倍, 渗控效果并无明显变化。成果可为类似坝基渗控设计提供参考依据。
The effect of impervious curtain and intensive drainage holes in the dam foundation with fault is a key problem in hydro-electric engineering. By employing three-dimensional finite element, a seepage model is proposed with a gravity dam foundation in the upstream of Irrawaddy River as case study. The seepage control effect in the presence of failed impervious curtain or different spacings of drainage holes is analyzed. Results indicated that when the impervious curtain in the fault failed, the discharge increased but the reduction coefficient of uplift pressure met the design requirement; and when the spacing between drainage holes doubles, the seepage control effect did not change significantly. The research result could be a reference for similar designs of seepage control for dam foundation.
[1] 速宝玉, 朱岳明. 不变网格确定渗流自由面的节点虚流量法[J]. 河海大学学报, 1991, 19(5): 113-117.(SU Bao-yu, ZHU Yue-ming. Procedure of Node Virtual Flux for Seepage Free Surface with Fixed Mesh[J]. Journal of Hohai University, 1991, 19(5):113-117. (in Chinese))
[2] 崔皓东, 朱岳明. 有自由面渗流分析的改进节点虚流量法[J].武汉理工大学学报, 2009, 33(2):238-241. (CUI Hao-dong, ZHU Yue-ming. The Improved Procedure of Nodal Virtual Flux of Global Iteration to Solve Seepage Free Surface[J]. Journal of Wuhan University of Technology, 2009, 33(2):238-241. (in Chinese))
[3] 崔皓东, 朱岳明, 吴世勇. 有自由面渗流分析的密集排水孔幕数值模拟分析[J]. 岩土工程学报, 2008, 30(3):440-444. (CUI Hao-dong, ZHU Yue-ming, WU Shi-yong. Numerical Simulation for the Densely-distributed Drainage Holes in Seepage with Free Surface[J]. Chinese Journal of Geotechnical Engineering, 2008, 30(3): 440-444. (in Chinese))
[4] DL 5077—1997, 水工建筑物荷载设计规范[S].北京:中国电力出版社, 1998.(DL 5077—1997, Specifications for Load Design of Hydraulic Structure[S].Beijing: China Electric Power Press, 1998.(in Chinese))
[5] 朱岳明. Darcy渗流量计算的等效节点流量法[J]. 河海大学学报(自然科学版), 1997, 25(4): 105-108. (ZHU Yue-ming. Darcy Seepage Discharge Calculation with Node Method[J]. Journal of Hohai University, 1997, 25(4):105-108.(in Chinese))
[6] 崔皓东, 朱岳明, 张家发, 等. 深埋洞室群围岩渗流场分析及渗控效果初步评价[J].长江科学院院报, 2009, 26(10):71-75. (CUI Hao-dong, ZHU Yue-ming, ZHANG Jia-fa, et al. Analysis on Seepage Field and Preliminary Evaluation on Seepage Control Effect of Rockmass around Deep Buried Caverns[J]. Journal of Yangtze River Scientific Research Institute, 2009, 26(10):71-75. (in Chinese))
