深厚覆盖层土石围堰悬挂式防渗墙参数优化设计

Design Optimization of Suspended Cut-off Wall Parameter of a Rockfill Cofferdam on Deep Overburden Layer

深厚覆盖层中的悬挂式防渗墙高度对土石围堰渗流特征起到重要作用。综合考虑围堰施工工期、经济性及安全性,借助有限元法对深厚覆盖层土石围堰悬挂式防渗墙的合理设计高度进行了探讨,系统分析了不同工况下悬挂式防渗墙高度对围堰渗流特征的影响规律,在此基础上探讨了上游不同水位高程对围堰渗流特征的影响。结果表明,悬挂式防渗墙设计高度50 m时渗流参数最优,具有可行性,但随着上游水位升高,应注意采取适当措施进行渗流控制。

The height of suspended cut-off wall in deep overburden layer plays an important role in controlling the seepage stability of rockfill cofferdam.Considering the construction period,economy and safety of the cofferdam,the reasonable design height of the suspended cut-off wall is discussed based on finite element numerical simulation,and the influences of cut-off wall height on seepage stability of cofferdam under different operation conditions are analyzed.In addition,the influence of different upstream water levels on cofferdam seepage characteristics is further discussed.The results show that,when the design height of the suspended cut-off wall is 50 m,the seepage characteristics are optimal,but with the rise of upstream water level,appropriate measures should be taken to control the seepage.