摘要
为了研究悬挂式防渗墙在堤基管涌发展过程中的控制作用机制,该文采用了基于管流-渗流耦合方法的管涌动态发展数值模型,选取二元堤基条件,模拟了管涌通道在堤基无墙情况和设置悬挂式防渗墙情况下的管涌动态发展过程。数值结果表明:悬挂式防渗墙对渗流场的影响是有限的,仅其周围局部区域的流场会因防渗墙发生显著改变,该区域外的流场变化则不大。悬挂式防渗墙将管涌通道的发展过程分为下游侧发展段、绕墙段和上游侧发展段等3个阶段,其中绕墙段的发展耗时明显大于其他阶段。在管涌通道绕墙段的发展中,由于局部流场的改变,土颗粒侵蚀的水动力学条件降低;同时由于管涌发展方向改变,土颗粒的自重增加了颗粒侵蚀的阻力,提高了颗粒侵蚀临界起动条件,使侵蚀难以继续发展。
Suspended cut off walls in levees can control the piping progression in a levee foundation. A piping development model was developed by coupling the seepage-piping flow domains. Simulations show that the influence of the cut off wall on the seepage field is limited and only strongly affects the neighbouring seepage field with little effect on seepage fields far from the wall. The suspended cut-off wall divided the piping progression into a downstream stage, a getting over the cut off wall stage and the upstream stage. The getting-over stage consumed much more time than the other stages. When the piping was getting-over the cut off wall, the hydrodynamic conditions of the soil erosion were lowered by the weaker seepage field. Meanwhile, since the development direction of the piping was changed by the cut off wall, the self-weight of the soil particles increased the erosion resistance, while enhanced the critical condition for soil particle motion inception.
出处
《清华大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2015年第2期164-169,共6页
Journal of Tsinghua University(Science and Technology)
基金
"十二五"国家科技支撑计划资助项目(2012BAB02B02)
关键词
悬挂式防渗墙
管涌
堤基
suspended cut-off wall
piping
levee foundation
