黄河山坪电站船闸地基渗控措施优化

建立黄河山坪电站船闸地基的有限元模型,采用有限单元法研究三维渗流场,对计算得到的水头、扬压力、渗透坡降以及渗透体积力等进行分析.针对防渗墙的防渗作用,讨论墙厚及墙体嵌入基岩深度的敏感性,为防渗墙优化设计提供参考.结果表明:设置防渗墙后,有效地降低了闸底板的扬压力,提高了地基的渗透稳定性;墙厚的变化,对墙体的渗透坡降有较大影响;墙底基岩的渗透坡降随墙体嵌入深度的增大而减小;设计院采用的防渗墙厚度60cm、嵌入基岩深度1m的方案是合理且经济的.此外,通过三维渗流场分析得到的渗透体积力,可为进一步研究地基应力、沉降变形、抗滑稳定以及在地震作用下含泥粉细砂可能发生的震动液化提供渗流荷载依据.

Seepage control measure optimization for Shanping ship lock foundation in Yellow River

Finite element model of Shanping ship lock foundation at the Yellow River is established;and the three-dimensional seepage field is researched with finite element method,in order to analyze the head,uplift,seepage gradient and permeating volume strength.In view of the role of the cut-off wall,the sensitivity analysis of the thickness and embedding bedrock depth is researched to provide a reference for the cut-off wall optimization design.The results show that the layout of the cut-off wall reduces floor uplift effectively and contributes to foundation seepage stability.Variation of the wall thickness has a great influence on wall seepage gradient;while the bedrock gradient decreases with the embedding depth increasing.The scheme that the wall thickness is 60 cm and embedding bedrock depth is 1m,adopted by design Institute,is reasonable and economical.Besides,the permeating volume strength,obtained by analyzing three-dimensional seepage field,so as to provide the basis of seepage load for the further research of foundation stress,settlement deformation,anti-sliding stability and seismic liquefaction,which is likely to occur in clay fine sand under seismic action.