堤基渗流破坏影响因素试验研究及数值模拟

Experimental research and numerical simulation on influence factors of piping development in levee foundation

堤基防渗处理多采用"前截中压后排"的方法,通过砂槽模型试验研究,分析覆盖层模拟方式、压盖重量、悬挂式防渗墙、渗流出口型式等工程因素对渗流破坏的影响,并采用流体动力学有限体积方法对试验工况进行了数值模拟分析。研究表明覆盖层的试验模拟方式对渗流破坏坡降有较大影响,应结合工程实际选择合理的模拟方式;压重增加可以提高渗流破坏的临界坡降;悬挂式防渗墙对阻止渗流变形的发生作用较小但可以延长渗径,提高承担水头,;渗流出口进行反滤处理后防渗能力有很大提高。研究成果与工程实际符合,为堤防防渗加固和防洪决策提供参考。数值模拟结果与试验数据接近,为进一步模拟研究渗流破坏过程和各种工况的防渗效果提供了基础。

In order to prevent seepage of levee foundation,reinforcement measures are usually made up of cut-off walls, counterweight filling,drainage structure.Analysis on the influence factors of piping development by using flume model tests and the finite volume method in CFD.The factors include conformation of the covering layer,weight of counterweight filling, depth of suspended cut off walls,drainage structure in seepage export,et al.The experimental and numerical results agree with the practical situations and can be the reference for the reinforcement measures.The numerical simulation results agree well with experimental data.The numerical method can be the basis of further research of piping development.