《Journal of Geomechanics》杂志刊登“评估潜在的渗流诱导来解开水流流过堆石坝而导致的失事”

作者：David Hansen and Ali Roshanfekr

刊物：《Journal of Geomechanics》，2012年，12卷第5期，560-573页

关键词：渗流模型；粗填石；失事原因揭示；初始流动；过流堤防

摘要：进行了24个水流流过堆石坝的几何外形的一个纯粹的数值参数的研究。利用有限差分法处理了一个非线性的像p-LaPlacian算子的偏微分方程，有限差分法直接合并的一个幂律指数来代替达西定律。收敛，使用特定的节点，节点密度和边界条件影响进行定量。发现脚趾的流场角在研究解开失事原因方面是一个很有效的起始点。对应一系列下游的斜坡展示了这种失事的安全因数，显示了哪些斜坡和粒径的组合是不安全的。结果表明安全因数FS在渗流面下结合处降低，一是因为在结构的脚趾处出口的强度梯度，二是因为溢流速度。希望展示的技术和成果会方便设计和评估通过堆石结构的流量。

Assessment of Potential for Seepage-Induced Unraveling

Failure of Flow-Through Rockfill Dams

Authors: David Hansen and Ali Roshanfekr

Journal: Journal of Geomechanics, Volume 12, Number 5 (2012), 560-573

Key words:Seepage modeling; Coarse rockfill; Unraveling failure; Initiation of motion;.

Abstract:Apurelynumericalparametricstudyof24flow-throughrockfildamgeometrieswasconducted.Thenonlinearnatureofthep-LaPlacian–like partial differential equation was dealt with using a finite-difference scheme that directly incorporated the exponent of a power law thatreplaced Darcy’s law. Convergence, use of specialty nodes, nodal density, and boundary condition effects were quantitatively investigated.The flow-field angle of the toe was found to be a useful starting point in studying the potential for unraveling failure. Factors of safety (FS) againstthistypeoffailurearethenpresentedforarangeofdownstreamslopes,thusshowingwhichcombinationsofslopeandparticlediameterareunsafe.ItisshownthattheFStendstodropbelowunityundertheseepagefaceprimarilybecauseofthestrengthoftheexitgradientnearthetoeofthe structure and secondarily because of the overflow velocity. It is hoped that the techniques and results presented will facilitate the design andassessment of flow-through rockfill structures.

原文链接：http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GM.1943-5622.0000145