黄土斜坡优先流促滑机理研究现状及展望

目的]对斜坡中因节理、裂隙、孔洞等优势通道的存在而发育的优先流所产生的促滑效应研究现状进行总结,以期引起学者重视优先流理论在斜坡地质灾害研究中的应用,为准确开展滑坡预测预警提供科学依据。方法]从优先流的定义与类型出发,分析了优先流的众多影响因素,重点综述和评价了优先流对斜坡稳定性的影响、斜坡优先流探测技术以及稳定性评价模型方面的研究现状,总结了黄土斜坡优先流促滑致灾的4个发展阶段,并以典型滑坡作为实证,最后分析了优先流促滑作用机理研究中存在的问题。结果]黄土斜坡优势渗流通道中普遍发育的优先流是有限降雨影响深度条件下斜坡失稳的合理解释,然而,优先流在滑坡致灾规律理论及应用上仍需更多实践检验。结论]斜坡优先流是斜坡水文学、非饱和土力学、地质灾害学等相关学科方面一项重要的理论,多年来已取得不少成果,今后还需继续深入开展黄土斜坡优先流促滑效应研究,加强多学科交叉和新技术应用,来提高地质灾害科学预测与防治水平。

Current Status and Prospects of Research on Mechanism of Preferential Flow-induced Sliding in Loess Slope

Objective] Summary and review of the research status on the preferential flow-induced sliding effects developed by the existence of dominant channels such as joints, fissures and holes in the slope were conducted, in order to draw the attention of scholars to the application of preferential flow theory in the study of slope geological hazards and provide scientific basis for accurate forecasting and early warning of landslides. Methods] According to the definition and types of preferential flow, the influential factors of preferential flow were analyzed, and the current status of the influence of preferential flow on slope stability, the preferential flow detection technology and the stability evaluation model of slope were reviewed and evaluated emphatically. The developing process of preferential flow-induced landslide effect on loess slope was summarized as four stages, and the typical landslides were taken as examples. Finally, the issues of the preferential flow-induced sliding mechanism were clarified. Results] The preferential flow widely developed in the dominant seepage channels of the loess slope is a reasonable explanation for slope instability under the condition of limited rainfall depth. However, the theory and application of preferential flow in landslide hazards prediction still need more practical tests. Conclusion] Slope preferential flow is an important theory in hillslope hydrology, unsaturated soil mechanics, geo-hazards science and other related disciplines. Many achievements have been made over the years. In the future, it is necessary to further study the effect of preferential flow-induced sliding on loess slopes, and strengthen the application of multidisciplinary and new technologies to improve the level on scientific prediction and prevention of geo-hazards.