黄土高原小流域重力侵蚀稳定性评价  

Stability Evaluation of Gravitational Erosion for Small Watershed on the Loess Plateau

作　　者：张霞 张振文 李占斌[2,3] 于国强[4] 

机构地区：[1]陕西省环境科学研究院,陕西西安710061 [2]西安理工大学西北水资源与环境生态教育部重点实验室,陕西西安710048 [3]中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100 [4]中国地质调查局西安地质调查中心,陕西西安710054

出　　处：《水土保持通报》2012年第3期236-239,301,共4页Bulletin of Soil and Water Conservation

基　　金：中国博士后基金项目"白龙江流域暴雨泥石流运动机理及数值模型研究"(2011M501445);国家自然科学基金项目"矿渣型泥石流起动机理及临界参数研究"(40872208);国家自然科学基金项目"基于小流域淤积信息的侵蚀产沙与侵蚀环境变化响应研究"(40971161)

摘　　要：为评价黄土高原小流域重力侵蚀稳定性,采用有限差分FLAC3D软件对黄土高原王茂沟小流域概化模型进行了研究。对小流域平衡状态时位移场和应力场和塑性屈服区进行数值模拟,并结合Rosen-blueth矩估计方法对流域重力侵蚀破坏概率可靠度进行了分析。结果表明,剪切塑性区域主要分布于坡面和沟坡大部分区域,张拉塑性区域主要分布于梁峁顶和梁峁坡上部;该流域重力侵蚀处于不可接受的风险水平,需采取有效的工程措施以提高其稳定性。Rosenblueth法可有效地将传统安全系数与概率分布相互结合补充,为建立流域稳定性与重力侵蚀可靠度的指标评价体系提供了一种好的方法。To evaluate the stability of gravitational erosion for small watershed on the Loess Plateau,the conceptual model of Wangmaogou watershed is explored with the aid of the finite difference software,Flac3D,and the numerical simulations for stress field,displacement field and plastic yielded zone are made as the watershed system is in balance.The reliability is analyzed for the failure probability of gravitational erosion,combined with Rosenblueth moment estimation method.Results show that.The shear plastic zone is greatly located in the most area of slope and gully slope,and the tension plastic zone is mainly located on top and slope of barren hill.The gravitational erosion of watershed is in unaccepted risk level and effective engineering measures should be taken to improve its stability.Rosenblueth moment estimation method can effectively combine the conventional safety factor with probability distribution,which may offer a better approach to the building of evaluation index system for watershed stability and gravitational erosion reliability.

关 键 词：重力侵蚀 流域稳定性 Rosenblueth矩估计方法 可靠度指标 

分 类 号：S157.1[农业科学—土壤学]