The purpose of this study was to model landslide occurrence (LO) in the hilly areas of Bududa District taking to consideration the effect of commonly known causative factors and an uncommon landslide causal factor of wind forces on slope with eucalyptus trees. Five different slope models, without and with additional shear strength infrom of tree root cohesion have been use to obtain the final results of LO, with all subjected six (6) different failure criteria (FC). The first four failure criteria (FC1, FC2, FC3 and FC4) assumed were for; group of trees on the slope, tree at the top, tree in the middle and tree at the toe of the slope , while FC5 and FC6 were for slope models with rainfall infiltration only and rainfall plus group of tree weight respectively. Beaufort wind scale 11 was used, and Tree Diameters at Breast Heights (DBH) were varied, commencing with 25cm, 30cm and 60cm for assumed eucalyptus tree height of 25cm. The additional shear strength due to an increased cohesion from the roots ( was assumed, on the top soil layer of silty clay. Finite element analysis with SEEP/W 2007 was coupled with Limit equilibrium analysis software of SLOPE/W 2007 to achieve expected output or results from different failure criteria. Initial suction of 50kPa at the top of silty clay and 20kPa in the layer of silty gravel, with a total 1044 generated deformed mesh boundary condition were used in transient seepage analysis. Slope model 1 with eucalyptus trees of DBH 25cm yielded an output minimum factor of safety (FOS) of 1.012 for FC3 and value of 1.253 for FC3 (an increase of 23.81% from slope model 4), without and with increased cohesion respectively. With DBH increased to a maximum of 60cm, for slope model 3, safety of the community around this site diminished as the FoS reduced to 0.562 with FC2 and 0.601 with FC3 on day 25, without cohesion, just hours before the fateful day on the 26th June 2012 and remained below 1.0 (from 0.601 to 0.800) with FC3 with roots cohesion, although a gain in the FoS of 33.11% was realized.
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机译：这项研究的目的是在考虑到普遍已知的致病因素和风力不常见的滑坡成因因素对桉树坡度的影响时，对布达达地区丘陵地区的滑坡发生（LO）进行建模。已经使用了五种不同的坡度模型，没有或没有附加的抗剪强度，获得了LO的最终结果，所有模型都经历了六（6）个不同的破坏准则（FC）。假定的前四个故障标准（FC1，FC2，FC3和FC4）用于；斜坡上的树组，顶部的树，中间的树和树的脚趾树，而FC5和FC6分别是仅降雨入渗和降雨加树重的斜坡模型。使用Beaufort风标尺11，并且改变了乳房高处的树径（DBH），从25cm，30cm和60cm开始，假定的桉树高度为25cm。由于从根部增加了内聚力，因此产生了额外的剪切强度（假定是在粉质粘土的表层土层。SEEP/ W 2007的有限元分析与SLOPE / W 2007的极限平衡分析软件结合使用，可以达到预期的产量或瞬态渗流分析采用了粉质粘土顶部的初始吸力为50kPa，粉质砾石层的初始吸力为20kPa，共产生了1044个变形网格边界条件；坡度模型1为DBH 25cm的桉树在不增加和增加内聚力的情况下，FC3的最小输出安全系数（FOS）为1.012，FC3的最小输出安全系数为1.253（与坡度模型4相比增加了23.81％）。模型3中，该站点周围社区的安全性降低，因为在2012年6月26日这一重要日子之前的第25天，FC2的FoS降至0.562，FC3的FOS降至0.601，没有凝聚力，并且仍然存在在具有根凝聚力的FC3的情况下低于1.0（从0.601到0.800），尽管实现了33.11％的FoS增长。
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