Experimental tests of slope failure due to rainfalls using 1g physical slope models
Experimental tests of slope failure due to rainfalls using 1g physical slope models
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DOI：
10.1016/j.sandf.2018.02.003
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发表时间：
2018-04-01
影响因子：
3.7
通讯作者：
Kohgo, Yuji
中科院分区：
文献类型：
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作者：
Chueasamat, Anusron;Hori, Toshikazu;Kohgo, Yuji
为了减轻泥沙灾害造成的损失，了解降雨如何导致边坡失稳是必不可少的。本文的主要目的是通过试验研究地表砂层密度和降雨强度对滑坡破坏的影响。我们进行了一系列的实验测试，使用1g的物理斜坡模型构造霞浦砂和粉土命名DL粘土的渗透性残留表层和坚实的岩石基础，分别。共测试了9个案例，具有不同的表面砂层密度和降雨强度的组合。两种类型的故障：根据降雨强度和表层砂层密度，观察到表层滑动破坏和后退破坏。考虑了以下失效机制。起初，一些沙子，其中包含了大量的积累雨水，流出（流滑）在坡脚。流动滑移可能是由于有效应力的减少而导致的。当发生地表滑动破坏时，绝大多数砂层的孔隙水压力仍为负值，但整个砂层几乎处于饱和状态。在倒退破坏的情况下，渗流面上升到更高的位置，多余的PWPs出现在渗流面下。这种PWP值产生机制的差异可能是导致失效类型差异的决定性因素。(C)2018年由Elsevier B.V.代表The Japanese Geotechnical Socifty制作和主办。
In order to mitigate the damage due to sediment disasters, knowledge about how slopes fail due to rainfall is indispensable. The main objectives of this paper were to investigate experimentally the effects of surface sand layer density and rainfall intensity on the slop failures due to rainfalls. We conducted a series of experimental tests using 1g physical slope models constructed of Kasumigaura sand and a silt soil named DL clay for the permeable residual surface layer and the firm rock foundation, respectively. A total of nine cases with different combinations of surface sand layer densities and rainfall intensities was tested. Two types of failure: surface slide failure and retrogressive failure, were observed depending on the rainfall intensity and the surface sand layer density. The following mechanism of failure was accounted. At first some sands, which contained a lot of accumulated rainwater, flowed out (flowslide) at the slope toes. The flow slides may be due to the reductions of effective stresses as a result. When a surface slide failure occurred, most of the PWP (pore water pressure) values were still negative but the whole sand layers were almost at the saturation condition. In the case of retrogressive failures, seepage surfaces rose up to higher positions and excess PWPs appeared under the seepage surfaces. This difference of generation mechanism of PWP values may be the deciding factor in the difference in the type of failure. (C) 2018 Production and hosting by Elsevier B.V. on behalf of The Japanese Geotechnical Socifty.