中文摘要：

滑坡是一种常见的地质灾害,灌溉诱发黄土滑坡失稳是常见地质灾害之一。灌溉作用不仅改变了地下水平衡,而且降低了土体的抗滑强度,从而导致黄土滑坡的发生。针对黑方台焦家崖头13号黄土滑坡,开展了灌溉作用下滑坡失稳机理的离心模型试验研究,揭示了黄土滑坡的变形特性、应力水平及破坏模式。离心模型的制作考虑了"粒径效应"、"尺寸效应"。离心试验结果表明:随着加载时间和离心加速度的增大,模型坡体沉降量、坡体土压力、坡体孔隙水压力均逐渐增大;坡体沉降量由坡顶至坡脚逐渐减小,最大垂直位移为33.38 mm,坡体土压力由坡顶至坡脚逐渐增大,最大土压力为320 k Pa,坡体孔隙水压力表现为坡顶>坡脚>坡体中部,最大孔隙水压力为157.08 k Pa;坡体呈现出两级破坏模式,即第一阶段的坡脚蠕动变形,坡顶压制拉裂,第二阶段的坡体剪切滑移。

英文摘要：

The landslide is a common geological disaster, and the loess landslide instability induced by irrigation is one of the common geological disasters. Irrigation function changes the balance of ground water and reduces the resistance strength of soil mass, resulting in the occurrence of loess landslides. For the loess landslide No.13 of Jiaojiayatou, centrifugal model tests on landslide instability mechanism under irrigation effect are carried out. The deformation characteristics, stress levels and failure modes are revealed. The preporation of centrifugal model considers the influences caused by "particle size effect" and "size effect". The results show: (1) With the increase of loading time and centrifugal acceleration, the settlement, earth pressure, pore water pressure of model slope all gradually increase. (2) The slope settlement gradually decreases from the slope top to the toe. The maximum vertical displacement is 33.38 mm. The soil pressure of slope gradually increases from the slope top to the toe. The largest earth pressure is 320 kPa, the pore water pressure is the largest at the slope top, that at the toe is followed, and that in the middle is the smallest, and the maximum pore water pressure is 157.08 kPa. (3) The slope emerges two failure modes:one is creep deformation of the toe and pressure-induced crack of the top, the other is shear slip of the slope.