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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。
Landslide is a common geological disasters. Irrigation induced instability of loess landslides is one of the common geological disasters. Irrigation has not only changed the groundwater balance, but also reduced the soil anti-skid strength, resulting in the occurrence of loess landslides. Aiming at the loess landslide at Jiajia 13, Heifangtai, the centrifugal model test of instability mechanism of landslide under irrigation is carried out, and the deformation characteristics, stress level and failure mode of loess landslide are revealed. Centrifugal model of the production of “size effect ”, “size effect ”. The results of centrifugal test show that with the increase of loading time and centrifugal acceleration, the settlement of model slope, the pressure of slope soil and the pore water pressure of slope gradually increase, and the settlement of slope decreases gradually from the top of slope to the foot of slope , The maximum vertical displacement is 33.38 mm. The soil pressure on the slope gradually increases from the top of the slope to the top of the slope, and the maximum earth pressure is 320 kPa. The pore water pressure of the slope manifests as the top of the slope> the foot of the slope> the middle of the slope, The pressure is 157.08 kPa. The slope shows two-stage failure mode, that is, the first stage of the foot peristaltic deformation, the top of the hill to suppress the crack, the second stage of the slope shearing slip.