本研究以砂箱配合地下水生產器,與人工模擬降雨實驗儀模擬不同地下水及降雨強度之作用,以觀測不同坡度、降雨強度及地下水壓時,土體位移之啟動、加速及結束等階段行為,以及崩塌破壞模式、土體飽和度、孔隙水壓值及土體位移之關係。研究結果顯示,地下水壓主控土體位移啟動,其水壓值會出現顯著之關係的變化,此種破壞的規模較大且多為漸進式;若是降雨入滲主控坡面位移啟動,則其土體含水量會有較明顯的變化,破壞規模較小且多為一次性大位移。降雨強度小時,位移較小且較緩慢。 當地下水與降雨同時進行時,濕潤線常在中層與入滲水分交會,使得土體中層之水分及水壓快速上升,進而也使土體位移加速。濕潤線與地下水交會後對於水壓值影響,僅對中層水壓值有較直接的影響;當降雨強度大時,濕潤線與地下水交會後進而使位移速度明顯增加,若降雨強度小時,雖會對位移速度產生影響,但卻較不明顯。中層之水壓值常可成為位移啟動的一指標。
The rainfall and pore pressure influence to failure behavior of the artificial soil slope is explored in the thesis.The sand box test includesgroundwater supply unit, artificial rainfall instrument,and monitoring system to figure out the relationship between the water infiltration and translation and the movement of soil slope.The water effect in the initiate, the acceleration, and the failure stages movement of soil slope are explored by several test setting. The sand box test shows that the case of pore pressure dominated slope sliding while the displacement acceleration increased with the pore pressure increasing. The failure mode exhibited the progressive failure.The case of rainfall infiltration dominated slope sliding while the displacement acceleration increased with the water content increasing. The failure mode exhibited a small andfast failure. When groundwater and rainfall are applied to the sandbox test simultaneously, wetting fronts of rainfall infiltration and pore pressure crossed in the middle layer of sandbox, then yielded the increasing rate of water content and pore pressure rising up while the displacement is also accelerating.The displacement speeds up signicificantly in heavy rainfall while wetting fronts crossed. Oppositely, the displacement accelerationis not signicificantin light rainfall while wetting fronts crossed. The pore pressure of middle layer can be an good indicatorto the soil movment.