Influence Of Rising And Falling Of A River Water Level On Groundwater Flow In A Lanslide And Stability Of A Lanslide

In southwest China, a large number of landslides threat people’s lives and propertywhich distribut along the river. Different from general mountain landslide, this type oflandslide stability is mainly affected by the water level fluctuations on the occurrence ofgeological environment change, especially during flood period effect is the strongest.The change of the river belongs to the unstable flow problem which affected by therise and fall of the water velocity and permeability coefficient of the landslide, accuratemethod to consider these factors to determine the saturation line, then based on thesaturation line to determine the osmotic pressure and stability analysis. How toaccurately determine the saturation line and how to select the calculation method andworking conditions is the main problems of this type of landslide. In this article havefollowing views:(1) Comprehensive analysis the landslide’s Landform stratum lithology geologicalstructure and geological characteristics of the water level, think that the landslide is in adevelopment bedrock small artificial accumulation on the surface of the soil landslide.The landslide under natural condition in a stable state, but under the Changing of theriver, front of the body be damaged first, pulling the back of the slide body moveforward, so that the whole landslide deformation and failure.(2) Through seepage simulation the landslide area of groundwater. When the watersurge, with slope before the rise of water level, groundwater in the slope body isgradually increased, Influenced by coefficient of permeability of rock mass, landslideby the slope surface for the slope is deep inside, the saturation line shows the high tolow trend. (3) When the water drop, slope landslide groundwater landing speed is far laggingbehind the river landing speed, near the slope in the front of the saturation line is curved,the river landing speed decreases, and degree of saturation line bending also decreasedaccordingly.(4) River surge process of landslide stability first rise and then decline and thenrise, when the river rose to a certain height，The faster the river rise, stability oflandslide is slightly lower, shot up in the process of the minimum stability coefficientcompared with the natural condition, falling by3%.(5) The water plunged cause the decrease of landslide stability. When the waterlevel get to the bottom of slop, it is stability to achieve the minimum. In the river whenit plunged to a certain height, the faster the river landing, the lower the landslidestability. The water plunged influence on the stability of the landslide, slump in theprocess of minimum stability coefficient can reduce about30%compared with naturalconditions.