Cut The Layered Rock Landslide Stability Evaluation And Governance Programs

Because of the unique landform, lithology, geological structure, and the especially the difference new tectonic movement, the landslide is abundant in the Qinghai-Tibet Plateau. According to the statistics from 1990-2005, 671 landslides developed in Qinghai province, among these, 246 are hard rock landslides, accounting for 36 percent of the total. With the continuous development of the society and economy, as a kind of geological disaster, the occurrence of landslide has great influence to human life and property, city construction, development of economy, and the protection of historical relics.Takinging the V and VI landslides in the Longwu town of Qinghai province as an example, using the methods of geological survey, surface exploration, drill hole sampling, groundwater analysis, laboratory and field experiments, it is thought V and VI landslides inherit the characteristics of old landslide, and have the shapes of irregular ribbon. The body of the slides are mainly gravel and mild clay, mud gravel scree, sand-clay rock and clay soil. From surface down, the structure changes from loose condition to tightness. The beds of the slides are mainly composed of stiff and compact mud rock. The characteristics of the deformation of landslides are mainly ground cracks, in some places collapse may also occur. The cracks and the collapse distribute in the foreside and middle part of the landslide. It's size and morphological characteristics are different. The creepage deformation of the landslides is connected closely with the landform condition. The disadvantageous geological structure and the topographical condition are the main internal causes which the new landslide occurs. Water and human activity is the stimulative factor for the occurrence of the landslide. Through stability calculation and engineering geological analysis, V and VI new landslide is in steady under the circumstances of no continuous rainfall or heavy storm, and earthquakes. The corresponding stable coefficients are 1.14 and 1.07, respectively. The stable coefficients become 1.02 and 1.01 respectively, under the circumstances of earthquake but no continuous rainfall or heavy storm, which means the landslide is in a critical condition. In the circumstances of continuous rainfall or heavy storm but no earthquake, the stable coefficients become 0.996 and 0.92 respectively, all are smaller than 1.0, indicating the landslides are in the instable state. It can be seen that water has more impact to the landslide than earthquake or other load. Under the circumstances of continuous rainfall or heavy storm, and earthquakes, the stable coefficients become 0.89 and 0.87 respectively, which is much lower than 1.0, indicating the two landslides will slide without doubt. Based on the above results, the prevention and cure measures are optimized. It is thought the drainage of water, supporting, lowering the earth, and sealing the cracks are the comprehensive optimized plan. This plan takes the internal and external driving forces as the factor, which not only prevents the infiltration of surface water, enhances the ground intensity, increases the stability of whole landslide body. The construction materials can also be obtained nearby. The condition of construction site is good, the investment is reasonable, the time of prevention and cure is short. This program gives an important guidance the prevention and treatment of the similar landslide in Qinghai .