The Technology Research Of Hazard Degree Assessment Of Landslide In Bailong River Basin

Landslide is an important form in geomorphic evolution, which is a significant and typically global natural geological disaster moving based on the block. If landslides occur, interruption of traffic, river blocked, towns buried and other phenomena will happen, and it will bring serious disasters to the living environment, property and agricultural activities of human being. Bailong River basin is a high incidence of geological disasters area, locating in the erosion region of high mountains in west of our country, earthquakes and torrential rain is conducive to the resurrection of new and old landslide, therefore the landslide hazard zonation of different scales is particularly important.On the base of a comprehensive landslide hazard zonation research, the following three aspects were studied:the system establish of different scales (regional and single) landslide hazard zonation; the method of different scales landslide hazard zonation includes evaluation of the basin scale (Bailong River basin), the town scale and typical single landslide hazard, in order to achieve the figure of hazard zonation; Stability analysis of Duanheba, Suoertou and Xieliupo in Bailong River basin.First, the Sensitivity Index Analysis Method is used to calculate the average sensitivity of each effect factors, the numerical value greater than1is selected as the index system of landslide hazard zonation in Bailong River basin, including of land use(1.992), geologic time(1.262), elevation(1.123), stream buffer(1.059), distance to fault structure line(1.058), earthquake(1.035) and gradient(1.014). Information measure and contribution weight approach are used to research the hazard zonation of Bailong River basin and the around of the town of Zhouqu, achieved the conclusions that the contribution weight approach is more suitable for the landslide hazard zonation, which has a small region and a accurate basic data, while the information measure structure has little associated to the area of the region evaluated; Secondly, the Altitude Difference Gd, gradient G, slope structure Od, slope type Sf, formation lithology St, distance to the river L, volume V and the content of block stone K were used as index system to the single landslide hazard zonation, using the Information Entropy, Analytic Hierarchy Process and synthesis index method of weight to proceed hazard assessment of the twenty one single landslides in the study area, comparison shows that, the agreement of Analytic Hierarchy Process and Information Entropy evaluation result is76%, the agreement of synthesis index method of weight and other two methods is86%and90%respectively, which is higher than the former, so synthesis index method of weight is selected to conform the final evaluation results; Finally, the stability of three single landslides Suoertou, Xieliupo and Duanheba are analyzed, and the conclusion is that, the three single landslides are instability under the natural condition, storm condition, earthquake condition and the condition of storm and earthquake, landslide is very easy to occur, which will have a harmful effect to the resident.Bailong River basin multi-scale landslide hazard zonation, the system establish and the hazard assessment research were completed in this paper, in order to obtain comprehensive landslide hazard zonation achievement, which has theoretical and engineering significance to the human security, environmental protection, construction safety and disaster prevention in Bailong River basin.