Study On Risk Assessment Of Suoertou Landslide In Zhouqu County,Gansu Province

Landslide Hazard is one of the most common and serious geological disaster, every yearit causes a loss up to billions of dollars in the whole world. This hazard gives great damagesto the national economy and people’s lives and properties. And they are the verysingle-landslides that lead to the loss directly. So, in the face of serious landslide hazards, inorder to measure the influence of hazard on lives and properties a risk assessment theory andmethods needs to be researched and applied to; At the same time, Suoertou landslide which isin Zhouqu county, Gansu province, is in a stable state now, but has the probability to faile inheavy rain and earthquake factors are still sliding will may, and the threat to the local people’slife and property security, so it is very necessary to make a risk assessment.Based on the risk assessment results of landslide hazard both at home and abroad, theauthor describe the method of the risk assessment of single-landslide hazard. The maincontent includes the method of single-landslide hazard analysis, the vulnerability analysis ofelement at risk and single-landslide hazard risk estimation, and the determination method ofprobability of single-landslide failure and loss rate of element at risk and estimation of totalrisk are put forward.Risk assessment is made for the Suoertou landslide, using the method studied above.Based on field survey and data collection, the essential feature analysis of Suoertou landslideis studied firstly. Then the hazard analysis of Suoertou landslide is studied. The analysisresults show that, in the factors of natural, storm, earthquake and storm+earthquake theoverall safety coefficients of Suoertou landslide are1.649,1.141,0.888and0.796, under theinfluence of factors the stable state of Suoertou landslide is unstable to basic stable, and usingmethod of dynamic analysis and condition analysis method of single-landslide the probabilityof single-landslide failure is calculated, and the results are0.018,0.056and0.003, andSuoertou landslide potential hazard range predicted by calculating the maximum slidingdistance of single-landslide hazard and blocking the river height; Then, make an analysis forvulnerability of element at risk within potential hazard range of Suoertou landslide, gettingthe hazard-affected probability and loss rate of element at risk, and calculating the value lossofelements at risk, emphasizing at studying the method of hazard-affected probability of element at risk, calculating the value loss of people’s life and property value; At last, throughthe value at risk, and the formula of lock that head son landslides at different factors of thepopulation value at risk are34.12,97.13and5.21, the property value at risk are163.4509million yuan,508.5135million yuan and27.2418million yuan respectively.This paper puts forward a risk assessment method which is applicable to single-landslide,taking Suoertou landslide for example. The technique and method adopted and the idea havesome value and use for reference to other single-landslide.