Research On Disaster Risk Assessment In Derong County,Sichuan Province

The ecology is vulnerable and structure is complex in the southeast of China.Mudslides, collapse, landslides and other geological disasters are widely distributed,suddenly strong and destructive. The frequent occurrence of geological disasters,caused significant damage to people’s lives and property.Derong, the study area, alarge number of geological disasters in the region for analysis, the study of thegeological hazard assessment.The place of human activity in the study area located in the high frequency ofgeological disasters in the region, this incident triggered a chain reaction of geologicaldisasters chain and the ecological chain.First, on the basis of the work of Deronggeological disaster prevention planning, Collect a lot of basic information on thestudy area, Including Geological disasters in the history of information, as well as thestatus quo.Through field investigation and mathematical analysis,We get the law ofthe development of geological disasters, distribution characteristics and formationmechanism.Elements, including the impact of geological disaster control conditions,and induced conditions, was selected as the evaluation index.Quantitative evaluationof the risk of geological disasters, the use of the evaluation unit of the grid, theamount of information law, the analytic hierarchy process, geographic informationsystems, divided into high, medium and low risk zone of the geological hazard FigureThe main contents are as follows:(1) the law of the development of geological disasters, distribution characteristicsand formation mechanism are discussed.Geological disasters, the development of the factors interact and influence eachother.Through investigation and analysis to determine the topography, lithologystructure dominated by many factors, it determines the conditions of geological disasters, the driving force size and energy conversion, and the accumulation of loosedebris material generated the possibility of disaster. River, rainfall, and engineeringactivities and other factors play a role to promote and stimulate the formation anddevelopment of geological disasters.After repeated screening, and ultimatelydetermine the slope, slope height, slope, engineering rock group, the main fault,stream, engineering activities, the seven hazard.(2) To establish the information model, the analytic hierarchy process model forthe evaluation factor weighting.Information model based on the identification of geological hazards data,through the mutual information calculated by the amount of information provided bythe evaluation factors of geological disasters, complex problems is to quantifyoperational. The analytic hierarchy process to the thought process to be quantitativecalculation of the judgment of the importance of evaluation factors. By constructing ahierarchical structure of the geological hazard evaluation, construct the judgmentmatrix to get the desired result, and passed the consistency test.(3) Regular grid cell for the evaluation unit, the application of GIS weightedoverlay analysis on the factor.On the superposition of the results to set the threshold to the study area wasdivided into high, medium and low three danger zone.Two models, the conclusion isrelatively close to the evaluation results to Derong to disaster status quo is moreconsistent. Finally, analysis of geological disasters in the danger zone status quo, andto propose preventive measures.