The Yanchang County Geology Disaster Distributes The Rule And The Stability Analyses

Recently, with the rapid economic development and increased human activities, geological hazards have occurred frequently in China. Direct economic losses caused by geological hazards were up to 27 billion yuan each year. Geological hazards have become the important factor of constraint on economic and social development, deterioration of the ecological environment. So detailed investigation become increasingly important.to the stability analysis of the geological hazards.The thesis combined with'detailed investigation of geological hazards in Yan'an of Shaanxi Province', which issued by Geological Survey Bureau of China in 2007. Base on the detailed investigation and laboratory work, the type of geological hazards in Yan Chang county were measured. The development characteristics and distribution of geological hazards were summed up. The forming conditions and affecting factors of geological hazards were analyzed. The stability and forming mechanism of the main geological hazard points were evaluated and analyzed.Through the collation of information on the survey Statistics know: the geological hazards in Yan Chang county are divided into four types: unstable slopes,landslides,collapses,mudslides hidden dangers. Base on the status analysis, geological hazards mainly developed in the northwest and distributed uneven in Yan Chang county. There are very little development of geological hazards in the southeast of Yan Chang county. Hazard points are almost medium and small size. The major geological hazard types caused harm to human are collapses and unstable slopes. The hazard points are mainly caused by human. It was verified initially that geological hazard regions are affected by terrain and landform in distributed rule, are developed mainly in the western loess run-off ditch and the area between loess ditch in space, they were distributed in laminate way, some were distributed in strip way along the valley terrace; also they were developed in the precipitation centralized year and every June to September in time.Through the in-depth research and analysis on forming conditions and affecting factors of geological hazards in Yan Chang county, the controlling factors are topography. The material basis are stratum and lithology. The triggered factors are atmospheric precipitation. The affecting factors are human activity.Finally, unstable slopes, landslides and collapses are simulated and stably evaluated by Flac / Slope and Chek projection software.