Research On The Development Regularity And Triggering Mechanism Of Geological Hazards In LongChi

Geological hazards in LongChi mainly trigged by"5.12"Wenchuan earthquack, The Longmen mountain fault zone cross the research area. the Geological Hazards developed extensive, muck destructive and widespread ,made for much misery in research zone .The paper focuses on the earthquake induced geological disaster in Longchi,. According to a large number of geological field investigation and collecting and analyzing the information of earthquake.The paper expatiated on the characteristics of the geologic hazard in research zone, summarized the regular pattern of the landslide and rock fall, that the geologic hazard distribute on both sides of the fault zone, decreased progressively the further awayBase on the geological field investigation, the paper analyzed the characteristics, mechanism,movement and controlling element of landslide and ,rock fall, dangerous rocks systematically.After analyzing the outcome,further Focus on what the Internal Factors such as geologic structure, Topography,and rock mass structure and external factor suck as seismic acceleration,height multiplication affect the stability,how the horizontal acceleration and Vertical Acceleration interact .Then calculate the seismic acceleration by momentum transfer and Back-calculating method.All kinds of slope and Isolated Stone are analysed and discussed from different height of slope, types of slope, Topography, slope structure.At the end ,the paper point out the multinomial factors should be considered in the stability analysis.The result of the study showed that four conclusion:(1)The earthquake is the main .trigger of the Geo-hazards that range 500 meters of the fault less than, occurred at elevations of 1 000-1200 m above sea level.The landslide occurred at elevations of degree of slope 30°~35°,slide about 50°~60°.(2)Seismic wave and acceleration will be magnified by Topography in research zone,especially at the thin ridge of a hill isolated and independent mountain top. This paper researches on acceleration magnification effects, according to all the calculation results of the seismic acceleration are larger than 1g, the seismic acceleration in a few geologic hazards is larger than 2g.(3)Under earthquake actions, the seismic response of All kinds of slope and isolated stone are analysed and discussed from different height of slope, types of slope, topography, slope structure.The seismic response is the more obvious the higer elevation,the more fragmentized , the concaves and convex slope shape is most likely destabilization.(4)According the calculation ,the Geo-hazards point is stability in nature condition ,unstability when earthquake happened . a tiny minority Geo-hazards points in research zone is unstability.