Motion Feature Of Rock Falls And Collapse In Mountain Of Li Jia Wu Ji And Its Prevention Measures

Rockfall of Li jia wu ji lay in Yijia gully Xinhua village Guangzhuang town Qingchuan county Sichuan province. It consisted of seven unstable rocks. Unstable rock area located in the top mountain of Li jia wu ji two sides and to the top of ridge steep. By the earthquake of wenchuan sichuan province on May 12th, the influence of disasters, crack stronger body deformation status is not stable. Based on the comprehensive and systematic understanding area studied topography and geomorphology, stratigraphic lithology, geological structure, weathering unloading, groundwater and ground stress state, on the basis of geological conditions. Comprehensive paper including the unstable rock formation and its development process, mode and classification of deformed unstable rock, the stability calculation dangerous rock, every stage of the collapse rockfalls movement characteristics, falling collapse Engineering prevention measures.The main study content and conclusion of this paper are as follows:(1) Collapse is a very common phenomenon of geological disasters, before formation the collapse occurred first have the prerequisite is dangerous rock with sufficient development. The development of unstable rock formation is a continuous accumulation and the factors affected the process. Unstable rock factors are topography and geomorphology, geological structures (new tectonic movement, earthquake), stratigraphic lithology, topography, rock mass structure types, hydrology geology condition, etc. This paper will research the influence factors boils down to erosion, gravity, and seismic action, rainstorm, and human activities.(2)According to the scene a lot of exploration measurement information, we study on unstable rock deformation instability mode and classification. We according to the dangerous rock lithology combinations and the collapse of the existing study areadamage phenomenon dangerous rock include slumping type,topple type and fall type three kinds, we determined the main influence factors and clear between affect in factors and character of the relationship based on the stability calculation model established respectively, and stability calculation analysis. (3)We analysis the influence the stability of unstable rock fracture water pressure used soft of UDEC. We mainly produce crevice water to rock portion extrusion destruction, make rock mass structure cracks and produce pull on the vertical surface expands; under the action of the torrential rain Rock fracture method to increase structural surface pressure to expand. Final it cause of hazards of Collapse and falling stones.(4)We clarify the Features and calculating methods of Collapse and falling stones movement various stages by Dynamics, kinematics and energy transformation theory. Our path to collapse rockfalls qualitative calculate and compares the rockfalls already happened. We proved the basic accuracy and can simulate better guide engineering practice.(5) Details of our discussion and analysis and comparison the existing protection system, Based on characteristics of the collapse of the roof falling movement, comprehensive analysis,we consider high and steep and unstable rock slope height and the initiative on slope protection measures difficult to implement. Advice to the researched area uses Stone Falling Wall or protecting net.