Research On Collapse And Reinforcement Principle Of Dangerous Rock Of Hongyadong In Chongqing

With the constructing of Sanxia Engineering and exploiting of Western China, the geological hazard in mountainous areas is increasingly serious. The study of collapse of dangerous rock is a focus among researches of various geological hazards. Based on current domestic and foreign researches on dangerous rock and applying the Hongyadong dangerous rock project in Chongqing as the example, the following contents are researched:At beginning, the details of engineering geology on the area are introduced, including the conditions of engineering geology and hydrogeology. According to the data of the report of reconnaissance and applying all kinds of experiential methods, the mechanics parameter is provided for further analysis. After researching the loads on dangerous rock synthetically, the author points out the development and collapse mechanism of dangerous rock: The geology foundations that forms dangerous rock are the constructional surfaces such as tectonic fracture,relief fissure, soft interlayer etc.. The developing of dangerous rock is due to release of in-situ stress in rock,aeolation,water erosion and root flerry. The main loads leading to collapse of dangerous rock are gravity, water pressure and earthquake force.The main reason that the current design ability of control dangerous rock is poor is that the loads on dangerous rock don't be understood fully. Aiming to this situation, the in-situ stress in rock and the water pressure are researched. The in-situ stress in the slope is measured through relieving stress by overcoring. Then the analysis that in-situ stress in slop influences the development and stability of dangerous rock is carried on by fracture mechanics.Water pressure includes hydrostatic pressure and hydrodynamic pressure. At present the hydrostatic pressure is overvalued. To solve this problem, the model of steady state water line in rock crack during the rain is built in cha5. The author applies correlative SeePage theories on this model to found the calculate method. Then the practicality formula of hydrostatic pressure in dangerous rock is supplied. In this thesis, dangerous rock was classified into three styles: cantilever dangerous rock, wall- pillar dangerous rock and pyramid dangerous rock. The ANSYS software is used to analyze the collapse pattern of each style. Based on this conclusion, the calculate method used in engineering is provided at last. The results of this dissertation can be consulted for the geotechnical engineering designers.