Study And Analyze On Advanced Small Pipe's Support Parameters And Stability In The Tunnel

Due to poor condition of surrounding rock and low since the steady ability is easy to cause the tunnel collapse accidents occurred in the process of excavation,causing significant damage to the human,material and financial resources.Therefore,in order to guarantee the tunnel construction to the implementation of the safety,economy,the need when tunnel excavation the preliminary support of the necessary measures.The advance guard measures also many,advanced small pipe is common,as one of the measures to advance guard a preliminary support method,this method can obviously improve the lithology and stress of surrounding rock,the tunnel smooth construction in some adverse geological conditions.Practice shows that the advanced small pipe in practical engineering is good for develop its economy,flexibility and reinforcement effect.Therefore,research on the preliminary support of the tunnel advance ductule becomes very important.Based on the tunnel advance ductule as the research object,through a lot of research and consult a large number of related literature at home and abroad,specific to advance ductule effect of supporting parameters and stability analysis.In this paper,the complete content include:?Through the calculation of tunnel surrounding rock stress of several common theory,comparative analysis of their respective advantages and disadvantages and the use of the surrounding rock,and it sums up the advanced small pipe in the surrounding rock stress load conditions.?Winkler elastic foundation beam theory with simple comparison Pasternak elastic foundation beam theory,combined with the actual status of mini tube in advance,the choice after as the basis of advanced small pipe mechanics model is set up,thus further to advance ductule mechanical behavior analysis.?Using the finite element software Midas/GTS to advanced small pipe length,Angle of extrapolation,ring to the spacing and diameter of supporting parameters for numerical simulation analysis.?Constructed on the basis of the actual project,the preliminary support of the advanced small pipe structure model,simulation analysis on its reinforcement effect.