Study On Stress And Deformation Characteristics Of Surrounding Rock In Rectangular Roadway

In practical engineering,the rectangular tunnels is the coal mine roadway,a common due to its relatively simple for construction,fast into the lane,is advantageous to the coal mining working face end support,and the advantages of rapid advance of mining work face,widely used in the coal mine in our country.At present,the stability analysis of surrounding rock in circular roadway has formed a relatively mature theoretical analysis method,but less research on rectangular roadway.Therefore,it is of great theoretical and practical significance to study the stability of surrounding rock of rectangular roadway.Based on theoretical analysis and numerical simulation,this paper studies the stress distribution law of surrounding rock of rectangular roadway and the width of plastic zone,and obtains the following main results:?1?Based on the complex function theory,uses the method of conformal mapping and the rectangular roadway surrounding rock to complex plane mapping function on the unit circle,rectangle stress of surrounding rock of roadway is deduced expressions,further analyzes the aspect ratio,lateral pressure coefficient,tunnel buried depth change when rectangular tunnel surrounding rock stress distribution law;?2?The stress distribution,roadway roof and two displacement deformation of rectangular roadway are simulated by FLAC^3D software.This paper analyzes the influence of lateral pressure coefficient and width height ratio on the deformation a nd failure of surrounding rock of rectangular roadway.?3?Based on ultimate equilibrium theory,combined with equilibrium principle,Zienkiewicz-Pande criterion was utilized in this thesis to deduce the analytical solution of the width of surrounding rock plastic zones in rectangular tunnels.Through living examples,calculation was conducted and single factor analysis was adopted to analyze four major factors influencing the changes of width of plastic zones.Therefore,the changing rules were also obtained.Besides,a comparison between Zienkiewicz-Pande criterion solution and Mohr-Coulomb criterion solution as well as Drucker-Prager criterion solution was carried out.to verify the correctness of the analytical solution,it is concluded that the selection of yield criterion of rectangular tunnels of plastic zone width calculation result has a certain influence,plastic zone width calculation in rectangular tunnels should select proper yield criterion.Numerical simulation software is used to further analyze the distribution pattern of the plastic zone of surrounding rock of rectangular roadway when the width and height ratio and lateral pressure coefficient are changed.