Analysis,control And Forecast Of Deformation And Pressure In Soft Rock Tunnel

More than 70 per cent of energy is coal which occupies a pivotal position in construction of national economy in our country .With the development of coal mining s depth ,the problem of supporting and maintaining for soft rock tunnel becomes more and more conspicuous .Whether we can solve it properly is a keypoint for coal mining s development in depth and safety in production .So the thorough studying and exploring is urgent.This paper makes a systematic exposition for the characteristics and mechanics property of soft rock , characteristics of broken soft rock tunnel ,influence factors of surrounding rock s deformation ,supporting principle of soft rock tunnel and maintenance methods of tunnel etc .Proceeding from the bearing mechanism of soft rock tunnel ,this paper analyses the principle of interactin between soft rock tunnel s supporting and surrounding rock and it points out the principle of the best strengh matching between surrounding rock and bolting .It also the analyticly analyses for pressure of surrounding rock s and trestle load of soft rock tunnel . which put the theoretical foundation for deformation control analysis and numerical calculation of soft rock tunnel s surrounding rock and supporting.This paper applies emphatically the theory of the mine pressure and method of non-linear finite element ,and explores creatively the inverse operation method of supporting deformation and the pressure calculation in soft rock tunnel .It discusses new methods including in out boundary element method and forecast of temporary supporting pressure during the initial stage of excavation .These methods avoid the complexity of the problems which discuss directly .But it bases on actual measuring displacement (or stress ) of adjoining rock of soft rock tunnel and useing the optimization method of Hooke-Jeeves in order that the calculated displacement (or stress )can approach the actual measuring displacement, we calculate inversely the distribution of adjoining rock pressure acting on supporting of tunnel .The combine boundary penalty element with finite element has come true which can forecast directly the distribution of adjoining pressure during the initial stage of excavation and conclude the finite element for rmula of boundary penalty element .The methods are not only creative in thought and in theory and but also advanced in calculation means , which has great value both in theoretical and practicalSome international famous large finite element analysis programmes as SAP ANSYS and ABQUS are applied to the deformation and pressure calculation of soft rock tunnel s surrounding rock and supporting in the paper .Making the dynamic simulation display of surrounding rock s deformation true ,which improves the visionability of the variation of tunnel surrounding rock s displacement .We make a systematic analysis for the breaking forms and ideal fracture surface of soft rock tunnel ,conduct a deep research ,analysis and calculation for pressure relief maintenance methods of soft nock .By the practice of maintaining the pressure relief tunnel ,we confirms the pressure relief theory which tells us the pressure peak of surrounding rock will be deeper after pressure relief. In addition , combination supporting methods of well hole s soft rock tunnel are done by analogue simulation computation ,supporting practice and observation analysis.Time series analysis method gray system theory and artificial neural network are introduced into the research of the deformation and forecasting of soft rock tunnel in the paper ,which develop and work out the software as ARMH model and GM model .The three forecast methods are analyzed and compared in the paper.By the studying and practising of the paper , engineering analogy method is promoted to quantitative analysis .The paper searches a new way to calculate the pressure and deformation of soft rock tunnels surrounding rock and supporting .It will play important role in soft rock tunnel supporting.