Study On The Control Mechanism Of Continuous"Double Shell" Surrounding Rock In Deep High Stress Soft Rock Roadway

With the exhaustion of coal resources day by day,Coal resources in deep mining has become an objective necessity of deep coal mining has become one of the focuses of research in the field of mining at home and abroad.Along with the increase of mining depth and strength, the surrounding rock of deep roadway shows different mechanical response mechanism compare to the shallow surrounding rock.Surrounding rock in "three high and one disturbance" complex mechanical environment, rock deformation characteristics has undergone a fundamental change, the roadway surrounding rock of the engineering characteristics of soft rock, has the obvious creep and rheological characteristics, the dilatancy phenomenon is serious.At the same time, disaster possibility increases sharply under high stress in deep roadway dynamic, which bring greater threat to safe and efficient mining in deep mine.The key problem of the deep exploitation of coal resources is to solve the deep roadway supporting, a large number of engineering practice and theoretical research have shown that the traditional shallow roadway support theory and technology has been unable to adapt to the deep roadway support requirements.In this paper, based on the continuous "double shell" support theory, the deformation and failure law of soft rock roadway in deep high stress engineering is analyzed, and the physical model of continuous double shell support is constructed,Specific conclusions are as follows:(1)although part of deep roadway surrounding rock’s own strength is relatively high, but exhibits the properties of soft rock under high stress, traditional shallow roadway supporting theory and branch support has been unable to meet the deep engineering of soft rock roadway supporting demand, In urgent need of research work for deep high stress soft rock roadway support problem, the support of deep high stress soft rock roadway is realized.(2) the factors that affect the soft rock of deep high stress engineering are analyzed, and the main factors that affect the soft rock roadway are complex stress,surrounding rock properties, groundwater action and support design.(3)Through numerical simulation analysis of the deep high stress roadway in not supporting case, regardless of roadway in high level should force or high vertical stress,surrounding rock of roadway showed large deformation, strong rheological, selfstabilization required a long time characteristics. In addition, the high level of stress,roadway roof and floor relative movement amount was significantly greater than that of two sides roadway convergence, especially heave amount is very large, indicating that in deep high stress force engineering of soft rock roadway supporting should be strengthened, of floor roadway support, better assurance of deep roadway stability.(4)Theoretical analysis of the bolt(anchor) axial and lateral support, the roadway surrounding rock grouting reinforcement mechanism. According to the different rock roadway in the mechanical state, distributed by the C-M yield criterion and Drucker Prager Yield Criterion, draw the continuous double shell branch support, roadway surrounding rock rupture zone, plastic zone and elastic zone stress variation, rupture zone, plastic zone radius, rupture zone and plastic zone of surrounding rock displacement and construct the continuous "double shell" support model.(5) Design of the continuous "double shell" supporting similar material experiment. By comparing the roadway floor the continuous "double shell" support and general support, continuous double shell support can better control of roadway surrounding rock stability have been obtained. It can not only reduce the roadway floor heave, can also and roadway roof and two help supportings to synergetic support protective effect, reduce the roadway roof and two for the displacement.(6)Design the different buried deep under the continuous "double shell" a door shell parameters of similar material experiment and numerical simulation, obtained under the different shades of shell total thickness the same shallow Department shell thickness, different shallow shell thickness of the same depth of shell total thickness of roadway surrounding rock deformation rules and obtained in the continuous "double shell" support should be first to determine the continuous "double shell" a total support thickness, and then select a reasonable shallow shell thickness, thus to better enhance the continuous "double shell" supporting the rationality of.