| This paper focus on the evolution of cracks in the broken and plastic zone of roadway surrounding rock, the breakage effect of weak structure, and the control mechanism of non-equal support.The producing and development of crack are not the immediate reason to destabilize the roadway. In the production scene, the macro-crack develops in almost all the surrounding rock in the roadways which are in their good state, and most of them penetrate through the strata. After incised by the penetrating cracks, the intact strata can form new mechanics equilibrium structure. Although the load-carry ability of new structure is weakened markedly, the structure equilibrium is maintained all the same in the low stress condition with absence of high stress, and the surrounding rock still maintains his stability. When the stresses in the surrounding rock are distributed again, the mechanics equilibrium may be broken, and the destabilization breakage of new structure finally conduces to the destabilization breakage of surrounding rock.The study indicates that there is a obvious behavior characteristics to localize in the deformation breakage of roadway surrounding rock. Under the influence of high ground stresses, the localization of surrounding rock deformation result in the crack produce and development. The development of crack is in the way of wing shape. Plank-like structure is produced in surrounding rock when the crack develops to a extent. There are close relations between the plank-like structure far stress field distribution, and the extending direction parallels with maximum primary stress.The study still indicates that buckling or shearing will develop of plank-like structure is compressed more, excessive buckling or shearing will lead to destabilization and eventually the destabilization of the surrounding rock.The bolted support may control to a certain extent to buckling or shearing of the plank-like structure.To control the buckling of the plank-like structure must consider the anchor rods two aspects. The one is the anchor rod density, it may be calculated by calculating the number of anchor rods which be needed to control the plank-like structure with certain length. The other is the rigidity of the anchor rod, it may be determined by calculating the rigidity of n elastic supports which be needed to control the plank-like structure with certain length.The anchor rod number which be need to control the plank-kind structure stabilizes with the length of the plank-like structure becomes the linear growth relations, and with the uncut stresses becomes the even parabola growth relations, but with the rock mass elasticity coefficient becomes negative exponent power function relations reduction which exponent is (-1/2), and with the thickness of the plank-like structure becomes negative exponent power function relations reduction which exponent is (-3/2). Therefore, to control the development of crack in surrounding rock in the way is one positive supports way.The rigidity of the anchor rod which be need to control the plank-kind structure stabilizes with the uncut stresses becomes half cubic parabola relations growth relations, but with the rock mass elasticity coefficient becomes negative exponent power function relations reduction which exponent is (-1/2), and with the thickness of the plank-like structure becomes negative exponent power function relations reduction which exponent is (-3/2), too. Anchor rod rigidity regarding plank-like structure stable extremely important, the enlarge anchor rod installs when the pre-stressed may increase the anchor rod the rigidity.Furthermore, the engineering geology of upside roadway of 1304 working face is evaluated, and the theory of micro-crack's evolution and surrounding rock's softening, and the theory of evolution and stability of macro-crack in surrounding rock are studied in this paper. The mechanism and countermeasure of non-equal support by bolting-meshing-cable in upside roadway of 1304 working face are researched additionally.
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