Study On Large Proportion Similar Simulation Experiment Research Of Roadway Bolting Support

By laboratory experiment and similar simulation experiment, this paper uses bolting support similar simulation experiment platform developed by China Coal Research Institute (CCRI) to conduct similar simulation experiment for two different types roof model,experiment monitoring systems are introduced in this paper. The research results are as follows:(1) The experiment platform can conduct simulation experiment with geometric similarity ratio of 1:2 for the roof with the dimension of 2600mm×2000mm×1000mm.The hydraulic loading system of the experiment platform can realize true triaxial loading,and the maximum loading capacity of vertical is 15000kN.(2) A set of large proportion of roadway bolting support similar simulation experimental simulated bolting support materials is developed. (3) Developed a large proportion of similar simulation experiment of roadway monitoring system,which includes bolt force, steel belt force, roof subsidence and separation, strain change of model internal,dynamic monitoring of model’s internal fractures, bottom crack changes, etc. (4) Similar simulation experiments is conducted for two different types of roof model and the conclusions are as follows:①When lots of fractures and bedding planes are formed, the roof’s finally resistance to deformation reduces greatly. Extending of vertical fracture is greatly reduced for a wide range of delamination, fractures spreading and extending affect. ②The damage of model 2 is influenced by many factors,overall destruction with different form and large scale can be found, the key of roof support is control the fracture extension and rock abscission layer.While model 1 shows single and small range partial destruction,the key of roof support is control the theory weak surface generation, expansion and extension.③The sound emission can accurately predict initial fracture’s position, expanding paths and extending height in the bottom of model 1.Which alsocan reflect the damage time and degree timely and objectively.④ When roof is integrated, bolt take effect only for the partial destruction part, the function of bolt is control the theory weak plane generation and extension; while the incomplete roof damage at the basis of initial fracture and bedding plane, bolt reinforce the roof as a whole to bear, avoid further damage of the roof, the individual and overall of bolt take effect to the roof.⑤Steel belt has no significance effect for the overall subsidence roof, while for the uneven roof subsidence and deformation, steel belt can quickly increase the supporting resistance and control the fracture’s further extension and deformation.;⑥When roof damage and deformation as inconsistent way,the bolt and steel with the roof as a whole to bear and deformation, timely increase supporting resistance,inhibiting roof uncoordinated defromation and damange further expansion.