Optimization And Practice Of Surrounding Rock Support Parameters For Auxiliary Haulage Roadway In Dual-roadway Layout

In the underground coal mining of our country,double-roadway layout style is common in longwall working faces,which is widely used in recent decades.However,in practice,the auxiliary in the double-roadway arrangement generally bears the dualinfluence of mining in the upper section and the working face of this section,resulting in large deformation of surrounding rock in the whole cycle of the roadway,and the evolution law and deformation and failure characteristics of surroundings rock mining stress are different form those of ordinary roadway.The working face of Cuncaota No.2mine adopts the double-roadway arrangement,and the surrounding rock deformation is small and the stability is good when the auxiliary transport roadway serves the upper working face during mining.However due to the influence of advanced abutment pressure(secondary mining)during the mining of the working face,the deformation of surrounding rock in the advanced supporting section of auxiliary transport roadway is serious,which restricts the safe and rapid mining of the working face.The thesis takes the auxiliary transportation roadway of the 3-1 coal face of Cuncaota No.2 Mine as the research object,around its characteristics of being influenced by double mining,by using the methods of laboratory test and field measurement,the mechanical property parameters of coal rock and the evolution law of surroundings rock fissure are measured in the auxiliary transport roadway of 3-1coal working face.The geomechanical properties of surrounding rock and the development and distribution law of internal fissure in surrounding rock after primary mining are obtained,which provides a basis for the optimization design of the original primary support scheme of roadway.Based on investigation of the deformation characteristics of auxiliary transport roadway in 31204 and 31205 working face in the early stage,and aiming at the auxiliary transport roadway in 31206 working face,the mining pressure law of roadway in the secondary mining process before and after is studied by using the numerical calculation method,taking the diameter,length and row spacing of anchor rod and cable as the main factors.The distribution and evolution of the vertical stress,surface displacement and plastic zone of the surrounding rock in the advance section of auxiliary transport roadway under different support technology schemes are analyzed.The reasonable primary support scheme and main technical parameters of the roadway are optimized,and the reinforcement support scheme and parameters before secondary mining are proposed.The results of the research were tested in the field.The monitoring of mine pressure law in the field system shows that the new support scheme can effectively solve the supporting problem of auxiliary transport roadway in the doubleroadway layout working face of Cuncaota No.2 mine,and provide guarantee for the safe and efficient production of the working face,and create good technical and economic benefits.The thesis has 77 figures,15 tables and 71 references.