Study On Powerful Restraint Of Fully Mechanized Small-Pillar Mining And Deformation Controlling Of Roadway Surrounding Rock

Pillar is generally used in the field of coal industry in our country in order to protect roadway affected by mining, which provides a reliable method for the guarantee of coal mine safety, which is simultaneously one of the important technical means for the construction of high output and high efficiency mine. With regard to the current application situation of mining roadway with pillar, some difficulties exists in the ascertainment of design about width of coal pillar, the surrounding rock deformation control and security problem. It is, therefore, propitious to further promoting the development of the technology of pillar protection roadway to carry out research on mining with the strong constraint of small coal pillar and surrounding rock deformation control, thus exerting vital scientific and guiding significance in increasing the mining rate of coal resources and ensuring the safety of coal roadwayShenhua Ningxia Coal Group Baijigou Mine is selected as the study object because the coal mining method of pillar protection roadway for this mining area is not mature and the coal pillar width is chosen through experience, which cannot ensure the stability of roadway and construction safety. Consequently,2621 working face of Baijigou Mine is considered as the engineering background to discuss the contents as follows:(1) Reasonable width of coal pillar and support scheme of roadway, via investigation and collecting information on site, in consideration of specific condition of 2621 working face, are put forward.(2) Given coal pillars with hollow grouting anchor cable, the combined reinforcement scheme "anchor+metal mesh+shotcrete+hollow grouting anchor cable to reinforce pillar" is put forward.(3)The elastic zone width and the plastic zone width of coal pillar by theoretical calculation obtained, stress distribution and displacement variation law of roadway surrounding rock are simulated by FLAC3D under the condition of different coal pillar widths. Through comparative analysis on the theoretical calculation results and the simulation results. we draw the conclusion that the reasonable coal pillar width of Baijigou Mine is 30 m.(4)The results, through the field monitoring, show that the support scheme increase the strength of coal pillar, thus ensuring the overall stability of surrounding rock of roadway and safe production.