摘要
Abstract
Affected by factors such as excavation and mining disturbance,coal seam occurrence conditions and surrounding rock characteristics,broken surrounding rock roadway has gradually become one of the hidden dangers that restrict the safe and efficient production of coal mines.To solve the problem of supporting broken surrounding rock in the 3304 second return air crossheading of Sangshuping No.2 shaft.The methods of theoretical analysis,laboratory test,numerical simulation and industrial test are used.The orthogonal experiment of influential factors of grouting materials was carried out,and the grouting pressure was numerically simulated.The prestressed grouting reinforcement support technology system is proposed.The experimental results show that the optimal ratio of grouting materials is clay-cement mass ratio of 1∶1,expansion agent content of 10%,silicon powder content of 6%,accelerator content of 2.9%,water reducing agent content of 2.5%,water-cement ratio of 0.45,and grouting pressure of 3.0 MPa.Aiming at the support problem of 3304 second return air roadway in Sangshuping No.2 shaft,the pre-stressed grouting reinforcement support technology is put forward,which improves the integrity of broken surrounding rock roadway and solves the support difficulty of broken surrounding rock roadway.The practical application shows that five high pre-stressed grouting bolts are arranged in each row of the side,the grouting pressure is 3 MPa,and the convergence of the roof and floor of the 3304 secondary return air crossheading and the two sides is 105 mm and 86 mm,respectively.The pre-stressed grouting reinforcement effect is good,the bond strength of the broken surrounding rock is enhanced,and the integrity is improved.关键词
巷道支护/注浆加固/破碎煤体/围岩控制/预应力注浆Key words
roadway support/grouting reinforcement/fractured coal/surrounding rock control/prestressed grouting分类
矿业与冶金
