Abstract:
In response to the difficult problem of the stability control of the surrounding rock during the rapid excavation of coal roadways under the conditions of high ground pressure, high ground temperature, and strong impact-prone coal seams, taking the 3409 transportation crossheading of Shaanxi Zhengtong Coal Mine as the engineering background, through theoretical calculations and FLAC
3D numerical simulations, the distribution law of the plastic zone of the roadway surrounding rock and the characteristics of stress evolution were studied. The research results show that: the width of the plastic zone on both sides calculated theoretically is 2.78 m, and the numerical simulation shows that the width of the plastic zone on both sides is 2.5 m, and the width of the plastic zone of the roof and floor is 4.5 m. The vertical stress of the roof is distributed in a butterfly shape, and there is a stress erosion phenomenon at the bottom corner of the floor. Based on this, the support parameters of bolts and cables were optimized (the row spacing of roof bolts was adjusted from
1000 mm×
1100 mm to 950 mm×
1200 mm, and the row spacing of roof cables was adjusted from
1200 mm×
1200 mm to
1500 mm×
1100 mm), and on-site industrial tests were carried out. The monitoring results show that after optimization, the maximum separation amount of both sides decreased from 146 mm to 43.2 mm, and the maximum separation amount of the roof and floor decreased from 282.5 mm to 76.2 mm. The control effect on the deformation of the surrounding rock is remarkable.