Bolting technology of serious swelling soft rock roadway

Abstract

For reducing the large roof deformation and bolt failure problems in serious swelling and soft rock roadway, influence factors of roadway stability and bolting technology in serious swelling soft rock roadway are studied based on engineering analogy analysis and numerical simulation. Research results show that the low strength of soft rock roof, easy swelling and softening of water are the internal causes of roof failure and instability. The external causes are high concentration stress of surrounding rock and insufficient supporting strength. The roadway stability can be improved by optimizing the layout of roadway and strengthened support. The combined bolting scheme of resin extended anchor bolt and cable in serious swelling soft rock roadway is determined, and the row spacing is 800 mm×900 mm, the pre-tightening torque of bolt is not less than 400 N·m, and the row spacing between cables is 1 600 mm×1 800 mm, and the anchor cable preload is 200-250 kN. The bolting scheme has been tested on the field, good supporting effect has been achieved.

Keywords

• serious swelling soft rock
• unstable failure
• bolting
• numerical simulation
• roadway support