Study on Combination Supporting Parameters Optimization of Rock Bolting-arch in Soft Rock Roadway

In order to seek optimal supporting parameters of rock bolt and arch supporting,and verified failure mechanism of rock bolt-arch supporting in soft rock roadway,it taking typical soft rock roadway as engineering background,and refining numerical simulation platform FLAC^3D was applied,which include the following characters rockbolt broken,arch bending yield and frame-rock separation,and then comparative studying of surrounding rock control effect by different intensity combination with rock bolt and lagging jack.The results showed that firstly roadway convergence deformation amount and plastic zone area all decreased with rock bolt diameter and lagging jack sectional area increased,but with small influence to floor heaving,the second,seriously rock bolt broken and lagging jack bending yield appeared under independent action of rock bolt or lagging jack,but results improved under synergy action.The third,the main inducing reason of lagging jack failure was lagging jack leg deformation under components failures mechanism analysis.The fourth,according contrastive analysis of different supporting intensity combination,but rock bolt diameters had less influence to supporting results,but obviously with lagging jack parameters variation.The optimization supporting means that 18mm+1.2U36 with addition arch locking bolts was put forward,and then verified in field.