Study And Application Of Surrounding Rock Control Technology For Small Coal Pillar Support With Steep

The deformation and failure of surrounding rocks in roadway with steep has significant asymmetric and unbalanced characteristics.The component force of gravity along the structure plane will increase due to the large dip angle of coal seam,which can easily lead to slip along the plane,thereby resulting in the damage-deformation the roadway is serious and its maintenance is also difficult.In this paper,based on the background of headgate of panel 2918 in Zhubai coalmine,a mechanical model of small coal pillar support with steep coal seam mining is established.A numerical simulation method FLAC-3D is applied to analyse the deformation of support during different periods,including roadway excavation,coal mining with upper panel,and coal mining with lower panel.Then the deformation mechanism of the small coal pillar support with steep coal seam mining is studied in detail.Meanwhile,according to the strata behaviors with the existing support of roadway,the deformation mechanism of the small coal pillar support is studied systematically.Finally,the control technology of the small coal pillar support with steep is further studied based on the geological condition and mechanical characteristics of panel 291 8,and the design of the initial support scheme is optimized;and then a new support scheme of the small coal pillar support condition with steep is put forward.It shows that the deformation of roadway with the new optimized support scheme(i.e.bolt-mesh-cable support)decreases notably with the coal mining of lower panel,and the amount is reduced to 30%through numerical simulation and field observation.It indicates that the support effect of the roadway is better and the support parameters are reasonable.