Research on reasonable staggered distance along strike of simutaneous mining faces in shallow seams

In order to ensure high intensity and safety mining of shallow seams, aimed at the safety and technical problems in the upper and lower coal seam simut aneous mining at production site, research method of combining UDEC numerical simulation and theoretical analysis were used to study the shallow seams of typical 0 ccurrence condition.The results obtained that the surrounding rock stress distribution regularity of lower seam face and the law of surface subsidence in different stagge red distance along strike. The influence extent and influence degree of upper and lower coal seam working face were analyzed. Stable pressure and reduced pressure models in imultaneous mining faces of upper and lower were established. Considering the practical experience of mining, the paper gave the calculation formula of two kinds of arrangement. The results showed that the stress of surrounding rock in the lower coal seam face was greatly affected by the upper coal seam mining when the upper and lower coal seams was simultaneously mined, and the safe mining could be achieved by using the stable pressure arrangement.