Abstract: In view of the situations of No.3045 working face in Wangzhuang coal mine,such as large span of roadway,broken coal seam,and large deformation of roadway,the characteristics of the deformation and stress of roadway surrounding rocks with large mining height and narrow coal pillar is analyzed in order to improve the control ability of roadway.Through the limit equilibrium theory,the coal pillar size is reasonably determined,and the control mechanism of roadway surrounding rock with large span and broken seam is analyzed.Then,combined with the actual situation of No.3045 working face in Wangzhuang mine,the corresponding technical solutions for surrounding rock control is given.Since the original bolting program has not adapted the requirement of surrounding rock control,the original supporting parameters are optimized with application of orthogonal method and numerical simulation.The observation on displacement of roadway surface and deep roadway indicated that:maximum displacement of the roadway surface along goaf is 230 mm,maximum displacement during mining is 1 049 mm.These variations in the practical project are within the allowable range.Engineering practice has proved that this support technology has a significant effect on surrounding rock control.The research result provides guidance for controlling surrounding rock with large-span and broken seam and selecting the supporting parameters.

Key words: Large mining height, Narrow coal pillar, Broken coal seam, Combined support , Surrounding rock control, Orthogonal experiment