Abstract: According to the problem of frequent rock burst in driving process of lower roadway of 2113₂ work face in Changcun mine，the factors for rockburst is analyzed，that is，the superposition of the high stress of Z Coal pillar results in frequently rock burst.The numerical simulation software FLAC^3D is adopted to analyze the stress superposition level and the stress distribution in Z-type coal pillar zone.At the same time，the optimization analysis on the roadway arrangement for the No.21 mining area is made.The proposals for the buffer arrangement of roadway system for three working faces are put forwards，by considering the aspects from how to avoid stress concentration and the maximum recovery of coal resources.And their advantages and disadvantages are analyzed to finally determine that the second one is optimal.This research provides a solid basis for the safe recovery of the bottom slicing workface.

Key words: Z type coal pillar, Rock burst, FLAC^3D, Stress superposition, Reduced impact optimization