ABSTRACT
According to numerous studies on the rational section coal pillar, many effective methods to determine the reasonable size of coal pillars can be categorized as follows (Cui et al. 2012, Tu et al. 2011, Zhang & Shi 2004, Chen 2014, Shao et al. 2014): 1) Mathematical statistics, a large number of measured results give rise to inductive reasoning that unstable surrounding rock conditions of coal pillar size; 2) Application of mine pressure regularity with various coal pillar and empirical formula to analyze the reasonable size of the coal pillar; 3) The reasonable coal pillar width range determined based on measured pillar abutment pressure distribution method analysis of coal seam; 4) According to the limit equilibrium theory to derive the coal hold steady when the width formula; 5) The estimation formula of three dimensional plastic zone width of coal pillar stress. The numerical simulation of roadway surrounding rock is performed to analyze the width of coal pillar under different stress and movement for working face 222203 in Shuangxin Mining Co. coal mine, Inner Mongolia.
