【摘要】 为评价煤柱的长期强度和长期稳定性,以弹粘塑性理论和统一强度理论为基础,结合煤柱应变软化的概念,对煤柱塑性区进行了专门探讨,得到了煤柱弹性区和粘塑性区的应力分布、位移分布以及粘塑性区宽度的理论公式。分析了界面摩擦角、煤柱抗压强度、煤柱高度、覆岩压力、屈服准则的选取等因素对粘塑性区的影响,部分实验结果得到了理论解释。此外还探讨了开采时所需留设的合理煤柱尺寸,并给出了开采时应注意的几个问题。更多还原

【Abstract】 To evaluate the long-term strength and stability of a pillar,the pillar’s stress and displacement distributions and the width of visco-plastic zone based on elasto-visco-plastic theory and unified strength theory are presented theoretically in this paper combined with the concept of strain softening.The effects of several major factors,such as interface friction angle,pillar’s compressive strength,underground pressure and the selection of yield criterion et al,on the width of visco-plastic zone are analyzed in detail.Some experimental results are explained.The proper size of pillar is discussed and several problems concerning mining methods are also pointed out.更多还原