【摘要】 屈服准则对煤层冲击失稳模型的计算结果有较大影响。考虑中间主应力和支护阻力的作用,运用Druker-Prager准则对煤层平动冲击失稳模型进行推导,得到煤层应力、扰动区长度、塑性区长度的解析公式,并与基于Mohr-Coulomb准则的计算结果进行对比,分析支护阻力、原岩应力、巷道尺寸对煤层冲击失稳的影响。结果表明,此方法得到的煤层应力分布曲线符合典型的煤层应力分布特征,且其煤层冲击失稳评价结果更加可靠;加强支护和减小巷道宽高比,能够降低深部煤层发生冲击失稳的危险。更多还原

【Abstract】 Yield criterion has great influence on results by model of coal burst and instability.Taking into account the functions of the middle principal stress and the support resistance,the instability model of translatory coal burst was derived by using Druker-Prager yield criterion.Analytical formulas for stresses in seam,disturbed area length and plastic area length are obtained,and the results by these formulas are compared with that by Mohr-Coulomb yield criterion.The influences of support resistance,in-situ rock stress and roadway’s size on the coal burst and instability were discussed.The conclusions are drawn as following:the stress distribution curves obtained by the method have obvious characteristics of the typical stress distribution in coal seam;the evaluation result for coal burst and instability by using the Druker-Prager yield criterion is more reliable;strengthening supporting as well as reducing ratio of width to height of the roadway is beneficial to control of burst and instability of the deep coal.更多还原