基于DrukerPrager准则的煤层冲击失稳模型.pdf

摇 第36卷第5期 煤摇 摇 炭摇 摇 学摇 摇 报 Vol.36摇 No.5摇 摇 2011年 5月 JOURNAL OF CHINA COAL SOCIETY May摇 2011摇 摇 摇 文章编号:0253-9993(2011)05-0727-05 基于Druker鄄Prager准则的煤层冲击失稳模型 姜福兴,刘金海,王摇 平 (北京科技大学 土木与环境工程学院,北京摇 100083) 摘摇 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鄄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鄄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。 关键词:Druker鄄Prager 准则;煤层冲击失稳;屈服准则;冲击地压 中图分类号:TD324郾1摇 摇 摇 文献标志码:A Model of coal burst and instability based on Druker鄄Prager yield criterion JIANG Fu鄄xing,LIUJin鄄hai,WANG Ping (Civil Environmental Engineering School,University of Science Technology Beijing,Beijing摇 100083,China) Abstract:Yield criterion has great influence on resultsby 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 byusingDruker鄄Prageryieldcriterion.Analyticalformulasfor stressesinseam,disturbedarealengthandplas鄄 tic area length are obtained,and the results by these formulas are compared with that by Mohr鄄Coulomb yield criteri鄄 on.The influences of support resistance,in鄄situ rock stress and roadway爷s size on the coal burst and instability were discussed.The conclusions are drawn asfollowing:the stress distribution curves obtained by the method have obvious characteristics ofthetypical stressdistributionincoal seam;theevaluationresultforcoalburstandinstabilitybyusing the Druker鄄Prager yield criterion is more reliable;strengthening supporting aswell asreducing ratio of width to height of the roadway is beneficial to control of burst