摘要
基于孔隙煤体SEM结构分析,在煤本构模型中引入损伤参数,结合煤块单轴应力-应变试验曲线,对煤体峰后应变软化性能与表征煤强度分布特征的Weibull参数之间的关系进行了探讨,得到Weibull参数m值与煤峰值强度后线性降模量λ之间的拟合关系,反映了煤体损伤程度对其峰后应变软化的影响。并基于能量原理,分析出煤体峰后应变软化是采煤工作面发生冲击地压的必要条件,将孔隙煤体的本构关系简化为双线性应力应变关系,结合工程实例计算了发生冲击地压时煤体峰后应变软化的临界范围与Weibull参数取值范围,对孔隙煤体峰后应变软化及其对冲击地压的影响程度做出了定量评价。
Based on the SEM pores structure of coal, by introducing damage parameter into the coal constitutive model and combining with coal uniaxial stress-strain test curve, discussed the mutal relationship between coal post-peak sof-tening and Weibull parameters that reflected strength characteristics of coal and explores the relationship between m value of Weibull parameters and the the linear modulus A value of post-peak strength, reflected the influence of dam- age degree to post-peak strain softrning in porosity coal. Besides, analyzed that post-peak softening was a necessary condition of coal face rock burst occurred based on energy theory, by simplifing bilinear constitutive relationship between stress and strain, calculated the critical range of A value of post-peak softening and the critical range of m value of Weibull parameters when rock burst occurred with an engineering example. Finally, made a quantitative evaluation on influence degree of post-peak softening to rock burst.
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2010年第12期1990-1996,共7页
Journal of China Coal Society
基金
国家重点基础研究发展计划(973)资助项目(2010CB226802)
国家自然科学基金资助项目(50879049
50574064)
