基于黏性材料Lade-Duncan破坏准则，分析煤柱应力规律，将小主应力σ3看成是开采前的静水原岩应力推导出煤柱强度计算式，并与M-C准则，A. H. Wilson计算式结果相比较.经分析比对发现，没有考虑中主应力的M-C屈服准则，A. H. Wilson公式结果都偏小，且A. H. Wilson结果过分偏低，而考虑中主应力的Lade-Duncan破坏准则却在煤柱强度计算结果上明显存在优势，更合理.从内摩擦角和黏聚力这两个角度出发，讨论其对煤柱强度特性的影响规律及影响程度，结果表明煤柱极限强度受二者影响显著，且前者影响程度大于后者.%Based on the Lade-Duncan failure criterion of coherent material,the formula of limit strength of the coal pillar is derived by analyzing the stress discipline of the coal pillar and considering the minor principal stress σ3 as hydrostatic stress pre-mining. Compared with the limit strengths of the coal pillar using the Mohr-Coulomb failure criterion and the simplified A. H. Wilson formula,it shows that the results of the Mohr-Coulomb failure criterion and the simplified A. H. Wilson formula are small,which do not consider the intermediate principal stress,but the the results of Lade-Duncan failure criterion which considers the principal stress have evident advantages and are more reasonable. From the two respects of the internal friction and cohesion,the discipline and degree of the internal friction and cohesion influencing on the pillar strength characteristics are discussed. The results indicate that the limit strength of the coal pillar is significantly affected by them,and the former is greater than the latter.
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