中文摘要：

科学、合理的表征塑性区几何形态特征是定量分析评价围岩稳定性的重要基础.基于非对称圆巷塑性区边界解析式,探讨了塑性区随双向压力比的形态演化律及分布特征.在此基础上,应用几何形态学理论,建立了由第Ⅰ类与第Ⅱ类指标共同组成的圆巷塑性区形态特征指标体系.深入分析了各形态指标的内涵、差异及其与围岩稳定性的关系.结果表明,塑性区随双向压力比演变为蝶形、长叶蝶形后,各方位的塑性扩展深度均匀性显著减小,塑性区面积的增速远大于极限塑性扩展半径,且塑性区X寸的变化更敏感,因此,在（超）高偏应力环境下,巷道愈发容易失稳破坏.均匀系数及形状不规则系数均可刻画塑性区形状均匀性、规则性特征,但采用形状不规则系数进行表征更能反映形态的变化差异.最后通过算例分析验证了各指标的科学性及合理性,为巷道围岩稳定性定量评价及围岩分级奠定了指标基础.

英文摘要：

The important basis for quantitative analysis and evaluation of surrounding rock stability is that morphological characteristics of plastic zone are scientifically and reasonably represented. In this paper, based on analytical formula of plastic zone boundary of asymmetric circular roadway, the evolution law and distribution of plastic zone morphology with biaxial pressure ratio are discussed. On this basis, the index system for morphological characteristics of plastic zone around circular tunnel is established by using theory of geometric morphology, which is composed of class Ⅰ and class Ⅱ indexes. The connotation, difference of each index and the relation between surrounding rock stability and indexes are analyzed. Results show that after plastic zone evolves into butterfly-shape, butterfly - shape with long leaf with change of biaxial pressure ratio, uniformity of plastic expansion depth at all directions decreases obviously. Meanwhile, growth of plastic zone area is much greater than that of limit plastic expansion radius, and the change of plastic zone size is more sensitive. So in （ super） high deviatoric stress environment, roadway is easy to fail. The uniformity coefficient and irregular coefficient of shape can be used to describe the characteristics of uniformity and regularity of plastic zone shape. But coefficient of irregular shape can better reflect difference of morphologic change. Finally, an example is given to verify the scientificity and rationality of the indexes, which lays a good foundation for quantitative evaluation and classification of surrounding rock stability.