It is important to accurately predict rock bursts in unexcavated tunnel sections for the safe and rapid construction of tunnels.Aiming at the characteristics of tunnel rock bursts,a unified solution to the stress of the cir-cular section under the effects of lateral pressure is obtained by a complex variable function solution proposed by Muskhelishvili and based on conformal mapping function represented by the Laurent series of infinite single con-nected domain.With proper criteria for rock bursts,a comprehensive assessed grade of rock bursts is determined,and a comparison of the calculation results,numerical simulation results and actual results of rock bursts is conducted. The results show that:1)stress concentrations with different degrees occur at different parts of the surrounding rock, and the maximum compressive stress mainly occurs at the crown after excavation;2)stress concentration and abrupt change could occur at the structural surface after excavation of a deep-buried tunnel section due to the effects of tec-tonic stress;and 3)the analytic calculation results and numerical simulation results agree well with the actual re-sults of rock bursts,which demonstrates the effectiveness of this analysis method with complex variable function.%岩爆的准确预测对隧道的安全、快速施工具有重要的意义.文章针对隧道岩爆特征,借助共形映射函数,以无限单连通域的Laurent级数表示的映射函数为基础,应用Muskhelishvili提出的复变函数解法得出侧压力作用下圆形断面的应力统一解;选择合适的岩爆判据,得出岩爆综合评定等级,并将解析计算的结果与数值模拟计算得出的岩爆结果及实际岩爆情况进行对比分析.结果表明:隧道围岩的不同部位出现不同程度的应力集中,开挖后的最大压应力主要位于拱顶处;深埋隧道段围岩开挖后,受构造应力影响的结构面应力会出现突变及应力集中;解析计算结果与数值模拟和实际岩爆结果基本吻合,证明了借助复变函数分析岩爆预判的有效性,对施工有一定的指导作用.
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