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基于Hoek-Brown岩体失效准则，根据开挖空间围岩变形压力与收敛的关系，导出了圆形隧道围岩荷载计算公式，然后利用隧道非规则断面等价圆算法，将其拓展成任意断面隧道围岩荷载确定方法。在分别建立起锚杆、喷射混凝土及钢拱架等支护单元特征函数的基础上，基于并联模型导出了锚喷组合支护结构刚度、抗力计算公式。根据开挖面的空间效应建议了支护特征曲线起点确定方法。利用上述成果，结合收敛-约束原理构建了支护结构稳定性系数计算方法，克服了基于岩体分级类比的地下结构支护设计方法不能定量评价其安全程度的缺陷。通过案例分析，示范了所构建方法的操作和运行过程，并初步验证了其有效性。“,”According to the relationship between deformation pressure and convergence of surrounding rock of excavation space, a formula for load of the surrounding rock for a circular cross section tunnel is deduced based on the Hoek-Brown failure criteria. Then it is extended to non-circular cross section tunnels using the equivalent circle method for tunnels. The formulae for the stiffness and resistance of composite supporting structures, which are composed of shotcrete, bolt and steel arch, are constructed based on the parallel model after the characteristic function for the supporting units (anchor, etc.) is deduced. A method to determine the starting point of the curve of the supporting structures is suggested according to the space effect of the tunnel surface. Based on the above-mentioned results, an approach for stability coefficient of the supporting structures is established considering the convergence-confinement method. The approach overcomes the defect that the empirical design method for the supporting structures based on rock mass classification cannot quantitatively evaluate safety degree of the supporting structures. Finally, the operation process of the proposed method is demonstrated through analysis of a case history and its validity is tested and verified preliminarily.