本文对几个小型构造型式张裂隙组合运用了数理统计分析进行研究,结果证明用一元线性函数表示的等距性原理不能正确表示岩石构造裂隙组合的疏密变化规律,且计算误差大;证明用正态分布函数能表示岩石构造裂隙组合的疏密规律,且计算误差小。最后,作者提出了关于用非线性分布函数表示的等距性原理的新概念。 In this paper, mathematical statistics analysis is used to study the combination of several small structural types of fractures. The results show that the isometry principle represented by a linear function can not accurately represent the density variation rules of rock structure fracture combinations, and the calculation error is large; The normal distribution function can represent the compactness law of rock structure fracture combination, and the calculation error is small. Finally, the author proposes a new concept about the isometry principle represented by a nonlinear distribution function.