隧道建设过程中，掌握隧道围岩中裂隙的分布及连通性情况，对于合理选择施工方法和支护方案等环节至关重要。从隧道建设的需求出发，建立岩体的三维裂隙模型，并对裂隙的连通性进行分析。基于现场实测裂隙各项参数服从的分布规律，采用蒙特卡洛算法模拟产生裂隙的三维数据，使用空间薄圆盘表示裂隙，生成裂隙的三维模型。通过与竖向钻孔数据对比，对基础模型进行修正（筛选），找到最符合实际情况的模型。之后，运用空间几何原理，通过圆盘之间的相互关系分析裂隙的连通性，并运用C++编程实现连通性判别计算。通过建立一种从分析任意2个圆盘之间几何关系入手的连通性分析方法，实现裂隙的连通性分析。

In the process of tunnel construction, knowing the distribution and connectivity of cracks in surrounding rock around tunnel is crucial to select reasonable construction methods and supporting schemes. Based on the requirements of tunnel construction, a threedimensional fractures model for rock masses is established and the connectivity of fractures is analyzed. Based on the distribution laws of parameters of insitu fractures, Monte Carlo simulation is adopted to generate threedimensional data for fractures, which are represented by spatial thin disks and then the threedimensional model for fractures is formed. Compared to the test data from vertical drillings, the proposed model is modified (screened) to accord with the actual situation. Then, by using the principle of space geometry, the connectivity of fractures is analyzed through the interrelationship between two disks. After that, C++ is used to realize the calculations in the connectivity analysis. The paper presents a method of connectivity analysis for analyzing the interrelationship between any two disks and realizing the connectivity analysis of cracks.