针对引水隧洞斜井、井底车场与正洞交叉段整体施工围岩变形不易控制的问题，以滇中引水工程楚雄段施工8标龙潭2#支洞转正洞工程为载体，采用FLAC 3D建立数值模型进行隧洞施工数值模拟，分析隧洞施工过程中不同区域的位移变化规律，找出主要不利影响区域，提出合理施工方案，并与实际监控量测进行对比分析。结果表明： 1）隧洞开挖初期变形速度最快且隧洞开挖后围岩变形量随隧洞断面的增大而增大； 2）主支洞交叉段围岩结构稳定性较差，围岩位移量最大，位移最大位置在交叉段中间主支洞连接处，且交叉段主洞右侧围岩受到井底车场施工影响，结构稳定性减弱，左拱腰呈现出外扩的变形特征； 3)针对交叉段的施工采用小导洞施工法并加强支护且在交叉段附近单方向施工能有效提高交叉段围岩稳定性。

 The deformation of surrounding rock is not easy to be controlled in the integral construction of inclined shaft, shaft station, and main tunnel crossing section of water diversion tunnel. Based on the intersection of  Longtan #2 branch tunnel and main tunnel project of Chuxiong section, No. 8 bid of Central Yunnan Water Diversion Project, a numerical model is established by FLAC 3D to simulate the tunnel construction process. The displacement variation law of different regions in the process of tunnel construction is analyzed, the main adverse influence area is found out, and the reasonable construction scheme is put forward and compared with the actual monitoring and measurement. The results show that: (1) The deformation speed is the fastest at the initial stage of tunnel excavation and the deformation of surrounding rock increases with the increase of tunnel crosssection after tunnel excavation. (2) The structural stability of the surrounding rock at the intersection of the main and branch tunnels is poor, and the displacement of the surrounding rock is the largest; The maximum displacement is located at the connection of the main and branch tunnels in the middle of the intersection, and the surrounding rock in the right of main tunnel at the intersection is affected by the construction of the shaft station, leading to the result that the structural stability is weakened, and the left arch waist shows the deformation characteristics of outward expansion. (3) The stability of surrounding rock in intersection area can be effectively improved by using small pilot tunnel construction method, strengthening support, and single direction construction near the intersection.