为解决特长引水隧洞洞内带状平面控制网精度难以提高、横向摆动和贯通误差大等问题，结合新疆某特长引水隧洞洞内平面控制测量的实际情况，设计一种混合固定测站和自由测站观测值的隧道洞内平面控制测量新网形。首先，利用计算机模拟仿真的方法生成该平面控制测量网形的模拟观测值，经过相应处理可以估算出隧道洞内横向贯通误差； 然后，按照设计网形对该引水隧洞洞内平面控制网进行实际测量。实测结果表明，采用该网形观测得到的洞内平面控制网，各项精度指标均能满足隧道二等要求，并且根据实测数据估算的洞内横向贯通精度与仿真计算结果较为接近，从而验证了所采用的仿真计算方法用于估算隧道洞内平面控制网精度的可行性和可靠性。

A case study is conducted on a superlong waterdiversion tunnel in Xinjiang, China, to address the many disadvantages of the current plane control network, such as low precision, large lateral swing, and penetration error. A novel plane control measurement network is designed based on observations from fixed and free measurement stations. Computer simulation is used to generate simulated observation values for the network, and the transverse penetration error in the tunnel is estimated after processing. The designed network is then used to measure the actual plane control network in the tunnel. The results show that the precision indices of the tunnel plane control network obtained by the recommended network can meet the secondary requirements of the tunnel, and the precision of transverse penetration estimated from the measured data is close to the simulation results, validating the feasibility and reliability of the simulation calculation method in estimating the precision of the plane control network in a tunnel.