盾构法是目前城市轨道交通建设施工中的主要方法之一。鉴于盾构在施工过程中不可避免地会遇到近距离下穿既有建筑物的情况，使其有沉降、倾斜、拉伸、压缩变形等潜在风险，尤其是地铁车站及风道，有必要对其影响进行风险评估及施工控制。以北京地铁8 号线盾构区间隧道下穿地铁14 号线车站的东南风道为例，在对施工风险进行评估的基础上，借助有限差分软件对施工过程进行了动态模拟，分析了盾构施工引起的地层位移、应力及其对邻近风道结构的影响，并提出了加固土体、控制盾构参数、加强二次注浆等控制措施，以减少对邻近风道的影响。现场监测结果表明，在采取有效控制措施后，风道结构最大变形被控制在2mm以内，从而验证了所提方案的合理性。

The shield method is one of the main methods in metro construction. In the process of construction, it is unavoidable to encounter situations that the shield machine has to pass underneath existing buildings in close distances, which may has potential impacts on buildings, such as settlement, tilt, tension, compression deformation, etc., especially for subway stations and wind tunnels. Therefore, it is necessary to carry out research on this corresponding risk assessment and construction control measures. The internal tunnel of Beijing Subway line 8 passing underneath the southeast air duct of Yongdingmen outside station of Subway Line 14 was taken as an example, and the construction risk was assessed firstly. Subsequently, the finite-difference software was used to simulate the construction process, and the ground displacement and stress caused by shield construction and its influence on the structure of adjacent air ducts were analyzed. The reinforcement of soil mass, control of shield parameters, grouting and other control measures were proposed to reduce the impact on adjacent air ducts. The monitoring results show that the maximum deformation of air duct structure was controlled within 2mm after adopting effective control measures, verifying the rationality of the proposed scheme.