城市地铁隧道的修建常遇到下穿建筑物施工的情形。隧道施工扰动四周地层，使其下穿的建筑物产生变形和附加内力，其中危害较大的为倾斜、弯曲以及水平拉伸变形，实际过程当中常常出现复合变形的特点。这些变形和附加内力会直接影响到既有建筑物的安全使用。为了确保地铁隧道施工安全有序进行，迫切需要对浅埋暗挖法隧道下穿建筑物的施工技术进行研究。 本文选择西安地铁三号线韩森寨～通化门区间浅埋暗挖段隧道下穿金花酒店为工程实例，辅以MIDAS/GTS数值模拟计算，预先对隧道施工过程中围岩的变形规律进行预测，从而有针对性的制定施工方案。具体的研究工作与结果如下： （1）分别采用台阶法、留核心土法以及全断面法进行模拟分析对比，得出上下台阶留核心土法开挖更加适合工程实践；此外通过选取不同的锚杆参数、不同的开挖进尺以及采用不同的加固措施，然后对几种数值模拟的位移场进行分析对比，得出西安地铁隧道浅埋暗挖法最佳的施工设计方案。 （2）采用台阶留核心土的方法对隧道进行开挖，并对工程进行现场数据监测得出建筑物的最大沉降 15mm，符合规范要求。通过分析对比数值模拟结果与现场监测数据，得出实测拱顶位移值、拱腰水平收敛值、建筑物沉降值与数值模拟的拱顶沉降和水平收敛值以及建筑物沉降值比较接近，误差 5%，验证了数值模拟对实际工程有很重要的指导作用。 （3）介绍了四种隧道下穿过程中既有建筑物的保护方案，并结合具体实际得出注浆加固法更加适合建筑物的保护。最后对既有建筑物的保护进行方案设计。

In dense urban construction of shallow tunnel, the situations of undergoing through buildings are so common. Tunnel excavation process will inevitably disturb the surrounding formation, resulting in generating additional internal forces and deformation to the undergoing buildings. Under the existing building through the construction process, the deformation features are: bending deformation, settlement, horizontal deformation, tilt deformation, in which the building is more harmful to tilt, bend and stretch horizontally, the actual process often complex deformation characteristics appear. thus affecting normal use and safety of existing buildings. In order to ensure a safe and orderly construction of shallow tunnel, meanwhile do not affect the safe use of existing buildings, the need to study the impact of shallow tunnel construction undergoing existing buildings is urgent. In this paper, we choose Xi'an Metro Line 4 Hansen Village ~ Tonghua door tunnel beneath the Golden Flower Hotel as background, to study the tunnel through Midas / gts numerical simulation and the use of surface-site monitoring data . Expand research work and results are as follows: (1) Step method was used, leaving the core of the simulation analysis and comparison of indigenous and full-face method, draw up and down stairs is more suitable to stay Core Soil excavation engineering practice; Moreover, bolt by choosing three different parameters, different open dig footage and different reinforcement measures, and several numerical simulation analysis and comparison of the displacement field, the Xi'an Metro Shallow Tunneling Method construction design can be made. (2) The data (≤15mm ) is obtained after the monitoring from the project site, which meet regulatory requirements. To ensure the normal engineering construction, does not affect the safe use of existing buildings. We analyzed by comparing simulation results with field monitoring data, results measured displacement values vault, vault settlement and horizontal convergence value hance level convergence value and numerical simulation are close error of <5%, to verify the numerical simulation of the actual project has a very important role in guiding. (3) Describes four schemes to protect the existing buildings when the undergoing method was taken. Combined with the actual results grouting concrete reinforcement method is more suitable for the protection of the building. In the end, a more suitable design to protect existing building will be on progress.