摘 要 本文通过Midas/GTS数值模拟和现场监测两种方法对在隧道结构参数确定的情况下，浅埋暗挖不同工法穿越地裂缝前后各断面上隧道内部和轴线对应地表的变形量和变形规律进行了研究,并提出控制变形的施工技术措施。论文得到以下结论： （1）上下台阶法在远离裂缝段开挖土体时，隧道拱顶和地表的沉降不受地裂缝影响。CRD法开挖时，裂缝影响区段内的变形沉降量明显要比上下台阶预留核心土开挖远离裂缝段拱顶的沉降变形量大。CRD法穿越地裂缝的过程中，裂缝的影响区域内的地表沉降量受水的影响较大，故应做好防排水的具体施工措施，避免在雨天穿越裂缝处。 （2）裂缝影响区域内拱腰处的最终收敛量和收敛速度都要大于远离裂缝拱腰处的最终收敛量和收敛速度，各断面上的最终收敛量满足安全需求。上下台阶预留核心土法和CRD法转换进行施工时，地裂缝对拱腰处的变形无太大影响。 （3）CRD法开挖时，衬砌结构的受力并不对称，靠近裂缝处拱顶的应力要大于裂缝远处拱顶的应力。 （4）开挖裂缝临近土体时，整体采用CRD法向前推进，局部左右侧4部分导坑土体采用上下台阶预留核心土开挖后，地表的最大沉降量减小了5mm左右；同时设置分缝衬砌结构、做好裂缝处的防排水措施及采用二重管注浆固结地层等措施可降低地表的沉降量。

The paper analysis the law of deformation and the deformation quantity of the surface corresponds to the tunnel axis and the interior of tunnel that is not crossing and crossing ground fissure by means of software Midas/GTS numerical simulation and in-site monitoring, on the basis of the certain tunnel structure parameters. The conclusions are as follows: (1) The soil far away from the ground fissure is excavated by the method of up and down the steps to keep the core soil, the settlement of tunnel vault and surface are not affected by ground fissure. The settlement quantity in crack zone is obviously larger than the settlement quantity away from the crack zone that is excavated by up and down the steps to keep the core soil. During the crossing process by CRD, the settlement of the surface near the ground fissure excavated is affected by water seriously. Therefore, the measures of waterproofing and water draining should be prepared in the process of construction and avoid crossing the ground fissure in the rainy day. (2)The final convergence quantity and convergence rate of tunnel twist in the crack zone are much larger than the final convergence quantity and convergence rate away from the ground fissure. All the final convergence quantity can satisfy the requirement of safety. When switch the method of up and down the steps to keep the core soil to CRD, the deformation of tunnel twist is not affected by ground fissure. (3)The stress of lining for the tunnel is not symmetrical by CRD, the stress of the vault near the ground fissure is larger than the stress of the vault away from the crack zone. (4) The soil near the ground fissure is excavated, the CRD method is adopted to move forward overall, 4 part local side of the pilot tunnel soil is excavated by using up and down the steps, the biggest settlement of the surface reduces for around 5 mm; At the same time, setting up seam lining structure, making the waterproof and drainage measures in ground fissure and using duplex pipe grouting consolidation measures can reduce the surface subsidence.