Abstract: The intersecting of the culvert and the approach channel of the lock in coastal area is easy to cause the uneven settlement, structural cracking and water stop failure of the culvert, which will affect the stability of the culvert structure. Aiming at the deformation and control problem of overburden culvert structure under approach channel, a simulation model of the whole construction process of the culvert was established by using the numerical simulation method. Combined with the field measured data, the settlement law and deformation control effect of the culvert under different construction loads and foundation reinforcement schemes were analyzed. The research results show that the small strain plastic hardening model can be used to simulate the whole process of pipe culvert construction in coastal area. In the case study, the average settlement of the pipe culvert exceeds the allowable value due to the uneven load on the pipe culvert. The foundation treatment scheme of the culvert with bored cast-in-place pile is proposed to enhance the foundation stiffness and effectively reduce the settlement of the culvert. Uneven settlement will still occur in the box where the foundation treatment is different, resulting in differential settlement between the structural joints of the box. Affected by the excavation and unloading of the approach channel, the pipe culvert under the approach channel has an upward displacement, which reduces the uneven settlement of the box and the settlement difference at the structural joints, and is conducive to the stability of the pipe culvert. The proposed deformation control scheme of pipe culvert meets the engineering requirements.

Key words: waterway engineering; pipe culvert; excavation unloading; settlement deformation; differential settlement; deformation control

摘要： 滨海地区管涵与船闸引航道交叉，容易引起管涵的不均匀沉降、结构开裂、止水失效，会影响到管涵结构的稳定性。针对引航道下覆管涵结构的变形及控制问题，采用数值模拟方法建立管涵施工全过程仿真模型，结合现场实测数据，分析了不同施工荷载、地基加固方案下管涵沉降规律和变形控制效果。研究结果表明：小应变塑性硬化模型可用于滨海地区管涵施工全过程仿真模拟；算例管涵受上覆不均匀荷载作用，导致管涵的平均沉降超过允许值，采用的钻孔灌注桩管涵地基处理方案，增强了地基刚度可有效减小管涵的沉降；地基处理差异处箱体仍会出现不均匀沉降，造成箱体结构缝之间出现沉降差；受引航道开挖卸荷的影响，引航道下覆管涵产生向上位移，减小了箱体的不均匀沉降和结构缝处的沉降差，有利于管涵的稳定性，提出的管涵变形控制方案满足工程要求。

关键词: 航道工程；管涵；开挖卸荷；沉降变形；沉降差；变形控制