关键词: 航道工程；管涵；开挖卸荷；沉降变形；沉降差；变形控制

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