盾构隧道侧穿筏板基础变形响应与安全评估

Deformation Response and Safety Evaluation of Side-Crossing Raft Slab Foundation in Shield Tunnel Construction

随着城市地铁进入大规模建设阶段,地铁隧道将侧穿众多基础形式不同的既有建筑物,为了确保建筑物的安全使用及地铁的正常施工,需要在地铁隧道穿越建筑物地基基础施工前对其进行安全性评估。本文结合北京地铁十号线二期盾构隧道侧穿某筏板基础建筑物的工程实例,通过对建筑物现状调查与检测,对建筑物结构体系、倾斜及沉降现状进行评价;利用FLAC3D软件进行数值计算,研究盾构到达建筑物前、通过及离开建筑物三个阶段的地表横向及纵向变形规律;最后综合建筑物地基基础已发生变形和盾构施工将产生的基础附加变形,依据规范提出该建筑物地基基础变形控制标准,据此来指导盾构隧道安全施工。

The metro construction in cities has been in a on phase. The metro tunnel will side cross many finished buildings in different foundation forms. In order to guarantee the safe use of buildings and the normal construction of the subway, safety evaluation is needed before the foundation construction of subway tunnel side-crossing the buildings. In this paper, Beijing Subway Line 10 is used as the engineering example. The construc- tion system, inclination and variation of the buildings are evaluated through the examination of the buildings. FLAC software is used to do the calculation in order to study the variation characteristics of the buildings in different con- struction stages. Then based on building foundation deformation and additional deformation caused by shield construc- tion the deformation control standard is raised to provide guidance for the construction of shield tunnel.