地铁隧道盾构施工侧穿建筑物独立基础的动态响应分析

隧道施工引起隧道周围地表发生变形并可能危及周围地面建筑设施安全,因此,施工前需要了解隧道施工对周围建筑物的影响。本文以北京地铁10号线2期盾构隧道穿越某大厦为典型实例,用FLAC3D 程序进行了数值模拟研究。首先根据测量的数据对建筑物的现状进行了分析,研究了由于盾构施工所引起的土体位移场的变化趋势,模拟了在盾构隧道开挖的不同阶段,建筑物基础的动态响应,预测了独立基础的不均匀沉降。并且对在建筑物与隧道间施打隔离桩加固的施工方案进行了分析,提出了盾构隧道穿越独立基础建筑物的安全评价方法。当考虑盾构隧道施工对建筑物地基基础影响的问题时,应综合考虑建筑物地基基础现有的变形和由于盾构施工诱发的基础附加变形,在两者的共同作用下,保证基础的变形在规范规定的限值以内,才能保证建筑物在隧道施工的过程以及使用过程中的正常使用。为日后有关盾构隧道穿越建筑物问题提供了参考。

THE DYNAMIC RESPONSE ANALYSIS OF INDEPENDENT FOUNDATIONS ON UNDERGROUND SHIELD TUNNEL CONSTRUCTION OF ADJACENT BUIDINGS

Tunnel construction may lead to ground deformation.So,in the preparation phase,its necessary to analysis the impact of the construction to surrounding buildings.This article taking shield tunnel construction crossing A Building for Beijing metro line 10 phase 2 as an example,conducted a numerical simulation research by FLAC3D.First,the building status is analyzed by measurement date,then,this article analyzed effects of ground settlement caused by shield tunnel construction on the buildings independent foundation based on numerical simulation,and it has predicted the trend of changes in soil-displacement-field and uneven settlement of the independent foundation,simulated the excavation of shield tunnel in different stages,and the dynamic response to the building foundation,forecasting the uneven settlement of foundation independence.This article analysis the construction scheme about isolation piles driving,and proposes an evaluation methodology that can be used by shield tunnel construction crossing independent foundation,when considering the influence of tunnel construction to structure foundation,Should considering the existing deformation and additional deformation caused by tunnel construction.In order to ensure the normal use of building,building deformation must be controlled in standard,in addition,this article can give references to the same kind of shield tunneling in the future.