基坑开挖变形及其对周围建筑的影响分析

Excavation Deformation Analysis of Foundation Pits and Its Influence on Surrounding Buildings

随着城市空间的高效利用,新建基坑工程施工难度越来越大,基坑开挖变形及其对周边既有建筑影响的研究愈加重要。以某深基坑工程为例,利用三维有限元模型对基坑实际开挖过程进行数值模拟计算,结合实测变形数据对基坑变形特征及其对周围建筑物的影响进行综合分析。结果表明:新基坑开挖过程中,围护结构发生了整体偏向基坑内部的侧向位移,最大位移发生在基坑围护桩紧邻建筑物一侧的中部;基坑周边及底部土体沉降呈“凹槽型”,即开挖深度越大,沉降越大;新基坑开挖导致周围建筑物产生了不同均匀沉降,但随着围护结构的施工,建筑物变形逐渐减小并趋于稳定。研究结果可为类似深基坑工程设计和施工提供一定的参考。

With the efficient use of urban space, the construction of new foundation pit projects is becoming more and more difficult, and the research on the excavation deformation of foundation pits and its impact on surrounding buildings is becoming more important.Taking a deep foundation pit project as an example, this study uses a three-dimensional finite element model to numerically simulate the actual excavation process.Moreover, the deformation characteristic of foundation pits and its influence on the surrounding buildings are comprehensively analyzed with the measured deformation data.The results reveal that during the excavation of a new foundation pit, the overall lateral displacement of the retaining structure toward the inside of the foundation pit occurs, and the maximum displacement occurs in the middle of the foundation pit retaining piles adjacent to the side of the buildings.The settlement of soil around and at the bottom of the foundation pit is “groove-shaped”,namely that when the excavation goes deeper, the settlement is greater.The excavation of the new foundation pit leads to the different uniform settlement of surrounding buildings, but with the construction of the retaining structure, the deformation of buildings decreases gradually and tends to be stable.The research results can provide some theoretical reference for the design and construction of similar deep foundation pit projects.