邻近建筑物进行基坑开挖会使桩基产生附加变形和内力，降低其承载能力，如果桩基变形过大会威胁到上部结构的安全。针对该领域目前存在的三维有限元数值模拟法建模复杂且计算耗时的现状，同时为了充分利用基坑围护位移较易通过现场监测技术获取的优势，提出了基于影像源法的基坑开挖引起邻近单桩变形影响的两阶段简化分析方法。同时，引入了Kerr地基模型，并针对Winkler地基模型进行改进，弥补了Winkler地基不能考虑土体连续性的缺陷。在第1阶段基于影像源法，由基坑围护变形计算基坑开挖引起的土体水平自由场位移；第2阶段分别基于Winkler和Kerr地基模型，将土体自由场位移施加于桩基，建立桩基在被动位移扰动下的微分控制方程，得到基坑开挖对邻近桩基影响的简化解析解，包括基坑开挖引起桩基的水平位移、弯矩和剪力等。将计算结果与既有理论结果、监测数据以及三维有限元数值模拟结果进行对比，取得了较好的一致性，其中基于Kerr地基模型的简化解比基于Winkler地基模型的简化解更为精确。该简化方法可为有效分析基坑开挖对邻近桩基的变形影响提供一定理论依据。

Foundation pit excavation can produce additional deformation and internal forces on the adjacent piles of buildings, and it will reduce their bearing capacity. This will threaten the security of the upper structure if the deformation of piles is too large. To avoid the drawbacks of three-dimensional numerical analysis, such as complexity modeling and time consuming, and to take full use of foundation pit supporting displacements provided by the in-situ monitoring technique, a two-stage method based on virtual image technique is presented for determining the behavior of adjacent single-pile induced by foundation pit excavation. An improved calculation model, Kerr foundation model, is proposed, which makes up for the defects that Winkler foundation model cannot consider the continuity of soil. The virtual image technique is used to estimate the free-field soil displacements induced by excavation in the first stage. The foundation pit supporting displacements are employed to calculate the free-field soil displacements. In the second stage, the free-field soil displacements are applied to the piles, the displacement governing equations of piles are established based on Winkler and Kerr foundation models, respectively. The simplified formula for pile response induced by excavation is obtained, including horizontal displacements, bending moments, and shearing force. The results are compared with that from existing calculated results, measured data, and 3D FEM. Good agreements are obtained. The simplified solution based on the Kerr foundation model is more accurate than the solution of Winkler foundation model. It indicates that the simplified calculation method can provide a theoretical base to analyze the impacts of excavation on the adjacent piles effectively.