城市地铁盾构隧道在从地面建筑物下穿越时，会对既有建筑物的安全稳定造成影响。如何合理控制由于隧道施工引起地面建筑物的倾斜、地基沉降，是地铁工程设计和施工时必须考虑的。以广州地铁五号线盾构区间建筑物桩基托换为例，详细讲述桩基托换设计、施工全过程，给类似工程的设计、施工提供参考。

The safety and stability of the existing buildings may be jeopardized when shieldbored tunnels stretch underground. During the design and construction of Metro works, efforts must be made so as to control the leaning of the buildings and the settlement of the ground caused by tunnel construction within the allowable values. Taking the pile foundation underpinning made during the construction of the shieldbored tunnel on line 5 of Guangzhou Metro as example, the authors present in detail the design and construction procedure of the underpinning, which can provide reference for the design and construction of similar works in the future.