盾构隧道施工对邻近桩基的影响研究

以杭州地铁隧道二号线某区间盾构下穿桩基建筑为研究对象，通过数值模拟方法分析了盾构隧道布置位置对邻近桩基变形的影响，并与土层变形传统预测公式进行比较。研究结果表明:当隧道位于桩基正下方时，隧道开挖造成上部桩基及周边土体较大沉降；随着隧道和桩基水平距离增加，隧道开挖对桩基和周边土体影响逐渐减小；当水平距离与桩径的比值（L/D）大于6时，隧道开挖对桩基及周边土体影响较小，数值模拟结果和传统公式预测值接近。

Study on Influence of Shield Tunnel Construction on Adjacent Pile Foundation

Taking the structure of shield tunnel under-crossing pile foundation in a section of Metro Line 2 in Hangzhou as the study object, the influence of the shield tunnels layout on the adjacent pile foundation is analyzed by numerical simulation, which is compared with the result of the traditional formula predicting soil deformation. The study result shows that where the tunnel locates directly under the pile foundation, the tunnel excavation causes large settlement of the above pile foundation and the surrounding soil mass; as the horizontal distance between the tunnel and the pile foundation increases, the tunnel excavations effect on the pile foundation and the surrounding soil mass decreases; when the ratio of the horizontal distance and pile distance is more than 6, the influence is minor; and the result of the numerical simulation is close to the predicated value obtained from the traditional formula.