考虑建筑刚度的盾构施工引致沉降计算方法

Calculation Method for Settlement due to Shield Tunnelling Considering Structure Stiffness

地表有建筑物存在时,地铁盾构隧道穿越建筑物施工引起的地表沉降槽形式受地表建筑物刚度的影响,与无地表建筑物存在时的情况有所不同。Verruijt和Booker曾对Sagaseta镜像法推广后提出了考虑半无限空间内岩土材料体积可变条件下适用于任意泊松比材料的浅埋圆洞位移及应力分布规律的近似解析解。基于该解析解并结合等效刚度原理,给出了考虑建筑物刚度时单线及双线盾构隧道穿越建筑物引起的地表沉降计算公式。结合上海轨道交通11号线穿越徐汇中学崇思楼工程,运用双线盾构隧道穿越建筑物引起的地表沉降计算公式对既有建筑物沉降进行预测,与监测结果对比显示吻合较好,验证了该公式的适用性。

For tunnel crossing under through existing buildings,the shape of surface settlement trough due to shield tunnelling is different from that under situation without buildings on the ground.Based on the stiffness equivalent method and the approximate solution of surface settlement proposed by Verruijt and Booker,which is an extension of the method suggested by Sagaseta,a new approximate solution is proposed in this article to calculate the surface settlement due to shield tunnelling considering the stiffness of structure.Combined with the Shanghai Metro Line 11 project crossing through the Chongsi Building in Xuhui Middle School,a calculation was carried out and the result was compared with the monitoring data,the comparison showed that the result of the approximate solution is acceptable.