为探明盾构隧道施工过程中同步注浆浆液浮力引起的管片错台量变化规律，以某大直径盾构隧道工程为例，提出“从整体受力状态分析到局部变形计算”的管片环间错台量计算方法，并分别建立盾构隧道施工期纵向分析模型与管片环间错台量计算模型，对不同埋深、不同浆液凝固时间和不同掘进速度条件下施工期隧道结构纵向受力、管片环间错台量进行计算与对比分析。结果表明： 1）采用盾构隧道施工期纵向分析模型计算隧道纵向内力，后将纵向内力作为边界条件代入管片环间错台量计算模型中求解错台量的方法是合理可靠的； 2）管片环脱出盾尾后受注浆浆液浮力、水浮力等作用产生负弯矩并承受最大剪力，易发生错台变形； 3）管片环间错台规律为管片环脱出盾尾后首先向上错台，经过渡段后向下错台，最后进入平稳阶段； 4）浆液凝固时间将显著影响施工期管片错台的产生，缩短浆液凝固时间可以有效减小管片环间错台； 5）埋深增大时，由于盾构推力增加、上覆载荷增大及围岩性质变好，将减少管片环间错台的产生，因此，对于埋深较小的盾构隧道应更加注意错台现象的发生。

To determine the variation laws of segment dislocation caused by the buoyancy of synchronous grouting slurry during shield tunneling, a method for the calculation of segment dislocation is proposed, starting with an analysis of the integral forced status and ending with the calculation of local deformation, based on a largediameter shield tunnel project. Then, via numerical and comparative analysis, a longitudinal analysis model of the shield tunnel during the construction period and a threedimensional(3D) calculation model of segment dislocation are established to calculate segment dislocation under different cover depths, grout densities, and grout solidification times. The results indicate the following. (1) It is reasonable to use the longitudinal analysis model of the shield tunnel during construction to calculate the longitudinal structural inner forces and then substitute the force boundary conditions into the 3D segment dislocation calculation model to determine the amount of segment dislocation. (2) As the segment ring exits the shield tail, it is subjected to the buoyancy of the grouting liquid and the buoyancy of the surrounding water, resulting in negative bending and maximum shear strain, which is prone to ring dislocation. (3) The segment dislocation laws are as follows: it begins with an upward stagger, followed by a downward stagger after passing through stable segments, and it eventually enters the stable stage. (4) The slurry′s qualities have a considerable impact on the occurrence of dislocation during tunnel construction. Dislocation between rings can be effectively decreased by lowering the density of the slurry and increasing the rate of solidification. (5) As the tunnel cover depth increases, segmental ring dislocation is reduced due to the increase in the overlying stress and the improved surrounding rock properties. As a result, greater attention should be paid to the occurrence of segment dislocation in shield tunnels with a shallow cover depth.