V形超大直径盾构隧道在越江隧道中较为常见，有必要针对隧道施工过程中纵向坡度对管片上浮的影响展开研究。依托佛山市季华路西延线工程，建立粉砂地层考虑浆液时变特性的盾构隧道掘进数值分析模型，研究隧道纵向坡度对管片上浮的影响，通过改变推进系统荷载分布施加偏转力矩，分析不同坡度及覆土厚度下偏转力矩与管片上浮的关系。结果表明： 1）管片上浮量随掘进环数增加而增加，后面变形趋于平缓。2）在浅覆土条件下，隧道下坡段掘进时管片上浮量最大，水平段次之，上坡段最小；在较深覆土条件下，坡度对管片上浮的影响不大。3）在不同坡度下，正偏转力矩均对管片上浮起抑制作用，且在较深覆土条件下抑制效果较好。
V-shaped super-large diameter shield tunnel has been commonly adopted in cross-river projects. It is necessary to study the influence of
longitudinal slope on segment floating during tunnel construction. Based on the
west extension project of Jihua road in Foshan city, a numerical analysis model
of shield tunneling in silty sand strata considering time-varying characteristics of grout is established. The influence of
tunnel longitudinal slope on segments floating is studied. The deflection
moment is applied by changing the load distribution of propulsion system, and
the relationship between deflection moment and segments floating under
different slopes and burial depth is analyzed. The results show that: (1) The
floating of segments increases with the number of driving rings, and then tends
to be stable. (2) For shallow buried tunneling, the floating of segments is the
largest in the downslope section, larger in the horizontal section，and the smallest in the upslope section； for
deep buried tunneling, the slope has little effect on segment floating. (3) For
all longitudinal slopes, the positive deflection moment can inhibit the
floating of segment, and the inhibition effect is better for deep buried
tunneling.
