大断面宽幅盾构管片三维内力分布分析

以武汉长江隧道工程为例，采用三维壳-弹簧计算模型，对不同幅宽和不同环间接头剪切刚度的管片衬砌结构力学分布进行了分析，并与梁-弹簧模型结果在量值上做了全面比较。研究表明，全环最大弯矩发生在幅宽边缘部位；环间接头剪力对幅宽边缘影响较大，而对幅宽中央影响偏小；当环间接头剪切刚度为非无穷大时，壳模型的幅宽边缘最大弯矩值略微大于梁弹簧模型相应结果，而当无穷大时两者数值则基本相等；壳模型的幅宽中央的最大弯矩值介于梁模型错缝与通缝拼装的数值之间，并随幅宽加大而趋于接近通缝拼装的结果；大幅宽条件下，不宜将梁-弹簧模型的环间最大剪力结果作为环间接头抗剪设计的计算依据。

Analysis of 3D internal forces distribution of wide segment lining for large-section shield tunnel

Taking the Wuhan Yangtze River tunnel as an engineering background, the internal forces distribution of segment lining structure with different segment widths and different ring joint shear stiffnesses is analyzed by 3Dshell-spring model and compared with the results achieved by beam-spring model. The study shows that: the maximum bending moment on the entire ring always occur on the edge of segment; the ring joint shear force has an great impact on the edge of segment and less in the middle of segment; when the ring joint shear stiffness is non-infinite, the maximum bending moment on the edge of segment calculated by shell-spring model is slightly larger than the results by beam-spring model; and these results almost equal when the joint shear stiffness is infinite; the maximum bending moment in the middle of segment calculated by shell-spring model is between the results by beam-spring model with stagger-jointed and those results by beam-spring model in sequence, and tend to the results in sequence with the segment width increased; when the segment width is large, the maximum shear force between rings calculated by beam-spring model is unfit for shear design of the ring joint.