类矩形盾构隧道衬砌结构设计模型研究

为了得到适用于类矩形盾构隧道结构设计模型，通过整环足尺试验模拟类矩形盾构隧道在正常运营工况下的实际受力，得到试验结构的变形和内力，采用等效刚度模型和梁-弹簧模型对试验结果进行分析，得到有效的类矩形盾构隧道结构设计参数. 结果表明:采用等效刚度模型作为类矩形盾构隧道结构计算模型，难以得到同时符合结构长短轴变形的管片刚度折减系数；采用梁-弹簧模型作为类矩形盾构隧道结构计算模型，结构变形和结构内力计算结果和足尺试验结果较为匹配，能真实反应类矩形盾构隧道结构受力，选用梁-弹簧模型作为类矩形盾构隧道结构计算模型更为合理，所研究类矩形结构管片接缝的抗剪刚度建议为341 × 106～368 × 106 N/m；负弯矩接缝抗弯刚度建议为114 × 106～491 × 106 N?m/rad，正弯矩接缝抗弯刚度范围为85 × 106～177 × 106 N?m/rad. 

Study on Design Model of Quasi-Rectangular Shield Tunnel Linings

In order to obtain a design model for quasi-rectangular shield tunnel linings, a full-scale ring test was conducted to acquire the deformation and internal forces of the linings with loads simulated according to the actual ones in normal operation conditions. The test results were then analyzed in comparison with the numerical results based on the equivalent stiffness model and the beam-spring model, to determine parameters of the design model of quasi-rectangular tunnel linings. Results show that using the equivalent stiffness model to design of the quasi-rectangular shield tunnel linings, the segment stiffness reduction factor that can account for the deformation along both the long and short axes could not be obtained. While applying the beam-spring model, the computed structural responses and the influence of longitudinal joints on moment distribution both agree well with the experimental results. Therefore, it is more reasonable to use the beam-spring model as the design model of quasi-rectangular shield tunnel linings. For the quasi-rectangular shield tunnel linings under study, input parameters for the design model, including the shearing rigidity, negative-moment bending rigidity, and positive-moment bending rigidity of segment joints, are recommended as 341 × 106 ? 368 × 106 N/m, 114 × 106 ? 491 × 106 N?m/rad, and 85 × 106 ? 177 × 106 N?m/rad, respectively