盾构隧道管片衬砌壳弹簧计算模型研究

Shell-spring Calculation Model for Segment Lining of Shield Tunnels

针对现有盾构隧道管片衬砌计算模型存在的问题,对管片接头的力学特性进行了分析。认为管片的接头实际应包括管片接缝和对应手孔间的管片部分,采用点弹簧模拟管片接头力学特性实际上是夸大了端部管片的刚度。提出了基于壳弹簧模式的管片结构的整体环纵向非连续计算模型,改进了接头的模拟方法。该模型将管片接缝以及对应手孔间管片部分视为一个受力整体,其宽度约为对应手孔之间的弧长,并提出了该接头抗弯刚度的定义方式。由于该模型考虑了管片接头的整体性,计算得到的内力值比梁弹簧模型计算结果更加准确,且可反映管片结构纵向的受力特征。

Regarding the existing problem of shield tunnel segments calculation model,this paper analyzed the mechanical properties of the segment joint. It was considered that the joint of the segment should include the joint and the segment part between the two connected hand holes. Adopting the point spring to simulate the mechanical property of the joint actually exaggerated the rigidity of the end parts of segments. The closed ring calculation model based on the shell-spring mode was proposed,which improved the simulation method of the segment joint. In the model,the joints and some parts of segments between the two connected hand holes is regarded as a whole structure,the width of which is approximately the arc length between the connected hand holes,and the method of defining the flexural rigidity of this joint model was proposed. With this model,the internal force values were more precise than the results of beam-spring model because of considering the integrity of annular segment joint,and this model could show the longitudinal mechanical properties of the segments.