Flexural behavior of segmental joints plays a crucial role in the design of lining structure of shield tunnels, and many novel joints are proposed to enhance its flexural behavior. This paper presents a comprehensive investigation of the flexural behavior of a new segmental joint containing double rows of bolts, proposed for a deep-buried shield tunnel in Shanghai, via the full-scale experimental tests and refined numerical simulation. Both the positive and negative moment loading scenarios are considered. The flexural behavior of segmental joints containing double rows of bolts shows obvious nonlinear characteristics and the moment-rotational angle curve can be divided into three stages: linear growth stage, plastic development stage and ultimate failure stage. Thus, a tri-fold line stiffness model is proposed to describe the nonlinearity of joint stiffness, which can be easily implemented into the spring-beam model. Compared to the segmental joints using only single row of bolts, the joint containing double rows of bolts has a higher joint stiffness and bearing capacity. Meanwhile, the bending capacity of joints increases with the axial force. For the failure mode, the positive bending condition is characterized by the spalling of concrete in the compression zone and the fracture of joint panel; while the tensile failure of bolt is found under negative moment scenario. All these characteristics are obtained in the tests and well interpreted by the simulation.

分段节理的抗弯性能在盾构隧道衬砌结构设计中起着至关重要的作用，人们提出了许多新颖的节理来增强其挠曲性能。本文通过全面的试验测试和精细的数值模拟，对上海某深埋盾构隧道提出的包含双排螺栓的新型节段节点的抗弯性能进行了全面研究。同时考虑了正负荷载情况。含双排螺栓的节理接头的弯曲行为表现出明显的非线性特征，弯矩-转角曲线可分为三个阶段：线性增长阶段，塑性发展阶段和极限破坏阶段。因此，提出了一种三折线刚度模型来描述节点刚度的非线性，可以很容易地将其实现为弹簧梁模型。与仅使用单排螺栓的分段式接头相比，包含双排螺栓的节式接头具有更高的接头刚度和承载能力。同时，接头的抗弯能力随轴向力而增加。对于破坏模式，正弯曲条件的特征是压缩区混凝土剥落和接缝面板断裂。而在负弯矩情况下发现螺栓的拉伸破坏。所有这些特性都是在测试中获得的，并且可以通过仿真得到很好的解释。包含双排螺栓的接头具有更高的接头刚度和承载能力。同时，接头的抗弯能力随轴向力而增加。对于破坏模式，正弯曲条件的特征是压缩区混凝土剥落和接缝面板断裂。而在负弯矩情况下发现螺栓的拉伸破坏。所有这些特性都是在测试中获得的，并且可以通过仿真得到很好的解释。包含双排螺栓的接头具有更高的接头刚度和承载能力。同时，接头的抗弯能力随轴向力而增加。对于破坏模式，正弯曲条件的特征是压缩区混凝土剥落和接缝面板断裂。而在负弯矩情况下发现螺栓的拉伸破坏。所有这些特性都是在测试中获得的，并且可以通过仿真得到很好的解释。而在负弯矩情况下发现螺栓的拉伸破坏。所有这些特性都是在测试中获得的，并且可以通过仿真得到很好的解释。而在负弯矩情况下发现螺栓的拉伸破坏。所有这些特性都是在测试中获得的，并且可以通过仿真得到很好的解释。