Joints are the weakest parts of prefabricated tunnels, and it is important to consider the material nonlinearities, mechanical properties and complex behaviours of joints in structural design. Based on existing joints, this paper proposes the design of three new types of joints for fabricated rectangular tunnels, including self-weight mortise and tenon joints, bolt mortise and tenon joints and steel plate mortise and tenon joints. To explore the mechanical behaviour and damage characteristics of these new joints, three-dimensional finite element numerical models are established with a plastic damage model to reflect the nonlinear mechanical characteristics of each component of the joint. The results of the numerical analysis are compared with experimental data, verifying the validity of the process. Then, the compressive and bending capacity, steel reinforcement bar stress and concrete damage characteristics of rectangular tunnel joints under different combinations of axial loads and displacement loads are defined. It is indicated that the mortise and tenon joint type significantly affects the damage evolution process of the concrete at these joints. Among the three joint types, the bolt mortise and tenon joint has the largest damage area of concrete and, consequently, the most damage elements due to its reasonable joint structure. Hence, from the perspective of the mechanical performance of the structure, the bolt mortise and tenon joint provides the largest flexural bearing capacity and structural safety, followed by the steel plate mortise and tenon joint. The self-weight mortise and tenon joint has the smallest flexural bearing capacity, but it is the simplest joint proposed and is easier to construct than the other two joints.

节点是预制隧道中最薄弱的部分，在结构设计中考虑节点的材料非线性、力学性能和复杂行为是很重要的。本文在现有节点的基础上，提出了三种新型装配式矩形隧道节点的设计方案，包括自重式榫卯节点、螺栓式榫卯节点和钢板榫卯节点。为了探索这些新型接头的力学行为和损伤特性，建立了三维有限元数值模型和塑性损伤模型，以反映接头各部件的非线性力学特性。数值分析的结果与实验数据进行了比较，验证了该过程的有效性。然后，压缩和弯曲能力，定义了不同轴向荷载和位移荷载组合下矩形隧道节点钢筋应力和混凝土破坏特性。结果表明，榫卯节点类型对这些节点处混凝土的损伤演化过程有显着影响。在三种接头类型中，螺栓榫卯接头由于其合理的接头结构，对混凝土的破坏面积最大，因此也是破坏元素最多的一种。因此，从结构的力学性能来看，螺栓榫接提供了最大的抗弯承载力和结构安全性，其次是钢板榫接。自重式榫卯连接具有最小的抗弯承载力，