关键词: 管片接头, 半刚性连接, 转动刚度, 衰减速度, 类指数函数

Abstract: The stiffness of segment joint is an important parameter for the design of shield tunnel linings. While, in stuctural calculation, estimation the bending stiffness of segment joint usually rely on empirical formula or full-scale tests. In order to evaluate bending stiffness of segment joint more conveniently and accurately, the authors try to establish an analytical model of segment joint, which providing theoretial foundation for determining the bending stiffness in structural calculation. In this paper, according to the structural features of segment joints, the authors mainly discuss the mechanical behavior of bolted segment joints considering them as semi-rigid, and then the moment-rotation behavior of the joint is studied. A physically based mathematical model using the joint dimensions and material properties is proposed. Considering joints connected by two long curved bolts as examples, parameters in the model are evaluated, and moment-rotation curves for the joint are presented. The model distinguishes joint’s mechanical behavior before and after joint opening, and agrees well with real mechanical behavior of the joints. Comparison with previous tests of segment joint and other models (such as Janssen model and Gladwell model) is conducted. The model proposed is more accurate and universal. Joint opening angles, decay of bending stiffness and tolerance bending moment are playing dominent roles in the exponential-like model. The model can provide a theoretical method to determine key parameter, bending stiffness, of structural calculation in segment lining design.

Key words: segment joint, semi-rigid connection, bending stiffness, rate of decay, exponential-like function