考虑开挖后的洞周应力释放效应,采用有限元方法,使用厚壳、剪切弹簧、转动弹簧、压缩弹簧、接触及空间实体多种单元分析盾构隧道管片衬砌的三维内力状态,提出了地层-结构模式下的壳-弹簧-接触计算模型。该模型较好地考虑了管片间接缝处的挤压作用、管片接头刚度的影响、管片与围岩的共同变形以及封项块的近似插入角,因此能有效地模拟盾构隧道管片衬砌的复杂受力状态。
Considering the stress release around excavation, the shell-spring-contact calculation model of stratum-structure mode is presented so as to analyze the 3D member forces of the segmental linings of shield tunnel. With the application of FEM, the model employs several types of elements, such as thick shell, shear spring, rotational spring, compression spring, contact and solid elements, and concerns with the extrusion between segments in the joints, the stiffness contribution of joints, the cooperation between segments and surrounding rock, and the approximate insertion angle of Key Segment. Consequently, the complex mechanical behavior of the segmental linings can be effectively simulated by applying the model.