天津滨海Z2号线盾构隧道接头螺栓比选及抗弯刚度研究

Selection of bolted joints and bending stiffness of shield tunnel of Z2 metro line in Tianjin Binhai New Area

针对不同形式螺栓接头,充分考虑复杂接缝间的不连续性及接头预紧力,以天津滨海Z2号线盾构隧道管片纵缝为研究对象,分析比较了直螺栓、斜螺栓和弯螺栓三种接头在不同弯矩和轴力条件下对管片接缝力学性能的影响。根据分析结果给出了三种螺栓接头的适用性,以及三种螺栓接头在不同埋深、弯矩作用下的抗弯刚度建议值。研究结果表明:螺栓形式对螺栓最大受力位置影响很小;螺栓拉应力和接缝张开量随轴力的增大而减小,但接头抗弯刚度均随之增大;螺栓拉应力、接缝错台量和张开量随弯矩的提升而增大,但接头抗弯刚度随之减小。

Aiming at different types of bolted joints,taking into account the discontinuity of complex joints and the pre-tightening force of joints,the longitudinal joints of shield tunnel segments of Z2 metro line in Tianjin Binhai New Area are studied.The effects of straight bolts,oblique bolts and bending bolts on the mechanical properties of segment joints under different bending moments and axial forces are analyzed and compared.According to the analysis results,the applicability of the proposed three kinds of bolted joints and their values of bending stiffness under different buried depths and bending moments are given.The results show that the bolt form has little effect on the maximum stress position of the bolts.The tensile stress and joint opening of the bolts decrease with the increase of axial forces,but the bending stiffness of the joints increase.The tensile stress,dislocation and opening of the joints increase with the increase of the bending moment,but the bending stiffness of the joints decreases accordingly.