盾构隧道纵缝接头极限状态试验研究

Experimental Study on Serviceability Limit State and Ultimate Limit State of Concrete Segmental Lining Longitudinal Joints

摘要:

纵缝接头对盾构隧道衬砌结构的变形和内力起控制作用，且不同受力状态下的盾构隧道接头的力学性能差异较大。基于1:1的纵缝接头正、负弯矩荷载试验，通过加载接头至极限破坏，获得了纵缝接头在轴力和弯矩共同作用下的接缝张开、接头挠度、螺栓和管片混凝土的应变。根据连接螺栓、密封垫和管片混凝土的工作状态，确定了纵缝接头的使用状态极限；根据接头最终破坏的变形和承载状态，确定了纵缝接头的承载能力极限。最后，在对比试验结果与设计结果的基础上，研究了现行安全系数设计方法的安全储备。

关键词:盾构隧道;纵缝接头;原型试验;正常使用极限状态;承载能力极限状态

Abstract:

A series of full-scale tests on longitudinal joints subjected to positive and negative moments were conducted. The joints were continuously loaded until completely damaged, and the development of joint opening, joint deflection, bolt strain and concrete strain with the bending moment were obtained. Based on the deformation and stress state of bolt, gasket and segment stress, the serviceability limit state of longitudinal joints were derived. The ultimate limit state of longitudinal joints was determined according to the ultimate bearing capacity of the joints. Finally, based on the comparison between the test results and the design results, the safety reserve of current safety factor design method was researched.

Key words:shield tunnel;longitudinal joint;full scale tests;serviceability limit state;ultimate limit state