中文摘要：

接头是沉管隧道中最薄弱并且非常关键的部位,其力学性能直接影响整条沉管隧道的安全性与水密性。目前研究仅限于沉管接头的压缩、压弯和压剪等简单荷载工况,未对组合工况如压-扭-剪工况进行过研究。以红谷隧道工程为背景,基于三维精细化建模技术,通过有限元软件ABAQUS建立了表征沉管隧道接头性能的力学模型,并考虑不同材料的非线性本构模型,开展了沉管隧道接头在压-扭-剪组合条件下的力学性能模拟研究,并与压-剪组合条件下的力学性能进行对比了分析。通过数值模拟计算揭示了沉管接头GINA橡胶止水带超弹性材料的特性及水密性,并得到了接头在压-扭-剪组合条件下的水平荷载-位移曲线,从而获得了接头的扭剪刚度和极限承载力,表明接头在压-扭-剪工况下的抗剪强度比压-剪工况下的抗剪强度小。同时,对混凝土及钢剪力键进行局部分析,得到其在压-扭-剪组合条件下的受力特性,并预测了剪力键可能的破坏模式。研究结果可为今后沉管隧道接头设计提供参考。

英文摘要：

The joint of immersed tunnel is the weakest and important part, of which the mechanical performances directly affect the safety and water tightness of the whole immersed tunnel. However, there is no related study of construction condition under compression-torsion-shear combined loads. A mechanical model of joint of Honggu Immersed Tunnel is established by ABAQUS software based on 3D refined modeling technology. The mechanical performances of immersed tunnel joint under compression-torsion-shear combined loads are simulated considering nonlinear constitutive model and compared with those under compression-shear combined loads. The hyperelastic material characteristics and tightness of GINA rubber water stop tie for immersed tunnel joint are revealed by numerical simulation calculation. The horizontal load-displacement curve of joint under compression-torsion-shear combined loads is obtained; and the torsion-shear stiffness and ultimate bearing capacity of joint are obtained consequently; it is shown that the shear strength of joint under compression-torsion-shear combined loads is smaller than that under compression- shear combined loads. Meanwhile, the mechanical performances of concrete and steel shear keys under compression- torsion-shear combined loads are obtained by local analysis. The potential destruction modes of the shear keys are predicted. The study resuhs can provide reference for design of immersed tunnel joints of similar projects in the future.