Static and Dynamic Experimental Analysis of An Immersion Joint

As the weakest part of an immersed tunnel, the immersion joint is the key element in research in this field. Relatively large deformations and internal forces may be induced in the immersion joint subjected to various loading types. Based on a real project, the shear mechanical behaviour is investigated by large scale model test. To explore the performance of the immersion joint, compression-shear loads are applied on a tunnel segment in a specific test set-up. For the applied loading schemes, different levels of axial force, corresponding to the water depth of the joint, are considered as well as varying amplitudes of the shear force. Based on these results, both the static and dynamic shear stiffness of an immersion joint were analysed. The results of the test indicate that the static shear stiffness of the joint increases linearly with the axial force and the same trend is found for the dynamic one. Moreover, the dynamic stiffness is larger than the static one.