An Experimental Study on Bending Behavior of Composite Hollow RC in Submerged Floating Tunnel (SFT)

Abstract

In case of a submerged floating tunnel (SFT), which has difficult to cast in-site underwater construction, it is considered to be the most reasonable construction method using the module fabrication which move it from the coast to the field site using the ship. So, it is essential to investigate the structural performance of the joints between the modules. A concept of the steel composite hollow in SFT maintaining stably the joints has been proposed by applying prestressing method to resist various external loads. In this study, the bending behavior of module joints in a steel composite hollow tunnel was experimentally analyzed to evaluate the safety for the bending deformation which is dominant in SFT. In consequence of test, there is a performance difference at the module joint depending on whether or not the connection of the inner steel tube. The bending stiffness of the module joints in SFT was very similar but there was a difference in strength. The safety criteria for evaluating the bending behavior of the modular joint depends on the application of the tunnel. As a result, to design the module joint according to the application of SFT, it is possible to consider both methods which is allowing the ductility behavior of internal tube and controlling the tight connection. And, the failure criterion of the bending behavior of the module joint can be selected as the maximum load or deformation limit. site using the ship. So, it is essential to investigate the structural performance of the joints between the modules. A concept of the steel composite hollow in SFT maintaining stably the joints has been proposed by applying prestressing method to resist various external loads. In this study, the bending behavior of module joints in a steel composite hollow tunnel was experimentally analyzed to evaluate the safety for the bending deformation which is dominant in SFT. In consequence of test, there is a performance difference at the module joint depending on whether or not the connection of the inner steel tube. The bending stiffness of the module joints in SFT was very similar but there was a difference in strength. The safety criteria for evaluating the bending behavior of the modular joint depends on the application of the tunnel. As a result, to design the module joint according to the application of SFT, it is possible to consider both methods which is allowing the ductility behavior of internal tube and controlling the tight connection. And, the failure criterion of the bending behavior of the module joint can be selected as the maximum load or deformation limit.