沈埋トンネル施工時のトレンチ埋戻り特性に関する検討

抄録

The Immersed Tube Tunnel beneath the Bosphorus Strait is under construction in Istanbul, Turkey. When the tunnel element is immersed and set to the bottom in the trench, the sedimentation might be accelerated due to the converged current between the immersed tunnel element and the bottom. It affects the safety and the accuracy for the tunnel immersion work, significantly. In this study, the flow distributions around the tunnel element and the trench were obtained by the hydraulic physical model test at first. Then, the flow distribution and the sedimentation in the trench were calculated for the tunnel immersion work by using a numerical model. It is shown that the numerical model is capable of studying on the sedimentation for the tunnel immersion work. It is also confirmed that the immersed tunnel element is set to the bottom without the significant sedimentation in the case of the immersion work for the Bosphorus Tube Tunnel.