Abstract As a bridge envisaged in the future of tunnel crossings, the submerged floating tube bridge (SFTB) is a floating bridge, submerged at a defined position under the water level. The closed cross-section resembles that of a tunnel, but the design of the SFTB is governed by the dynamic behaviour of the structure, as for a bridge. Even though the concept was first proposed at the end of the nineteenth century, it is only in recent years, with the studies for the E39 fjord crossing project in Norway, that the real feasibility of the structure has been proven. In an era of a lack of available land to accommodate population growth, this structure offers the advantages of tunnels in using the underground space to hide the transport system, optimizing the use of the land. Several aspects have to be considered in the design to make this new concept a technologically competitive reality for transport systems. Most importantly, continuous research and development will be the key to successful realization of the concept in the near future.

中文翻译：

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隧道穿越的未来：水下浮管桥

摘要 作为未来隧道穿越中设想的桥梁，潜管浮桥（SFTB）是一种浮桥，淹没在水位以下的特定位置。封闭的横截面类似于隧道的横截面，但 SFTB 的设计取决于结构的动态行为，就像桥梁一样。尽管这个概念是在 19 世纪末首次提出的，但直到最近几年，随着对挪威 E39 峡湾穿越项目的研究，该结构的真正可行性才被证明。在缺乏可用土地来适应人口增长的时代，这种结构在利用地下空间隐藏交通系统方面提供了隧道的优势，优化了土地的使用。在设计中必须考虑几个方面，以使这个新概念成为交通系统的技术竞争现实。最重要的是，持续的研发将是在不久的将来成功实现这一概念的关键。