Solution to the traffic problems of long and deep water straits–smart submerged floating tunnel and its research

Submerged floating tunnel (SFT) is a new type of structure across long and deep water straits and waterways with good application prospects. The structure is different from the traditional large-span bridges and immersed tunnels, which can effectively avoid difficulty under the construction of bridges foundation in deep water straits and channel, the high cost of large span bridge, influence of typhoons and heavy fog et al. severe weather on the vehicle driving on the bridges, a series of technical problems confronted under the construction of immersed tunnel or tunnel excavation in complex marine geology and the deep sea and risk control and so on. This paper, in the light of the characteristics of submerged floating tunnels and the requirements of marine deep water environment, discusses some of technical challenges faced in the designing and building the SFT, points out that it is necessary to systematically study the design and load condition, the smart composite material and shape optimization, the calculation theory and method for analyzing the structural behavior, the structure safety evaluation, construction methods and key technology, and engineering risk analysis, smart monitoring, evaluation and control, code or guide for design and construction of SFT. It lays foundation for design, construction and engineering risk analysis, etc. of submerged floating tunnel across the long and deep waterways in the future.