Underwater tunnel units for temporary water crossing

摘要

The temporary water crossing tunnel uses prefab. tunnel sections interconnected on site. At least one part of each tunnel section is made of steel, concrete, or a composition which can float in water. Each part is used as a ferry and subsequently sunk and water-tightly interconnected. The tunnel sections are of jacketed type. They may be loadable and unloadable at both ends. Alternatively they may be of a double type and chamfered at the lateral bottom section, with ends containing protrusions to assist in assembly.