UNDER WATER PIPELINE EXCAVATION

摘要

The invention is concerned with a process for bringing a body of water into communication with a tunnel extending under the bed of the body of water. A cavity is excavated under the end of the tunnel adjacent the body of water, to a depth such that the volume of the cavity is at least equal to the volume of the ground forming the roof of the cavity and between the cavity and the bed of the body of water. The roof of the cavity is then collapsed and is received in the cavity. The invention is particularly useful in the connection of a pipe placed in the tunnel to an installation or pipe which is eventually immersed. For example a pipe may be provided on the bed of the body of water to be connected to a pipe in the tunnel, the connection being made after the cavity roof has been collapsed by introducing a pipe portion between the ends of the immersed and underground pipes.