marine soil
3.In this paper, the marine route survey factors, such as water depth, bottom slope, soil shearing strength, tidal current and thunderstorm and their roles in the submarine fibreoptic cable engineering are introduced, and their roles and necessities in the cable construction are also appraised, which will make the combination of marine route survey with construction demand closer and the marine route survey be aimed at the cable engineering practice.
5.In view of the technical problems of softening of foundation Soil and reduction of bearing capacity of the breakwater under the action of repeated wave loads during the execution of the second phase of the deepwater waterway regulation project in the Changjiang Estuary, Tianjin Port Construction Corporation has successfully developed safer, higher quality and highly efficient technology and special-purpose marine craft and machinery for laying deepwater sand blankets and offshore installation of prefabricated drains, which were more suitable for the working conditions in the Changjiang Estuary, and has also explored the construction technology for prefabrication of caissons with rubber anti-sliding plates, to ensure the efficient implementation of the engineering measures against softening of foundation soil.
6.The bottom topography and geomorphology in the area are complex,and there are many geologic hazard factors including submarine deep scour channel,buried ancient river course,shallow gas formation,tidal sand ridge and creek,buried ancient steep slope and possible soil liquefaction,which will constitute direct or potential hazards to the marine structures,so attention should be paid to these geologic hazard factors.
