Abstract: A method of constructing a column-like marine structure including the steps of constructing and placing an assembly of floats in a dry area, placing on the float assembly a column base having its own buoyancy, flooding the area to float the assembly of floats and column and moving them to deeper water, ballasting the floats to sink them and while maintaining buoyancy of the column removing the floats, completely ballasting the column to sink it, reconnecting the floats around the top of the column, constructing a further column part on top of the column, lifting the assembly by the buoyancy of the floats and/or the buoyancy of the column and floating it to a desired location in deeper water.

Abstract: A method is disclosed for manufacturing a double-walled hollow lost casing for use in the production of marine engineering civil works having inner and outer walls each made of pre-cut plates of such size and shape that the lost casing has a polygonal cross-section throughout its height. The method includes the steps of assembling a jig by interconnecting a plurality of standard frames stacked upon each other to a desired height which together present an outer surface generally corresponding to a wall of a lost casing to be produced, assembling on and releasably attaching the pre-cut plates to the outer surface of the jig and seamlessly joining the assembled plates, and then releasing the completed wall from the jig.

Abstract: Method and apparatus for lowering a heavy hollow column into hard soil and rock at the bottom of a body of water which column has a downwardly widening outer surface and a sharp lower edge. By means of plurality of suction nozzles erosive water flows are generated alongside and below the lower edge which sharp lower edge due to the erosive effect of the water flows and the local tensions generated in the soil by the weight of the column disintegrates the soil.

Abstract: The invention relates to a process and a floating apparatus (1, 2, 18) for the construction of columnlike elements (16, 17), forming part of a pier, a jetty or the like marine structure, in which a first part (16) is manufactured on a support (5) attached to the floating apparatus. Whilst said apparatus rests on the waterbottom (15), which first part (16) is lowered on the waterbotton (15) after lifting the floating apparatus to free it from the waterbottom and after displacement to a place with deeper water. There the next part (17) is made upon the still deeper water, lowered again until they rest on the bottom, after which the next part is made and so on until the final height and destination are reached. The floating apparatus is completely equiped (10, 11, 14) for performing the work and has a construction such, that it can be disengaged from the finished structure.