Abstract: A means and a method for protecting a sea bottom surface or an installation positioned on same, for instance a pipeline, which means comprises a plurality of pliable concrete plate elements which are flexibly interconnected one after the other and thereby forming a chain-like unit, which chain-like unit is positioned along the sea bottom surface, its flexible characteristics both longitudinally and transversally enabling the unit to adapt itself to transverse and to longitudinal level variations in the course of the laying.

Abstract: A marine structure includes a base which is to be founded upon the sea bed. An elastic pre-stressed column is rigidly fixed to and extends upwardly from the base. A buoyant, rigid structure is fixed to the upper end of the upstanding elastic column. The buoyant, rigid structure includes a submerged part and a part projecting up above the sea level to support a deck superstructure. The pre-stressed elastic column is designed to deflect in a curved manner when the buoyant, rigid structure is subjected to environmental forces. In particular, the first nautral period of the installed structure is longer than the significant exciting wave periods. Accordingly, the main structure will oscillate about its vertical equilibrium when subjected to waves and wind thereby behaving as an articulated column.

Abstract: A method is provided for mounting a deck superstructure, comprising at least one concrete girder and/or beam, on a supporting structure intended to operate in marine surroundings. The supporting structure comprises at least one column which extends above sea level and the method comprises the steps of bringing the deck superstructure, either as a unit or in sections, in position relative to the column, hoisting the deck superstructure up to the final position thereof using cables and a jacking system, and tensioning the cables upon the arrival of the deck superstructure in its final position. The lower ends of the cables are permanently anchored to the deck superstructure while the upper ends of the cables are connected to hoisting and tensioning devices arranged on top of the column.