Concrete and Other Alternative Platform Designs

Abstract

ABSTRACT The paper is chiefly devoted to the design, construction, installation and maintenance of concrete platforms. A review is given over the fixed concrete gravity platforms installed or under construction in the North Sea and elsewhere. The principles of design and construction is discussed with emphasis on –current design requirements and practice–evaluation of environmental loads foundation stability and geotechnical aspects–construction, tow-out and instal-1ation–aspects of inspection and maintenance. The potential of applying concrete platforms for a range of water depths and soil conditions is discussed. Alternative fixed and floating concrete platforms for deep water and concepts which will not need sheltered, deep water for construction are outlined to some extent. The experience from construction and operation of concrete platforms until now is summarized and certain design problems are looked into. The paper concludes that prestressed and reinforced concrete, when designed and constructed in compliance with current criteria, is a well suited, durable and practically maintenance-free material for platforms exposed to the environmental conditions of the North Sea. As for alternative platform designs other than concrete and conventional jackets, a review is given of platforms presently proposed. However brief, the review covers compliant and articulated towers, vertically moored platforms and tripod towers for deep water and hostile environment.