Dynamic Response of Offshore Structures – An Overview

Abstract- Offshore Construction is the installation of the structures and facilities on a marine environment, usually for the production and transmission of electricity, oil, gas and other resources. Offshore structures are being challenged to counteract the depletion of oil resources with the new set of discoveries. By 2010, the increase in drilling platforms induced the demand for offshore structures in deep sea. Hence, the quest on the research and development of the deep-water structures has resulted in the recent advancement and thrust in this area. In the design of buildings onshore, it is influenced mainly by the permanent and operating loads, whereas the design of offshore structures is dominated by environmental loads, especially waves and winds, and the loads arising in the various stages of construction and installation. In this paper, the focus is on wind load, introduction to wind load, its effect on offshore structures, analysis procedure and the design considerations of wind load for offshore structures. A case study of Hurricane Andrew has also been studied.

Keywords – Codal provisions, Dynamic effects, Hurricanes, Wind action, Wind Speed

INTRODUCTION

One of the greatest discoveries of 20th century was oil and it has so many applications that it cannot be separated from mankind. The oil exploration has started as early as 1900 and the oil exploration initially was concentrated on land. As the need for oil expands in an explosive rate, need for and new discoveries was eminent. During the middle of 20th century, oil discovery started in near shore and medium range of water depth. The need for qualified offshore structural personnel are rapidly increasing as the oil industry moves into deeper water in the search for additional supplies of oil and gas, new technology is emerging at a rapid peace for the development of new concepts for offshore platforms. Various environmental loads act on offshore structures like wind, wave, current, tides, snow, ice, earthquake etc. The environmental loads affect the safety of the structure and hence, there is a requirement of analysis and consideration in design. The effects of wind loads, the analysis of offshore structures for wind loads and the design considerations have been given [8].
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