Rev. Roum. Sci. Techn. - Mec. Appl., Tome , N o , P. - , Bucharest, 1998 THEORETIC AND EXPERIMENTAL STUDIES FOR DETERMINATION OF WIND LOADS ON OFFSHORE PLATFORM STRUCTURES M. POPESCU * , A. SÎMBOTIN ** The paper presents an approach to the problem of wind loads acting on the above-water structure of the fixed offshore drilling, extraction or storage platforms, using experimental and theoretical methods. The wind action is one of the important loads on offshore platforms. Usually, this action appears simultaneously with wave action. The offshore platform above-water superstructure is a complex structure, which generates many problems relative to estimation of wind loads. For the “template” type platforms, wind loads up to 10% of the whole external loads (waves, wind, currents and earthquakes). Wind loads on above-water offshore platform structure were computed using a mathematical model, based on semi-empirical formulas, which is presented in this paper. The paper presents also the experimental study results obtained on the wave and wind tunnel belonging to The Research and Engineering Institute for Environment from Bucharest. The tests were carried out for the offshore platform PFC-III, designed for the Black Sea Romanian zone of the continental shelf. Some results of tests are presented in graphical form. The paper stresses the need to carry out both theoretical and experimental studies, for the design, in safe and optimal conditions, of the offshore platforms. 1. INTRODUCTION Special efforts concerning the design and construction of offshore platforms for drilling, production, and storage are necessary for the extraction of hydrocarbons in continental shelf of the Black Sea. Adequate designing should be done in order to obtain a workable and economical offshore platform to perform the given function. Wind forces are exerted upon the portion of the platform structure that is above the water (so called superstructure) as well as any equipment, deckhouses, and derricks, which are located on the platform. Generally, the wind intensity is variably in time. Wind velocities for both extreme and normal conditions are required. Although the significance of the wind action is not large as compared with the action of other external factors (like waves and marine currents), because the wind is acting only on superstructure of platform, this action contributes to the total load on platform structure. The design and the construction of an offshore platform, in maximum safety conditions, depend on accurate evaluation of wind, wave and current loads [11]. ______________ * University of Constantza, Faculty of Engineering. ** Research and Engineering Institute for Environment, Bucharest.