Hydrodynamic Loading of Steel Structures
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 110, Issue 4
Abstract
Measured jacket brace member axial loads are compared with predictions based on conventional static structural analyses. The measured to predicted member load ratios are shown to be lognormally distributed. Slightly conservative predictions are obtained, on the average, using drag and inertia coefficients of 0.7 and 1.7, respectively, and with no consideration of current or marine growth. A study of member loads vs. total wave load (shear) demonstrated that the wave shear distributions can be directly inferred from the member load distributions. For the larger waves, a median or bias of approximately 0.93 was estimated for the wave load with a coefficient of variation of approximately 0.18. A parameter study indicates that the addition of large currents and levels of marine growth, especially if the drag coefficient is increased because of roughness, results in extremely conservative wave load estimates.
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References
1.
Aitchison, J., and Brown, J. A. C., The Lognormal Distribution, Univ. Press, Cambridge, Mass., 1957.
2.
Bea, R. G., and Lai, N. W., “Hydrodynamic Loadings on Offshore Platforms,” Proceedings of the Tenth Annual Offshore Technology Conference, OTC 3064, Houston, Tex., 1978.
3.
“A Critical Evaluation of the Data on Wave Force Coefficients,” Contract Report No. W‐278, British Ship Research Assoc., Aug., 1976.
4.
Geminder, R., and Pominick, G. M., “The Ocean Test Structure Measurement System,” Proceedings, Civil Engineering in the Oceans IV, ASCE, San Francisco, Calif., Vol. II, 1979, pp. 1010–1029.
5.
Haring, R. E., Olsen, O. A., and Johannson, P. I., “Total Wave Force and Moment Versus Design Practice,” Proceedings, Civil Engineering in the Oceans IV, ASCE, San Francisco, Calif., Vol. II, 1979, pp. 805–819.
6.
Heaf, N.J., “The Effect of Marine Growth on the Performance of Fixed Offshore Platforms in the North Sea,” Proceedings of the Eleventh Annual Offshore Technology Conference, OTC 3386, Houston, Tex., 1979.
7.
Hogben, N., Miller, B. L., Searle, J. W., and Ward, G., “Estimation of Fluid Loading on Offshore Structures,” Proceedings, Institution of Civil Engineers, Vol. 63, Part 2, Sept., 1977, pp. 515–569.
8.
Ohmart, R. D., Gratz, R. L., and Mallery, G. O., “Instrumentation Program for Evaluation of Offshore Structure Design,” Preprints of the Second Annual Offshore Technology Conference, OTC 1264, Houston, Tex., 1970.
9.
Ohmart, R. D., and Gratz, R. L., “A Comparison of Measured and Predicted Ocean Wave Kinematics,” Proceedings of the Tenth Annual Offshore Technology Conference, OTC 3276, Houston, Tex., 1978.
10.
Ohmart, R. D., and Gratz, R. L., “Drag Coefficients From Hurricane Wave Data,” Proceedings, Civil Engineering in the Oceans IV, ASCE, San Francisco, Calif., Vol. I, 1979, pp. 260–272.
11.
Sarpkaya, T., and Isaacson, M., Mechanics of Wave Forces on Offshore Structures, Reinhold Publishing Co., New York, N.Y., 1981.
12.
Wirsching, P. H., “Probability‐Based Fatigue Design Criteria for Offshore Structures,” API‐PRAC Project 80‐15, American Petroleum Institute, Dallas, Tex., Feb., 1981.
Information & Authors
Information
Published In
Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 110 • Issue 4 • November 1984
Pages: 448 - 462
Copyright
Copyright © 1984 ASCE.
History
Published online: Nov 1, 1984
Published in print: Nov 1984
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