Non‐Gaussian Response of Offshore Platforms: Dynamic
Publication: Journal of Structural Engineering
Volume 113, Issue 9
Abstract
A hybrid method, consisting of spectral and probabilistic analysis techniques, is proposed to evaluate the dynamic response characteristics of offshore platforms considering nonlinear wave kinematics and free‐surface fluctuation effects. The effect of nonlinear wave kinematics and intermittent loading is that the wave loading is non‐Gaussian. The response of platforms to such non‐Gaussian loading will be non‐Gaussian. A combination of spectral and probabilistic analyses is developed to estimate the response up to the fourth moment. The probability distribution of the response is estimated as a mixture of Gaussian distribution and shifted exponential distribution. With the help of an example, it is shown that the free‐surface fluctuations have a significant effect on the response. The skewness and kurtosis are shown to increase with an increase in significant wave height. The probability distribution is shown to deviate from the normally assumed Gaussian distribution, particularly at the tails commonly found in full‐scale measurements.
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Information & Authors
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Published In
Journal of Structural Engineering
Volume 113 • Issue 9 • September 1987
Pages: 1882 - 1898
Copyright
Copyright © 1987 ASCE.
History
Published online: Sep 1, 1987
Published in print: Sep 1987
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