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Author
Grigoriu, M. | Alibe, B.
Title
Practical Approximations of Peak Wave Forces.
Coporate
Univ., Cornell, Ithaca, NY
Sponsor
National Bureau of Standards, Washington, DC Minerals Management Service, Reston, VA
Report
NBS GCR 84-481, November 1984, 58 p.
Distribution
Available from National Technical Information Service
Keywords
extreme values | loads | ocean engineering | offshore structures | reliability | waves
Abstract
According to Morison's equation, wave forces acting on cylindrical members have two components: drag forces, which depend nonlinearly on wave particle velocity, and inertia forces, which are proportional to wave particle acceleration. Wave forces are then non-Gaussian processes although fluid velocities are assumed to follow Gaussian distributions. This report develops approximations of the mean of the peak of wave forces during design storms. It shows that the square root of the sum of the squares (SRSS) rule can be applied to approximate the mean of the peak wave force from the average peaks of inertia and drag to inertia forces and frequency content of the wave particle velocity process. The report also provides various descriptors of drag, inertia, and wave forces, including marginal distributions, mean crossing rates, and extreme value distributions.