Dynamic amplification of jack-up platforms subjected to non-Gaussian wave loads

Journal Article · · Journal of Research of the National Institute of Standards and Technology; (United States)

DOI:https://doi.org/10.6028/jres.099.043· OSTI ID:6660643

Jensen, J J ^[1]

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1. Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Ocean Engineering

The jack-up drilling rig concept has proved to be very convenient in the exploration for oil and gas in offshore areas. Jack-up platforms are sensitive to dynamic amplification in waves because their fundamental period can be as high as 7 s--8 s. Whereas the dynamic motion of the platforms is rather well described by linear theory the excitation depends nonlinearly on the wave height. The stochastic wave loading is thus far from being normally distributed. In this paper dynamic amplifications obtained by the diffusion theory extended to cover nonnormal excitations are compared with available time simulation results in irregular seaways. Generally, the time simulations seem to yield responses less nonlinear in the wave heights than the responses estimated from the diffusion theory. Explanations for these discrepancies are discussed and mainly attributed to a proper choice of total damping.

• OSTI ID: 6660643
• Journal Information: Journal of Research of the National Institute of Standards and Technology; (United States), Journal Name: Journal of Research of the National Institute of Standards and Technology; (United States) Vol. 99:4; ISSN 1044-677X; ISSN JRITEF
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200 -- Petroleum-- Reserves
Geology
& Exploration
03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
42 ENGINEERING
423000* -- Engineering-- Marine Engineering-- (1980-)
DRILLING EQUIPMENT
DRILLING RIGS
DYNAMIC LOADS
EQUIPMENT
FUNCTIONS
GEOLOGIC DEPOSITS
MINERAL RESOURCES
NATURAL GAS DEPOSITS
OFFSHORE PLATFORMS
PETROLEUM DEPOSITS
PROSPECTING
RESOURCES
RESPONSE FUNCTIONS
WAVE FORCES