... for space-frame structures is valid for dynamically sensitive structures. All of these effects can be captured using our numerical porous block model. production logging experiment wave group hydrodynamic force morison equation focussed wave group wave-current blockage space-frame offshore...

..., to measure surface elevation profiles and the velocity beneath extreme crests. Focused wave groups representing the extreme events were generated at a given point in space and time. The input amplitude spectra for the flap-type wave maker were derived using Tromans’ NewWave theory which corresponds...

...OTe 8360 Impact Forces on a Jacket Deck in R~gula.r Waves and Irr~gular Wave Groups . J.J. Murray, F.N. Winsor, Institute for Marine Dynamics, National Research Council and P. Kaplan, Hydromechanlcs Inc. © 1997, Her Majesty in Right of Canada, All rights reserved, National Research Council 01...

... to the individual waves and mean and low-frequency second order wave drift forces related to wave groups. From the point of view of the design of mooring systems both first and second order wave loads and the motion and mooring load response need to be taken into account. At the design stage predictions...

... devices. These recordings include the growth, peak and decay of a severe winter storm. A comparison is made between the wave parameters obtained from the two devices. This includes first order wave spectra and their derived height and period parameters as well as the most commonly used wave grouping...

... included in the motion analysis. The theory is extended from regular waves to apply to irregular waves. The test consisted of measuring the six degrees of motion of the cylinder and the loads in the mooring lines in regular waves, wave groups and irregular waves. The theoretical results are correlated...

... series and the springs were pretension so that they never went slack. The tests included the regular waves, wave groups and the irregular waves. The motions of the floating vessel and the loads in the mooring lines were measured. The steady wave drift force on the model and the long period oscillating...

... on the wave gauges in a·typical ex- periment are shown in Fig. 5. The experiment lasted for 27 seconds. Both individual waves and wave en- velopes are shown in true time scale. The modulation of the wave group and the final generation of an ex- treme wave at gauge 3 are clearly visible in the figure. In a few...

... of the structure has been considered only. Theory and results from labora- tory tests will be explained, applying regular waves, regular wave groups and irregular waves as well. I;; = amplitude of incident wave Ba = breadth of" the structure f = frequency (inverse of the wave period) The expression (1) indicates...

... ABSTRACT Statistical parameters are derived that describe the occurrence probability for the number and height of consecutive waves in a group, which are large compared to the average wave height. Such wave groups can create extreme forces in mooring lines of large vessels. All...

... of an earlier executed program[1]. It will be shown that, using the results of measured or calculated drifting forces on an object moored in regular waves, a prediction can be made of the drifting forces induced by wave trains consisting of regular wave groups. Also for an irregular wave train the drifting...