... Abstract Line breakage events have been experienced on moored structures during recent years. These are often occurring in heavy weather and overload is one of the reasons pointed out. The present paper identifies posible physical phenomena that may lead to wave forces higher than predicted...

... for the structural reassessments of the Ekofisk Platforms. The hydrodynamic model/software tool calculates the wave forces using a load recipe based on the concept of change of fluid momentum taking into account the additional effects from buoyancy and drag. Due to the presence of the great Ekofisk Barrier...

... linearized models. A frequency decomposition of the wave forces on a structure indicates that even for a regular wave, higher harmonic components are present due to non-linearities. Therefore, SDOF method severely overestimates the inertia forces near the natural period, while possibly underestimating...

...OTC 8065 Model Test of Wave Forces On A Structurally Dense Jacket Platform G. Z. Gu, M. A. Parsley*, E. P. Berek, J. J. Calve, R. C, Johnson and D. J. Petruska MEPTEC, Mobil Technology Company, Dallas, TX 75244 Copyrght 1996, OFFSHORE TECHNOL@Y CONFERENCE This paxr was p+epared ICNpmseniatlon...

... water depth. Tests were conducted in extreme (breaking) random waves both with and without in-line currents. Based on analysis of 138 extreme waves, it was found that predicted in-line fluid velocities were 6% larger than measured values on average, while predicted in-line wave forces and moments were...

... report describes an investigation quantifying to what extent the springing excitation on a tension leg platform can be fully described by quadratic wave forces, or whether third and/or higher order forces make a significant part of the excitation. The applied method of investigation consists in comparing...

... proc otc 7140 capacity effect deck wave force spectra performance otc 7140 overload ratio upstream oil & gas platform offshore platform displacement performance characteristic earthquake subsea system time history ductility demand loading wave force ductility spectra...

... calculation procedure engineering impact damage wave force procedure accuracy force calculation procedure task group offshore tubular offshore structure equation assessment energy absorption otc 7152 strength tubular member upstream oil & gas geometry offshore technology...

... of the second-order wave forces and free surface elevation around the structure. The force maxima and runup are thereby obtained deterministically. As an illustration of the method, the special case of a bottom-mounted surface-piercing circular cylinder subject to a specified wave record is examined...

...OTC 6520 Wave Forces on Rectangular Cylinders at Low Keulegan-Carpenter Numbers D. Hamel-Derouich, U. of Glasgow Copyright 1991, Offshore Technology Conference This paper was presented at the 23rd Annual OTC in Houston, Texas, May 6-9. 1991. This paper was selected for presentation by the OTC...

... that the presence of structural response velocities in the wave force for- mula acts as a response reduction mechanism [1]. This proves the existence of hydrodynamic damping related to the flow- separation processes which occur in the fiuid near the sub- merged structure. In the vicinity of a natural frequency...

... ABSTRACT The effect of pipe gap and roughness on wave forces was studied offshore ofHonolu1u using a special pipe rig. Test swell involved a local hurricane as well as distant storms. This paper emphasizes peak horizontal and vertical forces. A new technique, using previous flow history...

... of the wave forces on large diameter cylinder submitted to impact loads. A bibliographic review showed that there had been many pUblications dealing with the problem of wave impact loads. that the theory was really well established, and that model tests had been conducted. However, the studies and model tests...

...aTC 6409 Wave Run-Up and Wave Forces on a Truncated Cylinder J.M. Niedzwecki and A.S. Duggal, Texas A&M U. Copyright 1990, Offshore Technology Conference This paper was presented at the 22nd Annual OTC in Houston, Texas, May 7-10, 1990. This paper was selected for presentation by the OTC Program...

... ABSTRACT Wave force on deck beams are not usually a consideration in offshore platform design. An air gap is provided between the crest of the design wave and the lower deck. Therefore, no standard procedures for predicting wave forces on deck beams have been developed. Large platform...

.... At the time of the measurements, the significant wave height had declined from a maximum of 28 feet to 23 feet, but the sur- face current had increased to 3.0 feetfsec. The wave force model used in this study has been described by Rodenbusch and others, and is based on random d~ectional wave theory...

... current marine installation. 1. INTRODUCTION Because of non-linear effects it was not possible to perform a numerical analysis to determine the wave forces and motion responses during the different construction, installation and in-service phases of the Protective Barrier, it was therefore necessary...

... which carries the pipe, and six side aprons, designed so that the sections could be installed by a salvage vessel and connected underwater. otc 5852 submarine pipeline hydrodynamic force morison equation midstream oil & gas frequency test section wave force coefficient spectrum...

... ABSTRACT Measured wave force data from the Conoco Test Structure in hurricane Carmen have been analyzed on a wave by wave basis to determine the total hydrodynamic forces exerted on the platform. These measurements are compared with calculated total forces. The calculated forces are based...

... coefficient computer analysis matrix mooring system wave force crane vessel sscv dynamic behaviour upstream oil & gas operation otc 5819 OTC 5819 Computer Analysis of Heavy Lift Operations by H.J.J. van den Boom, J.N. Dekker, and R.P. Dallinga, Maritime Research Inst. Netherlands Copyright...