IN-PLACE ANALYSIS OF OFFSHORE JACKET PLATFORM FOR DIFFERENT WAVE DIRECTIONS
Keywords:Dynamic Response, Regular and Irregular Wave, Pm Spectrum, Morission’s Equation, Airy’s Teory, Deterministic Wave, Random Wave, Mode Shape, Frequency
Offshore jacket platforms are subjected to variety of forces during their life period. To resists all kinds of forces, the structural elements should be designed properly to have safety and economy. In order to fulfil this purpose, the structure should be analyzed with great care.
As the improvement of oil and gas moves into more profound water, in any case, taller stages with longer periods are fabricated that react all the more powerfully to extraordinary waves. Expectation of the dynamic reaction of such structures in extraordinary ocean states is in this way an essential plan thought. Standard waves have all their vitality lumped at a couple of particular frequencies and can, in this manner, cause wrong powerful enhancements, particularly if these frequencies happen to be near the regular frequencies of the structure. In any case, waves in the ocean are exceptionally sporadic and can be best depicted as directional range, which indicates the appropriation of wave vitality as for recurrence and heading, and is most appropriate for the examination of structure in recurrence space technique. For this situation the nonlinear drag is linearized and utilized in the Morison's condition. This guess is proper for the littler, operational sort waves considered in weariness counts, in light of the fact that the powers because of these waves are overwhelmed by the direct idleness part. Various kinds of investigations related with the coat stage ought to be performed to figure the reaction of the structure and measurement the components of the structure. Here an endeavor has been made to complete various examinations to comprehend the dynamic conduct of coat stages subject to different stacking conditions in various ecological conditions. Coat set up investigation was performed, both static and dynamic hypothetically fixed base stage.
With the ongoing imaginative thoughts of investigation utilizing programming, it is presently simpler for the seaward architects to do disentangled and sensible assessment of the static operational and extreme point of confinement state qualities of format or coat stages, which are exposed to different ecological conditions. The essential auxiliary parts of coat type seaward structures including topsides, coat, heaps and the encompassing soil are viewed as utilizing SACS programming various types of investigations identified with coat stage according to API code prerequisite.
American Petroleum institute (2000). Recommended Practice for Planning, Designing and constructing Fixed Offshore Platforms –Working Stress Design .21st ed. Washington API.
C. H. Jo. K.S.Kim ,S.H Lee Parametric Study on offshore jacket Launching Dawson T.H (1983). Offshore Structural Engineering Englewood Cliffs: Prentice Hall.
D.V. Reddy, A. S. J Swamidas, S. Reddy, Offshore Structures, vol.1 by D.V. Reddy and M. Arockiasamy Gaithwaite.J.(1981). The Marine Environment and Structural Design. New York:Van Nostrand Reinhold Company.
Gerwick, B.C,1986. Construction Of offshore structures. John Wiley and Sons,inc, KAIST-a,1985. Development of Design technology of Offshore Platforms for Offshore Oil Production. Glinter clauss, Eike Lehmann & Carsten Ostergaard, offshore structures vol .1
J.L. Alamilla, D. Campos, C. Ortega, a. Soriano, J.L. Morales, Optimum selection of design parameters for transportation of offshore structures F.H..H. A Quadvlieg A.B.Aalbers ,R.P Dallinga,C.E.J. Leenars Voyage
Acceleration climate: A New method to come to Realistic Design Values for Ship Motions Based on the Full Motion Climate for a Particular Transport
Knight, R.M. and Daniel, J.J.S. (1993). World Trends in Major Offshore Structures 1970-1999. Proceeding of the 3rd International Conference on Offshore 93: Installation of Major Offshore Structures and Equipments. February 17-18. london: IMarE/RINA,17-23.
S. Chakrabarti (Ed.) Handbook of Offshore Engineering
Engineering dynamics, SACS manual ,2004