الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The majority of the world′s platforms have been designed according to the different editions of Recommended Practice by The American Petroleum Institute (API).
The first edition of API RP 2A, Recommended Practice for Planning, Designing and Constructing Fixed Offshore Platforms, was released in 1969 Offshore platforms built prior to this date were designed based on a wide variety of criteria and fabrication techniques depending on the operator or the engineering and fabrication contractor.
Many fixed offshore platforms at the Suez Gulf were designed and constructed in the 60s and 70s. As part of the rehabilitation project of Suez Gulf offshore platforms, some platforms were assessed to identify platforms life extension and the possibility to increase deck loads and add new conductors to increase oil production.
The API recommendations require minimum pile factor of safety (FoS) of 1.5 for 100 years design period, respectively. It was revealed that some offshore platforms in the Suez Gulf did not satisfy the minimum required safety factors. This led to the decision not to increase deck loads and/or not to add new conductors.
As a result, it is necessary to check whether the latest API design guidelines or the uncertainties in environmental loading contribute in the underestimation of the safety factors of some offshore platforms at Suez Gulf. El Morgan M-100 and Badri-C platforms were used as a cases study. As a preliminary assessment of the platforms, it is indicated that one of them does not satisfy the minimum required factors of safety for 100 year design period. One of the main questions was whether the uncertainty in environmental loading contributes in the underestimation of the piles safety factors.
In this study, assessment of El Morgan M-100 and Badri-C platforms were conducted using the latest API edition (21st edition) and the API 19th edition. There are major differences between the two editions especially in relation to the hydrodynamic coefficients and procedures of wave and current calculations. An intensive parametric study was conducted to investigate the effect of wind speed, wave height, wave period, current velocity and marine growth on the platforms response and piles factors of safety.
Organization and Description of the Thesis
Chapter one: Thesis introduction, problem definition and objectives
Chapter two: Gives a review of different types of platforms, hydro-dynamic challenges, and historical extreme weather hazards and cases study on other types of platforms. It also gives a comparison between newer and older editions of API and between different codes (API, ISO and Norsok).
Chapter three: Gives a review of different types of loads experienced by platforms and presents detail review of (wave and soil) which includes theories and equations.
Chapter four: Gives detailed description of numerical model components (SACS).
Chapters five: Presents a case study of an existing offshore platform (MORGAN M-100) which was originally designed as a four pile satellite platform installed in 101 feet water depth. Also describe the effects of different variables on the response of the platforms are investigated. These variables include two main items. These are the effect of use different editions of API and the effect of different environmental loads (i.e. wind, wave height, wave period, current speed and marine growth).
Chapters six: Presents case study of an existing offshore platform (BADRI-C) which was originally designed as a nine pile satellite platform installed in 222feet water depth. Also describe the effects of different variables on the response of the platforms are investigated. These variables include two main items. These are the effect of use different editions of API and the effect of different environmental loads (i.e. wind, wave height, wave period, current speed and marine growth).
Chapter seven: A summary of the study is presented and general conclusions are drawn. The study introduced assessment of existing offshore platforms and also presents the effect of different editions of API and environmental loads.