DESIGN AND LIFTING ANALYSIS OF FOUR-LEGGED FIXED OFFSHORE PLATFORM IN JAVA SEA

• Main Author: Haryo Aflam, Rais
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/77109
• Institution: Institut Teknologi Bandung

Indonesia as a maritime country has a larger sea area than its land area. So it is undeniable that Indonesia has the potential for marine resources that are quite abundant, one of which is oil and gas, which until now has increased demand every year. To fulfill this demand, it is necessary to carry out exploration and exploitation activities at sea using infrastructure in the form of offshore platforms. In this Final Project, the modeling of a four-leg fixed type offshore platform structure located in the Java Sea region with a depth of 50 meters is carried out with environmental load parameters derived from environmental data processing obtained from the secondary data database of hindcasting results. In the design process of a fixed type offshore platform, an analysis is needed to determine the feasibility of the structure due to the loads acting on the structure. The analysis carried out includes in-place, seismic, and fatigue analysis. In addition, further analysis is also carried out in the form of topside lifting analysis. The analysis conducted refers to the API RP 2A-WSD standard, AISC Manual of Steel Construction, and GL Noble Denton. Based on the results of the in-place analysis, the designed structure can withstand operating and storm conditions after checking the member stress (member UC), joint strength (joint can), vertical and horizontal deflection, and maximum capacity of the piles. There are also seismic analysis results, where the designed structure can withstand when given strength level earthquake (SLE) and rare intense earthquake (RIE) earthquake loads after examining the member stress (member UC), joint can strength, and maximum capacity of the piles. In addition, a fatigue analysis of the designed structure was carried out and it was found that the structure could last for 28.67 years with a damage value of 0.52. After the structure meets the criteria for in-service analysis, a pre-service analysis is carried out for the topside structure in the form of a lifting analysis. Lifting analysis is carried out to determine the strength of the structure in the lifting process in balanced and unbalanced conditions. In addition, this analysis will determine the lifting configuration and selection of lifting equipment such as slings, shackles, padeye, and cranes used in the lifting process.