STRUCTURE DESIGN AND RELIABILITY ANALYSIS OF FLARE TRIPOD PLATFORM AT NATUNA SEA

• Main Author: DWI ASTUTI ( NIM 15513056 ), FEBRIANA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/22125
• Institution: Institut Teknologi Bandung

Offshore platform structure is designed to receive dead loads, live loads, and environmental loads specific to each platform. One of the international standards used to design such structures is API RP-2A. API RP-2A is divided into two types based on the loading method, namely WSD (Working Stress Design) and LRFD (Load Resistance Factor Design). <br /> <br /> Structure designed with LRFD method is considered to be more economical. However, the LRFD RP-2A loading method incorporates environmental load factors in the North Sea that may not be suitable for structures in Indonesian. To find out the strength of the structure, three structural designs were analyzed in inplace, seismic, and fatigue analysis to test the strength of structures in static, quake, and cyclic loading conditions. <br /> <br /> Checking conformity of load factor with LRFD principle can be done with reliability analysis. This analysis uses Monte Carlo simulations by generating random variable loads in the form of significant high and wave periods that represent wave data at structural location and random variable capacity in the form of material yield stress based on ISO 19902 Fixed Steel Offshore Strucure reference. The reliability analysis was performed on the critical member of the structure to obtain the reliability index (&#946;) with the member stress condition in inplace analysis with SACS software according to API RP-2A LRFD 1993 in 50 simulations with 50 sets of high data and wave period and 50 sets yield stress data. From the simulation process will be obtained 50 UC values for each category of bracing, deck, jacket leg, and pile. The distribution parameters of 50 UC values in each category are used to determine the reliability index value so that it is considered to represent the structural reliability index in Natuna Sea.