Structural Analysis Of A Jacket Platform In Fire

As the basis facilities for the offshore oil industry, jacket platforms are widely used in China's sea waters and researched long-term by the Ocean university of China. In this thesis, wholly structural response analysis of a jacket platform affected by pool-fire radiation load is conducted.Firstly, the cause factors of platform pool fire are disused and compared with common building ignition . It comes to a conclusion that because of adverse working environment, platform fires may not be solved by applying building fire models. Specialized pool fire models are demonstrated to analysis large pool fire incidents on offshore platforms. Large pool fires are inconvenient to be characterized wholly using field functions derivation. Hence semi-experienced fire models based on wild fire tests are recommended for solving offshore fire problems. Typically semi-experienced fire parameters to describe large pool fires are briefly introduced and their calculation methods are given in this dissertation.Next, the heat load derived from preceding fire models analysis is applied to a jacket structrue's finite elements model, including nonlinear material properties under high temperature. Then interactively response analysis of the whole plat form structure with both thermal and structural loads is taken. To calculate heat radiation from the fire to the leg, a couple field element is used in this model. This could avoid structural error caused by inappropriate constraint condition such as full directional placement restriction applied at the ends of the component, which method is usually used in a single component's thermal-structural analysis.This dissertation introduces semi-experience fire models which could be applied in platform pool fires and a finite elements analysis method to solve wholly structural response problem while some part of the structure are affected by heat radiation from a pool fire, which may be used in platforms anti-fire engineering.