The Integrity Management Of Jacket Offshore Platform Structure During Service

Our country has a long coastline,and its sea area is rich in oil and gas resources.Facing the rapidly developing economy,offshore oil and gas resources are related to the development of China's industry.China's offshore oil and gas exploration has completed a relatively complete system according to different sea areas and related requirements,After decades of development.The fixed jacket platform has the advantages of short manufacturing cycle,simple structure and high safety.At present,there are about 280 offshore platforms in China,such as the South China Sea,Bohai sea and the East China Sea.The Department investigation shows that the aging of the fixed jacket platform is serious,which is difficult for the safety management of the large structure during the operation period.Therefore,the integrity management of fixed offshore platforms during operation is of great significance to ensure the safe operation of the platform.According to the basic process of the integrity management of offshore jacket platforms,the main contents of this paper are as follows:The static,spectral fatigue and collapse of offshore platforms are analyzed which analyzed using SACS ocean engineering analysis software.The static analysis and verification platform is used to check the strength of members and joints under normal working conditions.Fatigue analysis mainly analyzes whether the life of platform components meets design requirements and whether it can operate safely during service.The collapse analysis mainly analyzes the progressive collapse mechanism of the platform,and the reserve strength of the checking platform is up to the standard.It assess the safety status of the platform during service and screen out vulnerable parts to prepare for risk inspection.According to structural safety assessment,It can be obtained which fatigue points,rods and joints that do not meet the corresponding requirements.In this paper,the quantitative RBI analysis used for the fatigue point: the fatigue failure probability of the platform structure is calculated by the equivalent Weibull distribution method.The fatigue damage of each sub sea state is calculated by SACS,After calculating the fatigue damage of each sea condition by SACS,the characteristic parameters of the Weibull distribution function can be obtained,and the fatigue failure probability can be obtained by the reliability analysis method.After calculating the RSR and RCR values of the platform structure by SACS,the failure probability of the collapse of the platform structure is calculated by the integral method of the environmental load exceeding the limit state of the structure resistance.In this paper,semi quantitative RBI analysis is used for joints and joints.The failure consequences are determined according to the economic security of the platform.The failure probability is calculated by the collapse failure probability.According to the risk inspection,the corresponding inspection plan can be obtained to guide the safe operation of the platform.In this paper,the verification of relevant examples of integrity management principles is well arranged,which can guide practical engineering applications.The validation of the example is not extensive,and the calculation method of collapse is limited,so we need further research.