Offshore Platform Monitoring And Data Analysis

Due to environmental factors, design flaws and human factors, the large-scale structure injury accidents always happen. The structural health monitoring technology plays an important role in the safe operation of large structure. It has been applied in bridges, dams, venues and other large buildings. With extreme environment and longtime service, offshore platforms are always subjected to damages and fatigue failure. Many efforts have been made in the offshore platform monitoring. The monitoring instruments and technology of foreign countries are relatively advanced than those of domestic. Due to differences in structures, the monitoring applications for different platforms will also be different. A lot of FPSOs (Floating Production Storage and Offloading) in Bohai and Nanhai are under threats of damages due to long time service. Therefore, it is urgent to develop the related monitoring techniques. The development of sensors and data analysis technique will be helpful for the offshore platform monitoring.This research is based on the offshore platforms monitoring project cooperated with the CNOOC (China National Offshore Oil Corporation), includes the studies of offshore platform monitoring contents, techniques and the method of data analysis. An integrated monitoring scheme was proposed, which combined entirety monitoring and local monitoring, variety of sensors have been used, not only the numeric sensors but also video supervising equipment. An integrated monitoring system was developed to collect the data from all sensors. The system has been used to monitor the environment loads and structure response of three FPSOs in Bohai Sea. The monitoring data have been analyzed through kinds of method. A time-varying modal parameter identification method was proposed to analysis the modal parameters of the single point mooring system. This will help to detect the damage of the system.Now, the monitoring project for three platforms is still going, a lot of data have been collected. It is helpful for the study of environment and operation state of the platforms. The results of the data analysis are useful in guiding the platforms to work safely. It also offers good reference for the domestic offshore platform monitoring study.