Structural corrosion modeling for reserve strength assessment of fixed jacket platform

The response of a fixed offshore platform subjected to extreme wind and wave loadings (lateral loads) under corrosion conditions is studied. In this research the offshore jacket structures are modeled as a frame structures with fix-end condition since the foundation is using pile foundation. The performance of structure and will be checked using pushover analysis to get the performance level of structure during several response spectra of earthquake. The modeling and non-linear pushover analysis was done using SACS. The corrosion was applied on the structure and will be modelled in localized area based on inspection data. The performance of structure against non-linear pushover analysis is normalized as a capacity spectrum and three response spectrums were normalized as demand spectrum. Based on these curves the performance level of structures can be known and the differences between each response spectrums also shown in this research. Through the pushover analyses using SACS, the relation between time and residual strength was established and it was verified which zone had more corrosion influence to the jacket structure.