Investigating the Behavior of Jacket Offshore Steel Structure under Blast Loading

Given the hostile nature of offshore environments, ensuring the structural stability of offshore platforms is crucial to their design. A computer program was developed for the preliminary stability analysis of offshore platforms under significant environmental loads. The program output was applied to a minimum facility platform under extreme storm conditions, providing insight into its structural resilience. A comprehensive framework for experimental studies of the platform's stability was also established using a scaled physical model. This research investigates the effect of blasting loads and the distance of explosions on Steel Jacket Type Offshore Platforms (JTOPs) in both air and water environments. Simulations were conducted using Abaqus 2023, where four blasting loads (1, 2, 5, and 10 tons) were applied at varying distances (10, 20, 50, and 100 meters) from the structure. Results indicate that in water, the blasting wave increased by over 11 times as the distance from the platform increased, highlighting the significant amplification effect of the water medium. In contrast, the influence of the blasting load was considerably reduced in air, suggesting a notable difference in the platform’s response to underwater versus atmospheric explosions. The displacement over time for different blast scenarios. At 0.5 seconds, the main model (2,000 kg at 20 meters) recorded the highest displacement, around 1.65 meters. Case 1, 2, 3, and 4 follow with displacements of approximately 1.35 m, 1.2 m, 0.95 m, and 0.7 m, respectively. Results indicate that displacement increases with higher blast loads and proximity, particularly in the water medium.