Time-History Response Analysis of Jacket Offshore Platform due to Water Level Variation and Safety of Structural Members

Abstract:

Jacket structures are designed for a specific water level (LAT). One of the important issues about these structures is the water level rise. For example, the level of water in the Caspian Sea has risen by 2.5m in the last fifteen years and is continuing to rise. The aim of this study is to investigate the behavior of one typical shallow or medium water jacket platform (a four-leg steel jacket platform in 55m water depth) under water level rise and to evaluate utilization factor of different element at different elevations. In this paper the finite element method (ANSYS) was used for the purpose of modeling of the structure. This paper discusses the effect of water level variation acting on the jacket structure and illustrates subsequent results of the stress utilization within the structure elements. The results of time history analysis show that the initial design water depth (before water level rise) has a basic role on the subsequent behavior of structural elements.

• Periodical: Advanced Materials Research (Volume 601)
• Pages: 280-288
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.601.280
• Online since: December 2012
• Authors: Mohammad Ali Lotfollahi-Yaghin, Roghayeh Rezaei
• Keywords: Jacket Platform, Time History Analysis, Utilization Ratio, Von-Mises Stress

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