Session: 01-04-01 Design & Analysis-I

Paper Number: 123644

123644 - Numerical Study on Seismic Performance of Jack-Up Platform for Operation Safety 

Jack-up platforms are mobile offshore structures equipped with legs, enabling them to elevate above sea level and rest on the seabed during operations. With the increasing demand for offshore activities, there are often no viable alternatives but to deploy offshore platforms in seismically sensitive regions. In areas prone to significant earthquakes, it becomes crucial to thoroughly assess the platform's performance under seismic loads. This evaluation is not only vital for ensuring operational safety but also for reducing operational costs by maintaining an uninterrupted operating window.

This research employs a parametric study approach to evaluate the earthquake response of a mobile jack-up platform operating within a seismically active area under various operation conditions, including seabed soil conditions, and water depth. To achieve this, we developed a representative 3D finite element model of a jack-up platform. This model captures the structural property which can simulate responses accurately. Since Jack-up is a bottom-supported offshore structure, it is important to note that seabed soil condition and the corresponding interaction of spud-can foundation and soil will significantly affect its dynamic response. To address this challenge, we incorporated spring elements into our model to represent the stiffness of the spud can foundation, in accordance with the guidelines provided by ISO 19905-1.

Subsequently, we developed the seismic acceleration design response spectrum based on the site-specific information, including the seismic zone and soil conditions. We applied the response spectrum analysis approach, in compliance with ISO 19901-2 design code, to perform the seismic assessment of the jack-up platform.

As part of the research, we conducted sensitivity studies to explore the influence of operation conditions, such as seabed soil property, and platform elevation, on the platform's seismic response. These sensitivity studies provided a deeper understanding of how these factors can affect the behavior of jack-up platforms during seismic events. The insights gained from these studies have direct implications for enhancing both the design and operational safety of jack-up platforms, especially in regions vulnerable to seismic activity.

In summary, the knowledge and findings derived from this research offer practical applications for improving the design and operational safety of jack-up platforms, particularly in areas where seismic activity is a concern.

Presenting Author: Xuejun Wang Institute of High Performance Computing (IHPC), Agency for Science Technology and Research (A*STAR)

Presenting Author Biography: Dr. XueJun Wang earned his Ph.D. in Structural & Computational Mechanics from Nanyang Technological University, Singapore. With over 15 years of experience, he has led research and development efforts, as well as the design and analysis of marine and offshore structures. Presently, he serves as a principal scientist in Engineering Mechanics at IHPC, A*Star.

Authors:

Xuejun Wang Institute of High Performance Computing (IHPC), Agency for Science Technology and Research (A*STAR)
Zhuangjian Liu Institute of High Performance Computing (IHPC), Agency for Science Technology and Research (A*STAR)
Teck-Bin Arthur Lim Institute of High Performance Computing (IHPC), Agency for Science Technology and Research (A*STAR)
Chang Wei Kang Institute of High Performance Computing (IHPC), Agency for Science Technology and Research (A*STAR)