Proceedings of the Thirty-second (2022) International Ocean and Polar Engineering Conference
Shanghai, China, June 5–10, 2022
Copyright © 2022 by the International Society of Offshore and Polar Engineers (ISOPE)
ISBN 978-1-880653-81-4; ISSN 1098-6189

www.isope.org

Linear Springing Assessment of Ultra Large Container Ships
Ye Lu1, Juan Liu2, Bei Teng3, Chao Tian1, Hailong Si1, Xinyun Ni1
1. China Ship Scientific Research Centre, Wuxi, Jiangsu, China;
2. Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
3. Wuxi Institute of Communications Technology, Wuxi, Jiangsu, China(Wu, 1984), and from linear (Du, 1996) to nonlinear (Wu, 1997, Tian,2007 and Ni, 2018), which provides a more consistent and rational
method for evaluating the motion, wave load and structural response offlexible offshore floating structures. It has been widely developed andapplied in the field of marine engineering, such as super-large floating
bodies, large ships, and high-performance multi-body ships.

ABSTRACTAt present, with the development of large-scale and high-speed marinetransportation, the demand for ultra-large container ships of 20,000 TEU
and above has increased sharply in recent years. For such large-open
ships with a length of 400 meters and high-strength steel, the flexibilityof the hull has increased. As a result, the natural frequency decreases,
and the wave encounter frequency increases during high-speed
navigation. This will induce linear or nonlinear wave-induced vibration,
which will seriously affect the fatigue life and navigation safety of thehull. It has attracted widespread attention in the industry and academia
in the world. The springing phenomenon is one important issue that shallbe considered in the structural design of ultra large container ships. Since
it brings severe influence on the ship structure fatigue life and navigation
safety great attention has been drawn from the fields of international
industrial fields and academic circles. In this paper, taking into accountthe influences of the springing effect, the motions equations of an ultra
large container ship has been solved by using COMPASS-THAFTS
software which is developed by CSSRC and CCS based on threedimensional hydroelasticity theory. Meanwhile, the additional mass,additional damping and wave excitation forces are obtained, and themovement and wave load of the container ship are calculated and tested,focusing on the linear wave-induced vibration phenomenon and thegeneration conditions.

At present, with the development of large-scale and high-speed maritime
transportation, the demand for super-large container ships with
20,000TEU containers and above has increased sharply in recent years.
For such large opening ships with a length of 400 meters and theapplication of high-strength steel. The increase of hull flexibility leads tothe decrease of its natural frequency, and the increase of wave encounterfrequency during high-speed navigation, which will induce linear or
nonlinear wave-induced vibration, which will seriously affect the fatigue
life and navigation safety of the hull, which has attracted extensive
attention in the international industry and academia (Kim, 2012, 2014
and Yang, 2020). Therefore, China Ship Scientific Research Centre
initiated and organised the international joint industry project ": CSSRC20,000TEU JIP" in 2018, aiming to establish the benchmark test databaseof wave-induced vibration of super-large container ships, and carry outthe international calculation and comparative study of fluid structures
coupled hydroelastic responses. Based on the three-dimensionalhydroelastic theory, the wave-induced vibration response of thecontainer ship is calculated and analysed by using COMPASS-CRAFTS
application software.

KEY WORDS: Hydroelasticity; ultra large container ship; motion
response; vertical bending moment.

In this paper, a containership investigated has a length of 400 meters,
which had the self-propelled capability, with a speed of no less than 23knots. Therefore, it becomes flexible even in the mild sea statement.
Thus, the hydroelastic responses and structural safety are needed toassess.

INTRODUCTION
The load on a ship sailing in waves and the damage caused by it are
dynamic processes. From the perspective of fluid structures coupledhydroelastic analysis, it is not only reasonable and innovative in theory,
but also has important engineering application prospects to deeply study
and reveal the safety of ship hull in large waves. Since its establishment
in the late 1970s, ship Hydroelasticity theory (Bishop, 1979) has beendeveloped from two-dimensional (Bishop, 1986) to three-dimensional

THREE-DIMENSIONAL HYDROELASTIC METHOD
In 1984, Yousheng Wu pioneered combining the 3D potential flow
theory with the 3D structural dynamics theory to establish the 3Dhydroelasticity theory. Assuming that the ship moves and deforms

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