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

Dynamic response of steel protecting structure for bridge pier against ship impact
considering influence of fluid
Xian Zheng Xue1, Tao Wang2, Wen Zhe Zhang2, Xiao Qiang Zhang 2, Jin Pan2,3, Ming Cai Xu4
1
The Fifth Survey And Design Institute (Group) CO. LTD. of CRCC, Beijing, China
Department of Naval Architecture, Ocean and Structural Engineering, School of Naval Architecture, Ocean and Energy PowerEngineering, Wuhan University of Technology, Wuhan, China
3
Key Laboratory of High Performance Ship Technology, Ministry of Education, Wuhan, China
4
School of Naval Architecture and Ocean Engineering, Huazhong University of Science & Technology, Wuhan, China;

2ABSTRACT

Recent numerical investigations and model experiments aregenerally focusing on the possibility of ship-to-bridge collision(Wang et al., 2014), ship’s impact force towards bridge pier or
bridge pier’s anti-collision device (Peng et al., 1999; Hu et al.,2005; Li et al., 2004; Pan et al., 2012; Pan et al., 2014;
Yu&Zheng, 2010; Wang et al., 2009), impact energy absorption
and conversion between ship and bridge pier or bridge pier’santi-collision device (Liu et al., 2000; Wang et al., 2001; Pan etal., 2005; Fan&Wang, 2005) and so on. These researches
contribute to improving the safety of the bridge and reducing
the damage of the impact ship.

The bridge pier passing rivers is in the risk of vessel impact,which might cause the damage or even collapse of bridge. It
needs to install energy absorption structure to protect bridge.
The steel protection structure of bridge was designed. The
numerical simulation of collision between ship with 1000 ton
DWT (deadweight) and a floating protection structure ofbridges pier is conducted in explicitly dynamic analysis.
Cowper-Symonds constitutive equation is generally adopted toaccount for the influence of strain rate sensitivity for thedynamic characteristics of structure. The fluid-structure
coupling method and added mass coefficient method are both
adopted applied to figure out the influence of the fluid field on
the structural response. The results obtained from the twomethods are compared to investigate the effect of the fluid field
during collision process, including collision force, collision
depth, vertical displacement and internal energy change of theprotection structure. It can be found that when considering thefluid-structure interaction, the maximum collision depth issmaller and the maximum collision force is larger comparedwith those obtained by added mass coefficient method. Thus,
the effect of the fluid field should be considered for thesimulation of floating protection structure of bridge pier.

Because of the rapid development of computer hardware,
especially the advancement and maturity of nonlinear finite
element technology, the numerical simulation technology has
been generally applied in the study of ship-to-bridge collision.
Liu et al. (2000) simulated the process of the collision between
ship and bridge pier by nonlinear finite element program
DYTRAN and the study indicated that the pier’s absorption ofenergy is quite small and could be almost neglected comparedwith the ship’s. Wang et al. (2001) applied the threedimensional elastoplastic analysis model to the simulation ofcollision between ship and bridge pier and found that theprotecting device could avoid direct contact between ship’s
bow and bridge pier. The protecting device absorbed the kinetic
energy of the impactor by its plastic deformation in thecollision process at the same time, so it could protect both ship
bow and bridge pier well. Pan et al. (2005) simulated thecollision process between ship and protecting device throughLS-DYNA and discussed the impact factors of collision
problems such as collision position, collision speed, andstructural size of protecting device, and feasible suggestions forthe design and improvement of the protecting device are put
forward. Fan et al. (2005), Li et al. (2006) and Peng et al.
(2010) simulated the dynamic process of 5000-ton ships
striking different bridge anti-collision steel boxes by nonlinear
finite element method and analyzed the collision force of shipto-bridge, deformation of collision damage, ability of energy
absorption and deformation failure of each component of theKEY WORDS: Vessel; Bridge; Fluid-structure interaction;
Impact; Finite element method
INTRODUCTION
Collisions between bridges and ships are often considered as
special cases of ship-to-ship collisions and researches areusually conducted rely on the theory of ship-to-ship collisions
The research methods include the Minorsky method (Minorsky,1959), Woisin theory (Woisin,1979), Heins-Drucher theory(Derucher, 1982), various simplified analytical methods,
numerical solution for simplifying internal mechanism,
experimental method and finite element method.

3236