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

Research on the Comfort of Offshore Trestle under the Coupling Effect of Wind, Wave, and Current
Chao ZHU, Dawei SHEN, Yideng LIANG
Guangdong Provincial Highway Construction Corporation. Huangmaohai Link Administration Centre.
CCCC Highway Bridges National Engineering Research Centre CO., Ltd.
Guangzhou China. Zhuhai China. Beijing China.

environmental loads, the research on bridge disaster prevention andmitigation technology in China is developing from the direction ofsingle-factor disaster to the direction of multi-hazard coupling (Zhang,2016). At present, many studies have been carried out on the couplingmechanism and damage of the wind-wave-current coupling effects (Dai,2020; Lie, 2016; Papinutti, 2017). There are few literatures on theinfluence of wind-wave-current coupling effects on the comfort ofoffshore bridges. On the basis of fully considering the coupling effectof wind, wave and current, this paper takes a sea-crossing trestle in theHuangmaohai Sea as an engineering example, and establishes adynamic analysis model for the structure of the trestle on the sea under
the combined action of wind, waves and currents to analyze thedynamic response of the trestle structure under different wind, wave
and current characteristic parameters, and establishes the relationshipbetween the characteristic parameters of wind and wave currents andthe comfort of the trestle construction environment to evaluate thecomfort of the trestle construction environment.

ABSTRACT
In order to investigate the influence of wind, wave current coupling on
the comfort of offshore trestle construction environment, a dynamic
analysis model of offshore trestle structure is established to analyze theinfluence law of wind, wave and current characteristic parameters on
the comfort of trestle construction environment. The research results
show that parameters such as water depth, wave height and wind speed
have a significant impact on the comfort of the trestle construction
environment. Under the coupling effect of wind, wave and current, theconstruction environment of the trestle bridge at high water level ismore likely to make people feel uncomfortable.

KEY WORDS: offshore trestle; wind-wave-current coupling; finite
element analysis; comfort; dynamic response

INTRODUCTION

WIND-WAVE-CURRENT LOADS

When studying the destructive effect of environmental loads on bridge
structures, the influence of environmental loads on the comfort ofpedestrians on the bridge should also be considered. Under theexcitation of moving loads, the bridge vibration will bring discomfort
to the people on the bridge. For example, when the Millennium Bridge
in London opened in 2000, the large vibration of the bridge causedpanic among the pedestrians on the bridge, and the traffic had to be
temporarily closed (Dallard, 2001). Scholars have carried out a lot of
research work on the vibration comfort of bridges. Sekulic (2019)studied the influence of pontoon movement on the comfort of bus
passengers. On pontoons, passengers also feel less comfortable at lower
bus speeds compared to stationary surface roads. Zhou (2016)
established a wind-vehicle-bridge coupled vibration model to study thecomfort of people while driving on a cable-stayed bridge. Uyttersprot(2021) considered the damping effect caused by pedestrians, andstudied the comfort of web-core sandwich panel FRP composite
footbridges.

Most of the common waves at sea are caused by the sea wind, and there
is a close connection between the sea wind, waves and currents, andtheir coupling effects should be considered when analyzing wind, wave
and current loads.

Wind Loads
Natural wind can be divided into two components: average wind andpulsating wind (Xiang, 2005). The average wind refers to the windspeed and wind direction that hardly change with time in a time intervalof more than 10 minutes, and the wind speed can be obtained fromlocal observation data. The pulsating wind is an irregular part of thenatural wind, and its intensity varies randomly with time and space.
The wind loads used in the analysis in this paper are based on the
Davenport pulsating wind power (Davenport, 1967; Wang, 2018)
spectrum and are generated by numerical simulation using theharmonic filtering method.

Marine bridge engineering faces many challenges, not only in the longterm strong corrosion environment such as high humidity, salt damage
and sea fog, but also in the face of natural disasters such as typhoons,huge waves, jets and earthquakes (Huang, 2020). In view of the marine

The Davenport spectral expression is:2079