Proceedings of the Thirty-second (2022) International Ocean and Polar Engineering ConferenceShanghai, 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

Numerical simulation of the capacity of high standard sea dike against extreme storm surge
He Wang1, Zhenhua Pan2, Hua Liu3,4

Shanghai Waterway Survey and Design Research Institute Co., Ltd, Shanghai, China
2
DHI CHINA, Shanghai, China
3
School of NAOCE, Shanghai Jiao Tong University, Shanghai, China
4
MOE Key Laboratory of Hydrodynamics, Shanghai Jiao Tong University, Shanghai, China
1ABSTRACT

coastal floods and their effects (including tide level dynamics,submerged extent and seabed deposition, etc.) through numericalsimulations (Ferreira, 2014, Chen, 2019, Zhao, 2014, Yi, 2017, Chen,
2015). Its series of achievements are of great significance for disasterprevention and mitigation (Kuang, 2015, Wang, 2018).

In order to study the defense capability of the sea dike in Shanghai
under the condition of sea level rise, a two-dimensional storm surge
flood model with integrated sea and land was established. Throughmodel calculation, the following conclusions are given: Under thecondition of sea level rise and extreme storm surge, the main sea dike in
Pudong area and Changxing Island area have overflowed. The designed
protection capability does not match the fortification criteria of its
defense against 200-year high tide level and 12-level wind and waves.
Shanghai needs to further strengthen the construction of sea dikeprojects and improve the tide-proof standards.

KEY WORDS: Yangtze Estuary, Extreme storm surge, Flood,
Sea dike, Numerical simulation, Sea level rise
INTRODUCTION
According to the forecast results of the 2020 China Sea Level Bulletinissued (Ministry of Natural Resources of the People's Republic of China,2020), the sea level along the Shanghai coast will rise by 50-180 mm in
the next 30 years. Based on the estimated results of global sea levelchanges and the water level data of more than 20 domestic tide gauge
stations, domestic scholars have given a forecast that the coastal sea
level of China will rise up to 20-60 cm by 2100 (Shen, 1998). Due tothe severe land subsidence in the Yangtze River Estuary, the relative sea
level rise rate in this region can be 5.44 mm/a, which is about threetimes the global sea level rise rate (Zhou, 2013). Based on the researchof the variation trend of Relative Sea Level Rise (RSLR) in Shanghai in2030, it is predicted that the RSLR in Pudong is about 8 mm/a, and theRSLR in Changxing and Hengsha Island is about 4-6 mm/a (Cheng,2015). Fig.1 shows the location map of Yangtze River Estuary, Pudong
New District, Changxing Island and Hengsha Island.

Fig.1 Location map of Yangtze River Estuary, Pudong New Area,Changxing Island and Hengsha Island.
Based on the full consideration of the nonlinear effects of storm surge
influencing factors (including sea level rise), this paper establishes a
two-dimensional storm surge flood calculation model integrating ocean
and land around Shanghai. Through this model, the flood control
capacity of the sea dike in the Yangtze Estuary region was
systematically studied under the background of sea level rise caused byclimate warming when the storm surge intensity increased. Storm surge
flooding risks under conditions of sea level rise, land subsidence, andsuperimposed super-standard extreme storm surge were assessed. Theseresearch results have very practical guiding significance for the designof sea dike engineering.

Due to the impact of sea level rise and land subsidence, the flood
control capability of the sea dike along the coast of Shanghai duringstorm surge needs to be further investigated. Based on a combination of
topographical changes and changes in land cover types, RSLR extends
storm surge inland. On the basis of RSLR phenomenon, numerous
scholars have carried out in-depth research on extreme storm surge,2734