Morphological Evolution of the Scour Pit After Danjiangkou Dam Heightening Project

Ying Chen, Xian-zheng Wang, Hong-xia Zhang, Zhi-gang He

2022

Abstract

Danjiangkou Reservoir is the largest artificial fresh water lake in Asia, the water source of the middle route of the South-to-North Water Diversion Project. This paper analyzes the process and the reasons of the scour pit under Danjiangkou Dam,then particularly analyzes its morphological evolution after the Autumn flood in Hanjiang in 2021. After the flood in 2021, there are big increases in the range and depth of the scour pit. The results shows that the area of 75m contours of the spit increased from about 1.2×104 m2 to 1.4×104 m2. Correspondingly, sediment volume of the scour pit drastically decreased, especially the volume between the 75m and 60m contours. Furthermore, the Empirical Orthogonal Function (EOF) is applied to analyze the morphological evolution of the scour pit under the Danjiangkou dam. The topographic data are separated into independent spatial eigenfuntion along with temporal eigenfuntion by the EOF analysis. The first three modes provide a detailed, comprehensive description of the morphological evolution of the scour pit. The first mode accounts for 58.5% of the overall evolution patterns, it shows the trend of the scouring downstream of the scour spit. The second mode reflects that the scour pit achieved a dynamic balance of sediment. And the third mode indicates that the sediment source of the center of the scour pit. This paper explains that the EOF analysis can be used into the evolution of river-bed, and provides the theory basis for the safety operation of the Danjiangkou dam.

Paper Citation

in Harvard Style

Chen Y., Wang X., Zhang H. and He Z. (2022). Morphological Evolution of the Scour Pit After Danjiangkou Dam Heightening Project. In Proceedings of the 3rd International Symposium on Water, Ecology and Environment - Volume 1: ISWEE; ISBN 978-989-758-639-2, SciTePress, pages 308-318. DOI: 10.5220/0012024900003536

in Bibtex Style

@conference{iswee22,
author={Ying Chen and Xian-zheng Wang and Hong-xia Zhang and Zhi-gang He},
title={Morphological Evolution of the Scour Pit After Danjiangkou Dam Heightening Project},
booktitle={Proceedings of the 3rd International Symposium on Water, Ecology and Environment - Volume 1: ISWEE},
year={2022},
pages={308-318},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0012024900003536},
isbn={978-989-758-639-2},
}

in EndNote Style

TY - CONF

JO - Proceedings of the 3rd International Symposium on Water, Ecology and Environment - Volume 1: ISWEE
TI - Morphological Evolution of the Scour Pit After Danjiangkou Dam Heightening Project
SN - 978-989-758-639-2
AU - Chen Y.
AU - Wang X.
AU - Zhang H.
AU - He Z.
PY - 2022
SP - 308
EP - 318
DO - 10.5220/0012024900003536
PB - SciTePress