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Effect of ice cover roughness on local scour around bridge piers
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  • Published: 14 January 2026

Effect of ice cover roughness on local scour around bridge piers

  • Shihao Dong1,
  • Zhenhua Zhang1,
  • Jun Wang1 &
  • …
  • Jueyi Sui2 

Scientific Reports , Article number:  (2026) Cite this article

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We are providing an unedited version of this manuscript to give early access to its findings. Before final publication, the manuscript will undergo further editing. Please note there may be errors present which affect the content, and all legal disclaimers apply.

Subjects

  • Engineering
  • Hydrology

Abstract

In cold-region rivers, the formation of ice cover during winter markedly modifies the hydraulic conditions, leading to enhanced local scour around in-stream infrastructures such as bridge piers. To analyze the flow characteristics and maximum local scour depth around the pier under both open-channel and ice-covered conditions with varying roughness, both experimental methods and numerical simulations were employed in this study. The findings reveal that, under rough ice-covered flow conditions, the interaction of elevated bed shear stress and intensified turbulent kinetic energy contributes to an increased maximum scour depth around the pier. Under identical approaching flow conditions, when the ratio of ice cover roughness to bed roughness increases to 1.9, the increase in maximum local scour depth around the pier becomes less pronounced owing to the enhanced energy dissipation caused by the rough ice cover. A numerical model for local scour around the pier under open-channel flow and ice-covered flow conditions was developed by integrating the RNG k − ε turbulence model with the Meyer-Peter sediment transport equation. A new formula was developed to estimate the maximum local scour depth around bridge piers considering various ice cover roughness conditions. Comparison with existing formulas demonstrates that the proposed formula achieves the highest accuracy, offering a useful reference for the design of bridge foundations in ice-affected regions.

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Data availability

The datasets used and/or analyzed during the current study are available from the corresponding author on request.

Abbreviations

B :

Flume width

B/D :

Flume width to pier diameter ratio

D :

Pier diameter

d 50 :

Median particle diameter

d s :

Maximum local scour depth

Fr :

Froude number

G :

Gravitational acceleration

H :

Approaching flow depth

k s :

Roughness coefficient

κ:

Von Kármán constan

n i :

Manning roughness coefficient of the ice cover

n b :

Manning roughness coefficient of the riverbed

n i/n b :

Ratio of ice cover roughness to riverbed roughness

ρ s :

Sand mass density

Q :

Flow rate

TKE:

Turbulent kinetic energy

\(\it \it {\text{u}}\text{*}\) :

Shear velocity

U :

Approaching flow velocity

U a :

Average velocity

U c :

Incipient sediment motion in open channel flow

U/U c :

Flow intensity

y :

Distance of the bottom ice cover surface

Z :

Distance from the riverbed

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Acknowledgements

The authors are grateful for the Joint Funds of the National Natural Science Foundation of China.

Funding

This study was supported by the Joint Funds of the National Natural Science Foundation of China (NSFC) under grant numbers U2443221 and U2243239.

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Authors and Affiliations

  1. School of Civil and Hydraulic Engineering, Hefei University of Technology, Hefei, 230009, China

    Shihao Dong, Zhenhua Zhang & Jun Wang

  2. School of Engineering, University of Northern British Columbia, 3333 University Way, Prince George, BCV2N4Z9, Canada

    Jueyi Sui

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Contributions

S.D.: laboratory works, data curation, formal analysis, methodology, and writing—original draft preparation; Z.Z.: conceptualization, laboratory supervision, and methodology; J.S.: conceptualization, methodology, and writing—review and editing; J.W.: conceptualization, laboratory supervision, methodology, and writing—review and editing.

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Correspondence to Jun Wang.

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Dong, S., Zhang, Z., Wang, J. et al. Effect of ice cover roughness on local scour around bridge piers. Sci Rep (2026). https://doi.org/10.1038/s41598-025-34352-1

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  • Received: 01 November 2025

  • Accepted: 28 December 2025

  • Published: 14 January 2026

  • DOI: https://doi.org/10.1038/s41598-025-34352-1

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Keywords

  • Ice cover roughness
  • Bridge pier
  • Local scour
  • Maximum scour depth
  • Turbulent kinetic energy
  • Numerical simulation
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