Document Type : Original Article
Authors
1
Phd Student, Department of Water Sciences and Engineering, Ahv,C., Islamic Azad University, Ahvaz, Iran.
2
Department of Water Science Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz
3
Assistant Professor, Department of Water Sciences and Engineering, Ahv.C., Islamic Azad University, Ahvaz, Iran.
4
Professor. Department of Water Sciences and Engineering, Ahv.C., Islamic Azad University, Ahvaz, Iran.
5
Associate Professor, Department of Water Sciences and Engineering, Ahv,C., Islamic Azad University, Ahvaz, Iran.
10.22034/nawee.2026.586762.1239
Abstract
This study experimentally and numerically investigates the effectiveness of introducing slots into cylindrical bridge piers as a scour‑reduction countermeasure. Laboratory experiments were conducted under clear‑water conditions in a 15 m long rectangular flume. Four slot geometries—parallel, Y‑shaped, T‑shaped, and Sigma‑shaped—were examined to evaluate their influence on maximum scour depth and bed morphology. Three‑dimensional numerical simulations were performed using FLOW-3D. A mesh sensitivity analysis and turbulence model comparison were conducted to ensure numerical accuracy. Results showed that increasing mesh resolution significantly improved predictions, and the standard k-ε turbulence model with 1.7 million cells provided the best agreement with experimental data, with a relative error of about 8%. Comparative analysis revealed that slot geometry strongly influences flow structure and sediment transport. Among the tested configurations, the parallel slot achieved the greatest reduction in scour depth. The slot acts as a flow relief mechanism, allowing part of the incoming flow to pass through the pier body, thereby reducing stagnation pressure, weakening the horseshoe vortex system, and decreasing near‑bed shear stress. Overall, the results demonstrate that appropriately designed slots, particularly the parallel configuration, can effectively mitigate local scour and enhance the hydraulic performance and stability of bridge foundations
Keywords
Subjects
