Title: Modelling of scour depth in the existing bridge piers with and without an adjacent parallel bridge

Authors: Biswajit Dalal; Subhrajyoti Deb

Addresses: Department of Civil Engineering, ICFAI University Tripura, Mohanpur-799210, Tripura, India ' Department of Civil Engineering, ICFAI University Tripura, Mohanpur-799210, Tripura, India

Abstract: This paper presents a hydraulic simulation conducted to assess the stability of the 'Netaji Subhas Bridge' on the Gomti River in Tripura. The simulation takes into account different scour profiles and numerous flood events. The calculation of local scour at various piers takes into account four different flow profiles: PF1 (1,495 m³/s), PF2 (1,147 m³/s), PF3 (711 m³/s) and PF4 (475 m³/s). The analysis of the HEC-RAS model reveals that the scour depth (Y_s) and the Froude's number (F_r) exhibit a decrease for all flow profiles when a parallel bridge is constructed upstream of the existing bridge. However, if the new bridge is constructed on the downstream side, then Y_s and Fr are increased for PF2, PF3 and PF4, but in the case of PF1, only the Y_s decreased. Therefore, the safer and more serviceable option is to construct the parallel bridge on the upstream side of the existing bridge.

Keywords: Gomti River; parallel bridges; HEC-RAS; modelling; scour depth.

DOI: 10.1504/IJHST.2025.144239

International Journal of Hydrology Science and Technology, 2025 Vol.19 No.2, pp.152 - 169

Received: 22 Aug 2023
Accepted: 08 Dec 2023
Published online: 03 Feb 2025 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article