Investigation of Local Scouring around Hydrodynamic and Circular Pile Groups under the Influence of River Material Harvesting Pits

Abstract

Mining activities can endanger the stability of hydraulic structures. Numerical modeling of local scouring around hydrodynamic and circular bridge pile groups, due to the action of clear water conditions via non-cohesive sediment, was performed using a computational fluid dynamics (CFD) model, a large eddy simulation (LES) turbulence model, and a van Rijn sedimentary model with FLOW-3D software. The pile groups were positioned upstream and downstream of a sand mining pit. The results showed that the scour depth around the downstream pile group was greater than that of the upstream one. Using hydrodynamic piers reduced the scour depth upstream of all piers and the material harvesting pit. The maximum reduction in scour depth was observed in front of the fifth pier, with a 29% reduction in scour depth. Additionally, for all models, as the material harvesting pit was moved downstream, the downstream turbulence was enhanced and stronger flow reversal and horseshoe vortices were detected in from of the downstream pile group. The flow patterns around the pile group showed that the presence of hydrodynamic piers in the upstream pile group leads to a decrease in the maximum flow velocity, whereas, when such piers were positioned in the downstream pile group, the velocity increases.

Turbulence structure and bank erosion process in a dredged channel

“…Sand extraction from riverbeds has become a thriving practice as it generates quick profit for the extracting party with low to no risk or harmful effect on the extracting party. The EIA study magnifies turbulence characteristics in the downstream flow (Barman, Kumar, & Sarma, 2018; Barman, Kumar, & Sarma, 2019a; Barman, Kumar, & Sarma, 2019b; Daneshfaraz et al, 2021; Lade, Deshpande, & Kumar, 2020; Neyshabouri, Farhadzadeh, & Amini, 2002, Padmalal & Maya, 2014). It aggravates the erosion/scouring of the river structures of interest (Lade & Kumar, 2020; Li, Wang, Ma, & Nie, 2020).…”

“…The riverbed material can be cohesive, non‐cohesive, or composite. All researchers have agreed that a cohesive riverbank has more strength than a non‐cohesive riverbank (Arai et al, 2018; Daneshfaraz et al, 2021; Roy, Barman, Das, Debnath, & Mazumder, 2020). Riverbank erosion causes loss of fertile lands but adds this as sediment load into the river.…”

“…The EIA study magnifies turbulence characteristics in the downstream flow (Barman, Kumar, & Sarma, 2018;Barman, Kumar, & Sarma, 2019a;Barman, Kumar, & Sarma, 2019b;Daneshfaraz et al, 2021;Lade, Deshpande, & Kumar, 2020;Neyshabouri, Farhadzadeh, & Amini, 2002, Padmalal & Maya, 2014. It aggravates the erosion/scouring of the river structures of interest Li, Wang, Ma, & Nie, 2020).…”

An inverse problem for modeling open channel flow with movable bed

“…The first is associated with the numerical solution procedure of the governing equations system. Alluvial flows on erodible beds are different from streams on a fixed bed, because the stream may remove sediments from the bed or, on the contrary, sediments carried by the stream may deposit on the bed, which usually leads to river bed degradation or aggradation (Liang & Marche 2009;Daneshfaraz et al 2021). It is supposed that the rate of bed morphological evolution has a lower order of magnitude compared to flow variations with low sediment concentrations (Estakhr et al 2022).…”

Stablity Analysis of roadbed under Flood Scouring

“…Campbell et al(2021) investigated the integrated geophysical technology for underwater detection of bridge foundation related scour and erodible scour filler. Daneshfaraz et al (2021) conducted numerical simulation of river scouring pile groups. Choudhary et al (2023) developed ANFIS-and GEP-based model for prediction of scour depth around bridge pier.…”