Scour around Spur Dike in Sand–Gravel Mixture Bed

Abstract

Scour is the main cause of failure for spur dike. The accurate prediction of scour around spur dike is essential to design a spur dike. The present study focuses on the maximum scour depth in equilibrium condition and parameters, which influence it in a sand–gravel mixture bed. Outcomes of the present experimental study showed that the non-dimensional maximum equilibrium scour depth increases with critical velocity ratio (U/Uca), water depth-armour particle ratio (h/da), Froude number for sediment mixture (Frsm), water depth-spur dike length ratio (h/l), and decreases with increase in armour particle-spur dike length ratio (da/l). The maximum scour depth is proportional to dimensionless parameters of U/Uca, h/da, Frsm, h/l, but the scour depth is inverse proportional to da/l. Scour around spur dike in a sand–gravel mixture is mainly influenced by the property of the sediment mixture. The scour increases with decrease in non-uniformity of the sediment mixture. A non-linear empirical equation is proposed to estimate the maximum scour depth at an upstream nose of rectangular spur dike with a maximum error of 15%. The sensitivity analysis indicates that the maximum non-dimensional equilibrium scour depth depends on Frsm, followed by the secondary sensible parameters da/l, h/l, and h/da.

Reduction of scour around circular piers using collars

“…River flooding is becoming more frequent with climate change, causing damage to hydraulics structures and bridge elements (Dhali et al, 2020; Singh et al, 2019). The natural hazards posed by the river systems depend on river flow characteristics and sediment transport in the river system (Pagliara & Kurdistani, 2015; Pandey, Lam, et al, 2019). This capacity is affected by the erosion and deposition of sediment that is finally determined by the stream bed level, the lowest elevation to which a stream can flow.…”

Pier Scour Prediction in Non-Uniform Gravel Beds

“…The relative sensitivity can be expressed as R.S. = (X × ∆Z)/(Z × ∆X) [36]. A linear sensitivity analysis was selected here, mainly because it is more understandable and computationally cheap while preserving true quantitative information about the linear influence of parameters.…”

Numerical investigation of flow field around T-shaped spur dyke in a reverse-meandering channel

“…The flow in a river bend or meandering channel is highly turbulent and stormy due to continuous change in curvature of banks and high topography irregularities (Pu et al 2020(Pu et al , 2021. The flow pattern in a curved channel consists of spiral flow between river bed and water surface, transverse rotational flow generated by the centrifugal force in bend, secondary flow, and so on (Pandey et al 2018a, 2018b, Singh et al 2019. It causes heavy bank erosion resulted in its lateral migration.…”

“…Despite its significant use, the study on spur dyke present in channel bend is still limited (Fazli et al 2008;Vaghefi et al 2019). The majority of studies in this field have been carried out in a straight channel such as Kothyari & Ranga Raju (2001), Jennifer et al (2011), Jiao et al (2017, Kuhnle & Alonso (2013), Pandey et al (2018aPandey et al ( , 2019Pandey et al ( , 2020Pandey et al ( , 2021, Pourshahbaz et al (2020), Singh et al (2020, Xiufang et al (2012) and so on. The flow past a spur dyke present at the channel bend or meander is highly turbulent, leading to the formation of local scour, which further increases with increasing scour depth.…”