Author(s): Sriparna Paira; Subhasish Dey; Chanchal Kumar Mukherjee
Linked Author(s): Subhasish Dey
Keywords: Culvert; Scour; Maximum scour depth; Bed erosion
Abstract: The study deals with the characteristics of scour downstream of a culvert. The main objective is to study the scour characteristics including the influence of different parameters (tailwater depth, width of the culvert, sediment size, velocity of water through the culvert and drop height) on maximum scour depth. Dimensional analysis has been performed to get the maximum scour depth as a function of the considered parameter. From the experimental investigation it was found that with the increase of densimetric Froude number the maximum equilibrium scour depth increases. The variation of maximum scour depth with tailwater was sagging in nature and a nonlinear relationship exists between maximum scour depth and tailwater depth. On the other hand the variation of maximum scour depth with the grain size was hogging in nature and with an increase in grain size, the maximum scour depth decreases. In this study two polynomials were considered for the scour and dune profile. The expressions were developed to find the coefficients of these two polynomials from the boundary conditions. It was shown that the profiles computed from these equations (for 1 h and 10 h) have a satisfactory agreement with the experimental data. The volume per unit width of the scour hole and the sediment deposition as dune was expressed in terms of the polynomial equations and concluded that 16% of sediment by volume is washed out by the flow.
Year: 2018