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Abstract
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Local scouring around sloped bridge piers in steady currents was studied both experimentally and
mathematically. The effects of different inclination angles, flow intensities, flow depths, and pier size on local
scouring were investigated. The experimental results show that the scouring depth increases with an increase in
the values of discharge and pier width. The scouring depth for the sloped piers is smaller than the vertical piers
one and the maximum scouring depth continuously decreases as the pier inclination angle increases. Prediction
of the scouring depth around bridge piers using analytical models can be utilized in the feasibility studies of
different models, and evaluations of the parametric analytical. Therefore, it was tried to model the scouring
depth as a function of Froude number, flow intensity, and relative roughness parameters using non-dimensional
analysis. The regression analysis based models were introduced to determine the scouring depth at upstream side
of the pier using experimental tests data. Step-wise linear regression showed that the value of relative scouring
depth has considerably good correlation only with two non-dimensionless parameters of inclination angle and
normalized approaching flow depth. In this regard, some linear and nonlinear regression tools were utilized to
establish functional relationships between these variables. Statistical indices and residual analyses of the models
revealed the suitability of the models. Comparison of the experimental and predicted value of relative scouring
depth illustrates that the suggested models can reasonably predict this parameter.
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