مشخصات پژوهش

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.