Experimental investigation of the effect of series length of T-shaped spur dikes on the control of bank erosion in non-submerged conditions in the meandering channel

The use of spur dikes is one of the most common methods for controlling bank erosion and protecting river shores. In fact, the presence of the spur dikes causes the modification of hydraulic flow conditions as well as the reduction of water erosion power at the distance of two spur dike, that eventually causes the sedimentation and stabilization of the river banks. In this study, we investigated the effect of T-shaped spur dikes on erosion control by constructing a laboratory channel of meandering and using five spur dike. The experiments were conducted by taking three effective lengths three different froude numbers in impermeable and non-submerged conditions. The results of this study indicate that with the increase of the length of the spur dikes, the retreat rate has decreased. For the length of 9, 12 and 15 cm respectively, about 31.7, 35.4 and 58.0 percent of the mean retreat of the bank compared to the state without the spur dike decreased. In this study, three criteria R2, RMSE and MAE were used to compare the data obtained from the formula and the laboratory data, the amount of these indices were estimated 0.924, 0.127 and 0.097, respectively.