Experimental investigation of permeability and length of a series of spur dikes effects on the control of bank erosion in the meandering channel

Use of spur dikes by modifying the flow pattern is among the common methods for control of erosion at the river banks and their protection. In this research by construction of a laboratory meandering channel and use of five spur dikes, the effects of permeability and length of a series of spur dikes on the erosion control was investigated. The experiments were performed using three effective lengths, four permeability values and three Froude numbers in the non-submerged state. The results showed that the highest amount of bank retreat was achieved in impermeable spur dikes with a length of 9 cm and the lowest amount of bank retreat in permeable spur dike was 54% and a length of 15 cm. In this research use has been made of two criteria R2 and RMSE for comparing the data obtained from the predicted relationship and the observed data and showed a good compatibility.