Optimum Design of spur dikes dimension using multi-objective of harmony search algorithm, Case study: Zanjanrood River

One of the common methods of controlling the side erosion and rivers training is the use of spur dikes. It is important to consider several different and conflicting objectives in river engineering studies simultaneously. For this purpose, the optimum design of the dimensions of constructed spur dikes in Zanjanrood was considered with the aim of minimizing the cost and maximizing the sediment discharge. In the model, a combination of morphological model, design and optimization model of multi-objective harmony search algorithm were used and to evaluate the cross-section stability were used hypothetical theories. Calibration and validation of the model were performed by Zanjanrood data with Van Rijn sediment equation and Gill scouring equation. Sensitivity analysis of the model were performed for the parameters of discharge, slope and initial width of the river. By comparing different scenarios obtained from the Pareto front, better answers were provided than the plan implemented in Zanjanrood and the studies of other researchers. Finally, one of the points of the Pareto front must be selected for construction and execution. Choosing the right number depends on the designer's opinion and the existing priorities. in one of scenario that chosen as the optimal design, it has the lowest Euclidean distance compared to other scenarios with the ideal point. This scenario offers 244.58% lower cost and 25.48% more sediment discharge than Zanjanrood plan.