An Optimal Design for Dimensions of Water Diversion System in Dams using and Analyzing Hydraulic Uncertainties and Hydrologic Risk

Document Type : Research Article


1 Professor, School of Civil Engineering, University of Tehran, Tehran, Iran

2 M.Sc, Engineering Department, Islamic Azad University Science & Research Branch , Tehran, Iran

3 Assistant Professor, Technical and Engineering Campus of Shahid Beheshti University


Designing water diversion system has been a challenge for dam designers due to its much work as well as heavy costs. The transit capacity of diversion systems and the method by which a dam should be designed would be studied by scholars. In this study, a model is introduced for optimizing the dam water diversion system through two approaches. The first approach is conducted by the same principles of consulting plan as well as the optimization methods for optimal diversion system. In the second approach, with an eye to the uncertainties of hydraulic parameters and hydrological risk analysis, a numerical model is presented based on the initial costs of the project, the failure costs and the general risk of the system. Next, in both approaches, employing an optimal genetic algorithm and a suitable cost function which includes the cost of building the diversion system, dam and the cost of system damage due to the flood, the most appropriate diameter, level, the cover material, the length of tunnels and the height of upstream cofferdam and the height of downstream cofferdam will be determined. It is also determined whether the upstream cofferdam should have overflow. In this study, the Karoun Dam 4 in southwest of Iran is selected as the case study. The characteristics of the consultant plan for the height of upstream cofferdam, height of downstream cofferdam, and the tunnel diameters are 40, 20, 9.5, and 9.5 meters respectively. The results indicated that height of upstream cofferdam, height of downstream cofferdam, the tunnel diameters are 38,16,9.5 and 9.5 meters respectively for the first approach. They are 33, 5, 9, and 9 meters for the second approach. Thereby, the second model has the lowest annual expected cost compared with that of the consultant plan. 


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  • Receive Date: 29 September 2015
  • Revise Date: 23 July 2016
  • Accept Date: 30 August 2016
  • First Publish Date: 30 August 2016