Estimating Scour Hole Dimensions of Ski Jump Downstream of Dams Using Granular Computing Model

Document Type : Research Article


1 M.Sc. Student of Environmental Engineering-Water Resources, Faculty of Environment, University of Tehran, Iran.

2 Assistant professor of Environmental Engineering, Faculty of Environment, University of Tehran, Iran.

3 M.Sc. Student, Surveying and Civil Engineering, College of Engineering, University of Tehran, Iran


Accurate estimation of scour parameters such as length, depth and width, have a major role in the management of this quite nonlinear phenomenon. The main goal of this study is to present a method based on granular computing model (GRC) to estimate scour parameters. For this purpose, scour hole of ski jumps downstream of dams (goal functions) were considered to be affected by hydraulic, morphological and geotechnical variables, and GRC model was used for calibration and verification of the phenomena. The implemented linear analysis showed that the goal functions are affected by flow rate variations, waterfall height and deposited particles average size, rather than lip angle. This fact was in compliance with the previous researches. The results also showed the GRC model results in predicting the goal functions had values very close to the measured ones, or with small discrepancies. More investigations showed that the GRC model was superior for estimation of scour depth of ski jumps downstream of dam to the well-known empirical formula proposed by other researchers.


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