Estimating of Scour in Downstream of the Water Level Regulation Structures

Document Type: Regular Paper


1 Assistant Professor, Faculty of Civil Engineering, Semnan University, Semnan, Iran

2 Young Researchers and Elite Club, Beyza Branch, Islamic Azad University, Beyza, Iran

3 Ph.D. Student, Faculty of Civil Engineering, Iran University of Science and Technology, Tehran, Iran


Scour in the downstream of hydraulic structures is a phenomenon which usually occurs due to exceeding the velocity or shear stress from a critical level. In this paper by using the laboratory data by Borman- Jouline and De-Agostino research, it was tried to get more accurate equations in order to calculate the maximum depth of scour in the downstream of the water level regulation structures. Comparing these equations with the results of the other researchers showed that these equations are much more accurate.  After that Artificial neural networks (ANNs) with learning algorithm of error back propagation (BP) were used to estimate maximum water scour depth, and the model which has seven neurons in its hidden layer was produced as the most appropriate model. Finally by using statistical parameters, the ANN model was compared with optimized equations. The results of this study showed high correlation between artificial neural network and proposed equation.


Main Subjects

[1] Rouse, H. )1940(.“Criteria for similarity in the transportation of sediment.Studies in engineering bull”., Univ. of Iowa, 20, 33–49.

[2] Doddiah, D., Albertson, M. L., and Thomas, R. (1953). “Scour from jets”. Proc., 5th Congr. Int. Assoc. for Hydraulic Res., Minneapolis, September, 161–169.

[3] D’Agostino, V. (1996). “La progett azionedell econtro briglie. Proc., 25th Convegno di Idraulica e Costruzion iIdrauliche”, Torino, September, 3, 107–118 (in Italian).

[4] Schoklitsch, A. (1932). “Kolk bildun gunter Ueberfall strahlen”. Wasser wirtschaft, 24, 341–343 (in German).

[5] Bormann, N. E., and Julien, P. Y. (1991). “Scour downstream of gradecontrol structures”. J. Hydraul. Eng., 117(5), 579–594.

[6] Mason, P. J., and Arumugam, K. (1985). “Free jet scour below dams and flip buckets”. J. Hydraul. Eng., 111(2), 220–235.

[7] D’Agostino, V., and Ferro, V. (2004). “Scour on Alluvial Bed Downstream of Grade-Control Structures. J. Hydraul. Eng., 130(1), 24–37.

[8] Jager, C. (1939). “Uber die AehnlichkeitbeiflussaulichenModellversuchen. Wasserkraft und Wasserwirtschaft.34(23/24), 269, (in German).

[9] Hartung, W. (1959). “Die Kolkbildung hinter U berstro¨mtenWeherenimHinblick auf eineBeweglichSturzbettgestaltung. Wasserwirtschaft, 49(1), 309–313 (in German).

[10] Chee, S. P., and Padiyar, P. V. (1969).  “Erosion at the base of flip buckets”. Eng. J., 52(111), 22–44.

[11] Chee, S. P., and Kung, T. (1974). “Piletas de derrubioautoformadas”. Proc., 6th Congr. Int. Assoc. for Hydraulic Res., Bogota, Columbia, Paper No. D.7, 1–11.

[12] Martins, R. (1975). “Scouring of rocky riverbeds and free-jet spillways”. Int. Water Power Dam Constr., 27(5), 152-153.

[13] Chee, S. P., and Yuen, E. M. (1985). “Erosion of unconsolidated gravel beds”. Can. J. Civ. Engrg., 12, 559-566.

[14] Yuen, E. M. (1984). “Clearwater scour by high velocity jets”.Thesis presented to the University of Windsor, at Windsor, Ontario, in partial fulfillment of the requirements for the degree of Master of Science.

[15] Akashi, N., and Saitou, T. (1986). ‘‘Influence of water surface on scour from vertical submerged jets.’’ J. Hydrosci. Hydr.Engrg., 55-69.

[16] Rajaratnam, N. (1981). “Erosion by plan turbulent jets”. J. Hydraul. Res., 19(4), 339–358.

[17] Albertson, M. L., Dai, Y. B., Jensen, R. A., and Rouse, H. (1950). ‘‘Diffusion of submerged jets”. Trans., ASCE, 115(2409), 639-697.

[18] Beltaos, S., and Rajaratnam, N. (1973). “Plane turbulent impinging jets”. J. Hydr. Res., 11(1), 29-59.

[19] Yuen, E. M. (1984). “Clearwater scour by high velocity jets”. Thesis presented to the University of Windsor, at Windsor, Ontario, in partial fulfillment of the requirements for the degree of Master of Science.

[20] Neill, C. R. (1968). “Note on initial movement of coarse uniform bed material”. J. Hydr. Res., 6(2), 173-176.

[21] Patterson, D. (1996). “Artificial Neural Networks: Theory and Applications. Singapore: Prentice Hall.

[22] Alborzi, M. (2000). “Introduction to Artificial Neural Networks”. Institute of Scientific Publications.