Clear Water Scour at Circular Piers: a Model
Publication: Journal of Hydraulic Engineering
Volume 121, Issue 12
Abstract
The three-dimensional quasi-steady vortex flow field around circular piers in a quasi-equilibrium scour hole under a clear water regime has been investigated experimentally. The main characteristic features of the flow, to be modeled, are a relatively large secondary vortex flow within the scour hole and skewed velocity distributions along the circumference of the pier. The flow field has been divided into a number of parts according to the flow characteristics. The components of quasi-steady velocity for different parts have been theoretically expressed in the form of equations satisfying the continuity equation and the requirements of fitting an individual profile of the measured velocity components. Using the suitable functions, the equations of the velocity components derived for different parts have been combined and matched at the junctions of these parts to get a single equation for each velocity component. The measured data have been utilized to determine the coefficients and exponents used in these equations through curve fittings. The proposed flow model, which corresponds closely with the observations, can be utilized to simulate the flow field in prototype.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Breusers, H. N. C., Nicollet, G., and Shen, H. W.(1977). “Local scour around cylindrical piers.”J. Hydr. Res., 15(3), 211–252.
2.
Dargahi, B. (1982). “Local scouring around bridge piers—a review of practice and theory.”Bull. No. TRITA-VBT-114, Royal Inst. of Technol., Hydr. Lab., Stockholm, Sweden.
3.
Dargahi, B. (1987). “Flow field and local scouring around a cylinder.”Bull. No. TRITA-VBI-137, Royal Inst. of Technol., Hydr. Lab., Stockholm, Sweden.
4.
Dargahi, B.(1989). “The turbulent flow field around a circular cylinder.”Experiments in Fluids, 8, 1–12.
5.
Dargahi, B.(1990). “Controlling mechanism of local scouring.”J. Hydr. Engrg., ASCE, 116(10), 1197–1214.
6.
Dey, S. (1991). “Clear water scour around circular bridge piers: A model,” PhD thesis, Indian Inst. of Technol., Kharagpur, India.
7.
Dey, S. (1994a). “Bed shear in equilibrium scour at a circular pier.”Proc., Nat. Symp. on Recent Trends in Design of Hydr. Struct., Roorkee, India, 293–300.
8.
Dey, S. (1994b). “Bed shear in evolving scour around a circular pier.”Proc., 9th Congr. of Asian and Pacific Div. of IAHR, Singapore.
9.
Dey, S., and Bose, S. K.(1994). “Bed shear in equilibrium scour around a circular cylinder embedded in a loose bed.”Appl. Math Modelling, 18(5), 265–273.
10.
Dey, S., Bose, S. K., and Sastry, G. L. N. (1992a). “Clear water scour at circular piers, part I: Flow model.”Proc., 8th Congr. of Asian and Pacific Div. of IAHR, Pune, India, III(C), 69–80.
11.
Dey, S., Bose, S. K., and Sastry, G. L. N. (1992b). “Clear water scour at circular piers, part II: Design formula.”Proc., 8th Congr. of Asian and Pacific Div. of IAHR, Pune, India, III(C), 81–92.
12.
Ettema, R. (1980). “Scour at bridge piers.”Rep. No. 216, Univ. of Auckland, Auckland, New Zealand.
13.
Hjorth, P. (1975). “Studies on the nature of local scour.”Bull. series A No. 46, Dept. of Water Resour. Engrg., Univ. of Lund, Sweden.
14.
Maskell, E. G. (1955). “Flow separation in three-dimensions.”Rep. No. Aero 2565, Royal Aircraft Establishment, Faranborough.
15.
Melville, B. W. (1975). “Local scour at bridge sites.”Rep. No. 117, Univ. of Auckland, Auckland, New Zealand.
16.
Odgaard, A. J.(1989). “River-meander model. I: development.”J. Hydr. Engrg., ASCE, 115(11), 1433–1450.
17.
Raudkivi, A. J.(1986). “Functional trends of scour at bridge piers.”J. Hydr. Engrg., ASCE, 112(1), 1–13.
18.
Rozovksii, I. L. (1961). Flow of water in bends of open channels. Israel Program for Scientific Translations, Jerusalem, Israel.
19.
Tingsanchali, T., and Maheswaran, S.(1990). “2-D depth-averaged flow computation near groyne.”J. Hydr. Engrg., ASCE, 116(1), 71–86.
Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 121 • Issue 12 • December 1995
Pages: 869 - 876
Copyright
Copyright © 1995 American Society of Civil Engineers.
History
Published online: Dec 1, 1995
Published in print: Dec 1995
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.