Hostname: page-component-78c5997874-s2hrs Total loading time: 0 Render date: 2024-11-17T04:20:52.528Z Has data issue: false hasContentIssue false
  • English
  • Français

On the Flow Structures Under a Partially Inundated Bridge Deck

Published online by Cambridge University Press:  22 March 2012

C. Lin ,
M.-J. Kao ,
S.-C. Hsieh ,
L.-F. Lo  and
R. V. Raikar
C. Lin*
Affiliation:
Department of Civil Engineering, National Chung Hsing University, Taichung, Taiwan 40227, R.O.C.
M.-J. Kao
Affiliation:
Department of Civil Engineering, National Chung Hsing University, Taichung, Taiwan 40227, R.O.C.
S.-C. Hsieh
Affiliation:
Department of Civil Engineering, National Chung Hsing University, Taichung, Taiwan 40227, R.O.C.
L.-F. Lo
Affiliation:
Department of Civil Engineering, National Chung Hsing University, Taichung, Taiwan 40227, R.O.C.
R. V. Raikar
Affiliation:
Department of Civil Engineering, K. L. E. S. College of Engineering and Technology, Belgaum 590008, India
*
*Corresponding author ([email protected])
Get access

Abstract

This paper presents the flow structure under a partially inundated bridge deck measured by using particle image velocimetry (PIV) and flow visualization techniques. The approaching flow was subcritical having Froude number F in the range 0.12 ∼ 0.55. The proximity ratio Pr (= ratio of clearance below the bridge deck h to the total depth of deck D) was varied from 0.57 to 2. Depending upon the Froude number F and proximity ratio Pr, four types of flow structures under the bridge deck were recognized. In flow Type I, the water surface elevation on the downstream side of bridge deck is slightly lower than the counterpart on the upstream side, and the shear layer formed at the bottom of upstream girder continuously fluctuates and touches soffit of all girders. In the case of flow Type II, the water surface on downstream side of bridge deck is lower than that on the upstream side and the shear layer originating from the upstream girder impinges near the third cavity between girders. However, in both the cases, the cavities between the girders are completely occupied by vortices. On the contrary, in the cases of flow Type III and flow Type IV, the flow is separated from the upstream girder edge. However, in flow Type III, the separated flow impinges on successive girders and cavities are partially filled by water; while in flow Type IV, the flow is totally separated from the deck bottom like orifice flow. The phenomena of vortex formation within the cavities are discussed for the cases of flow Type I and flow Type II. Also, for the vertical distribution of mean streamwise velocity in the shear layer below bridge deck, the nonlinear regression equations are developed. Using the distributions of measured mean streamwise velocity within the shear layer below the bridge deck at different streamwise distances, the similarity profile is obtained. The mean velocity deficit (usl – usu) and representative thickness bs are considered as the appropriate characteristic velocity and length scales for developing similarity profile. The proposed characteristic scales provided unique similarity profiles having promising regression coefficient. The similarity profile proposed is suitable for more general case of bridge deck having different bridge girders and even for rectangular block without girder. Further, the turbulence characteristics for the flow below the bridge deck are also presented.

Keywords

BridgesPressured flowInundated flowFlow visualizationParticle image velocimetryShear layerSimilarity profileTurbulence
Type
Articles
Information
Journal of Mechanics , Volume 28 , Issue 1 , March 2012 , pp. 191 - 207
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2012

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Breusers, H. N. C., Nicollet, G. and Shen, H. W., “Local Scour Around Cylindrical Piers,” Journal of Hydraulic Research, 15, pp. 211–252 (1977).CrossRefGoogle Scholar
2. Breusers, H. N. C. and Raudkivi, A. J., Scouring, IAHR Hydraulic Structures Design Manual, 2, A. A. Balkema, Rotterdam, The Netherlands (1991).Google Scholar
3. Dey, S., “Local Scour at Piers, Part I: A Review of Development of Research,” International Journal for Sediment Research, 12, pp. 23–46 (1997).Google Scholar
4. Melville, B. W. and Coleman, S. E., Bridge Scour, Water Resources Publications, Fort Collins, Colorado (2000).Google Scholar
5. Richardson, E. V. and Davis, S. R., Evaluating Scour at Bridges, HEC18 FHWA NHI-001, Federal Highway Administration, US Department of Transportation, Washington, DC (2001).Google Scholar
6. Naudascher, E. and Medlarz, H. J., “Hydrodynamic Loading and Backwater Effect on Partially Submerged Bridges,” Journal of Hydraulic Research, 21, pp. 213–232 (1983).CrossRefGoogle Scholar
7. Umbrell, E. R., Young, G. K., Stein, S. M. and Jones, J. S., “Clear-Water Contraction Scour Under Bridges in Pressure Flow, Journal of Hydraulic Engineering, 124, pp. 236–240 (1998).CrossRefGoogle Scholar
8. Jempson, M. A., “Flood and Debris Loads on Bridges,” Ph.D. Thesis, Department of Civil Engineering, University of Queensland, St. Lucia (2000).Google Scholar
9. Picek, T., Havlik, A., Mattas, D. and Mares, K., “Hydraulic Calculation of Bridges at High Water Stages,” Journal of Hydraulic Research, 45, pp. 400–406 (2007).CrossRefGoogle Scholar
10. Abed, L. M., “Local Scour Around Bridge Piers in Pressure Flow, Ph.D. Thesis, Department of Civil Engineering, Colorado State University, Fort Collins, Colorado (1991).Google Scholar
11. Arneson, L. A. and Abt, S. R., “Vertical Contraction Scour at Bridges with Water Flowing Under Pressure Conditions,” Transportation Research Record, 1647, pp. 10–17 (1999).CrossRefGoogle Scholar
12. Verma, D. V. S., Setia, B. and Bhatia, U., “Constriction Scour in Pressurized Flow Condition,” International Journal of Engineering Transaction B: Applications, 17, pp. 237–246 (2004).Google Scholar
13. Lyn, D. A., “Pressure-Flow Scour: A Reexamination of the HEC-18 Equation,” Journal of Hydraulic Engineering, 134, pp. 1015–1020 (2008).CrossRefGoogle Scholar
14. Junke, G., Kornel, K., Jorge, P. O. and Kevin, F., “Bridge Pressure Flow Scour at Clear Water Threshold Condition,” Transaction of Tianjin University, 15, pp. 79–94 (2009).Google Scholar
15. Malavasi, S. and Blois, G., “Influence of the Free Surface on the Flow Pattern Around a Rectangular Cylinder,” Proceedings of FLUCOME 2007— The Ninth International Symposium on Fluid Control, Measurement and Visualization, September 16-19, Tallahassee, Florida (2007).Google Scholar
16. Lo, L. F., “Study on the Characteristics of Flow Field Under a Partially Inundated Bridge Deck,” Master Thesis, National Chung Hsing University, Taiwan (2010).Google Scholar
17. Lin, C., Hwung, W. Y., Hsieh, S. C. and Chang, K. A., “Reply to the Discussion: Experimental Study on Mean Velocity Characteristics of Flow over Vertical Drop,” Journal of Hydraulic Research, 46, pp. 425–428 (2008).Google Scholar
18. Lin, W. J., Lin, C, Hsieh, S. C., Li, C. C. and Raikar, R. V., “Characteristics of Shear Layer Structure in Skimming Flow over a Vertical Drop Pool,” Journal of Engineering Mechanics, 135, pp. 1452–1466 (2009).CrossRefGoogle Scholar
19. Soldati, A. and Monti, R., Turbulence Structure and Modulation, Springer-Verlag, New York (2001).CrossRefGoogle Scholar