An Experimental Study on the Effects of Debris Accumulation at the Culvert Inlet on Downstream Scour

Document Type : Regular Paper

Authors

1 Water Engineering Department, Faulty of Agriculture, Bu-Ali Sina University, Hamedan, Iran

2 Water engineering, Faculty of agriculture, Bu-Ali Sina university, Hamedan, Iran

Abstract

The major damage of hydraulic structures at river crossing occurs during floods and culverts is the structure which use as a part of drainage system in ephemeral streams. Failure in structures is caused for different reasons but pier and abutment scour is the main reason. The presence of debris causes larger scours and sediment removal compared to the absence of debris accumulation. In this study, the common problem of the flow blockage at culvert inlets is investigated applying a hydraulic model set in laboratory. Experiments were performed to understand the changes and interaction of scour depth over a range of downstream flow depths, ht and densimetric Froude number, Fo. The debris accumulation is modelled by rectangular plates of constant width (30 cm) and various heights (4, 8, 12, 16 cm) set at the culvert entrance. When culvert inlet area decreased by the smallest solid debris accumulation - which covered 20% of inlet area-, the upstream water level raised up to 12% and by the biggest solid debris size- which covered 80% of inlet area- water level increased up to 60%. Debris accumulation causes larger scours and sediment removal, so the scour hole area extended extremely in flow direction. A new maximum scour depth predictor equation has been proposed to predict the effects of debris accumulation at culvert inlet on downstream scour. This equation is well fitted with the experimental results of the current study and the results of experiments from the previous studies used to analyze presented formula.

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References

[1] Weeks, W. (2009) Australian Rainfall And Runoff Revision Project11: Blockage Of Hydraulic Structures. Engineers Australia.
[2] Hager, W. H., and Del Giudice, G. (1998) Generalized culvert design diagram. Journal of Irrigation and Drainage Engineering. ASCE, 124(5), 271–274.
[3] Johnson, P. A., Brown, E. R. (2000) Stream assessment for multicell culvert use. Journal of Hydraulic Engineering ASCE 126(5), 381–386.
[4] Chanson, H. 2004. Hydraulics of open channel flow. Elsevier.
[5] Norman, J.M., Houghtalen, R.J., Johnston, W.J. (2001) Hydraulic design of highway culverts. Hydraulic design series No. 5 (HDS-5), Federal Highway Administration .FHWA, Washington, D.C.
[6] Haffmans, G.J.C.M., Pilarczyk, K.W. (1995) Local Scour downstream of hydraulic structures. Journal of Hydraulic. Engineering, ASCE 121(4), 326-340.
[7] Liriano, S.L., Day, R.A., White, W.R. (2002) Scour at culvert outlets as influenced by the turbulent flow structure. Journal of Hydraulic Research, IAHR 40(3), 367–376.
[8] Abt, S.R., Ruff, J.F., Doehring, F.K. (1986) Culvert slope effects on outlet scour. Journal of Hydraulic Engineering, ASCE 111(10), 1363–1367.
[9] Abt, S.R., Ruff, J., Doehring, F., Donnell, C. (1987) Influence of culvert shape on outlet scour. Journal of Hydraulic Engineering, ASCE 113(3), 393–400.
[10] Zhang, R., & Wu, P. (2019). The investigation of shape factors in determining scour depth at culvert outlets. ISH Journal of Hydraulic Engineering, 1-7.
[11] Sarathi, P., Faruque, M.A.A., Balachandar, R. (2008) Influence of tailwater depth, sediment size and densimetric Froude number on scour by submerged square wall jets. Journal of Hydraulic Research IAHR 46(2), 158-175.
[12] Zhao, P., Yu, G., & Zhang, M. (2019). Local Scour on Noncohesive Beds by a Submerged Horizontal Circular Wall Jet. Journal of Hydraulic Engineering, 145(9), 06019012.
[13] Ade, F., Rajaratnam, N. (1998) Generalized Study of Erosion by Circular Horizontal Turbulent Jets. Journal of Hydraulic Research, IAHR 36(4), 613-635.
[14] Rigby, E. H., Boyd, M. J., Roso, S., Silveri, P., Davis, A. (2002) Causes and Effects of Culvert Blockage during Large Storms. Proc. 9th Int. Conf. on Urban Drainage, Portland, Oregon, USA, September 8-13.
[15] Ho, H. C. (2010) Investigation of unsteady and non-uniform flow and sediment transport characteristics at culvert sites. Phd Thesis.
[16] Ho, H.C., Muste, M., Ettema, R. (2013) Sediment self-cleaning multi-box culverts. Journal of Hydraulic Research, IAHR, 51(1), 92-101.
[17] Barthelmess, A.J., Rigby, E. (2011) Estimating culvert & bridge blockages – a simplified procedure. In Proceedings of the 34th World Congress of the International Association for Hydro-Environment Research and Engineering, A.C.T., Engineers Australia, Barton, Brisbane, Australia, pp. 39–47.
[18] Sorourian,S., Keshavarzi, A., Ball, J., Samali, B.(2014) Blockage Effects on Scouring Downstream of Box Culverts Under Unsteady Flow. Australian Journal of Water Resources, 18(2), 180-190.
[19] Sorourian, S., Keshavarzi, A., & Ball, J. E. (2015). Scour at partially blocked box-culverts under steady flow. In Proceedings of the Institution of Civil Engineers-Water Management 169(6), 247-259.
[20] Park, J. H., Sok, C., Park, C. K., and Do Kim, Y. (2016). A study on the effects of debris accumulation at sacrificial piles on bridge pier Scour: II. Empirical formula. KSCE Journal of Civil Engineering, 20(4), 1552-1557.
[21] De Dios, M., Bombardelli, F. A., Garcia, C. M., Liscia, S. O., Lopardo, R. A., Parravicini, J. A. (2016) Experimental characterization of three-dimensional flow vortical structures in submerged hydraulic jumps. Journal of Hydro-Environment Research.
[22] Day, R.S., Liriano, S.L, White, W.R. (2000) Effects of tailwater depth and model scale on scour at culvert outlets. . Proc. Inst. Civ. Eng. Marit. Eng. 48(3), 189-198.
[23] Emami, S., & Schleiss, A. J. (2010). Prediction of localized scour hole on natural mobile bed at culvert outlets. In Scour and Erosion. 844-853.
[24] Chiew, Y. M., & Lim, S. Y. (1996) Local scour by a deeply submerged horizontal circular jet. Journal of Hydraulic Engineering, ASCE, 122(9), 529-532.
[25] LIM, S.Y. (1995) Scour below unsubmerged full-flowing culvert outlets Proc. Inst. Civil Engineering in Water Management. 112(2), 136-149.

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History

  • Receive Date: 24 September 2019
  • Revise Date: 18 December 2019
  • Accept Date: 05 February 2020

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