Al-Rafidain Engineering Journal (AREJ)

The Effect of the Piles Cap Elevation on Local Scour around Complex Bridge Piers

Document Type : Research Paper

Authors

Dams and Water Resources Engineering Department, College of Engineering, University of Mosul, Mosul, Iraq

Abstract

Bridges are built to facilitate transportation between the two banks of the rivers and waterways. They are usually supported by piers with geometric shapes that differ from one bridge to another, such as a complex pier. Due to the intersection between bridge piers and water flow, many water vortices are generated, causing local scour around the bridge piers. Local scour around the complex piers is affected by many factors, including the geometry of the piers and other hydraulic factors. In this study, a number of laboratory experiments were conducted to investigate the effect of the pile cap elevation and water depth on local scour around complex pier piers using materials with a regular gradient and under the condition of sediment-free water flow. Eight ratios of the pile cap  elevation to the cap thickness Z/Tpc were studied, ranging from -32% to 50%, and six different flow depths (y) between 10.5 cm and 18 cm. The results showed that the maximum scour depth was recorded to be 10.8 cm when the pile cap was partially covered with a sand bed (Z/TPC = 50%), the depth of scour increased with the increase in water depth up to 13.5 cm, then the effect of the increase in water depth was slight, although Increasing the intensity of the vortices due to the presence of the piles covering that prevent the impact of these vortices from reaching the soil surface.

Keywords

Main Subjects

References
  1. M. I. Alsaidi, G. A. A.-M. Hayawi, and M. A. Alsawaf, “Study of Scour Around Cylindrical Bridge Piers with Circular Openings,” Al-Rafidain Eng. J., vol. 25, no. 2, pp. 66–74, 2020.
  2. S. A. Hosseini, M. Osroush, A. A. Kamanbedast, and A. Khosrojerrdi, “The effect of slot dimensions and its vertical and horizontal position on the scour around bridge abutments with vertical walls,” Sādhanā, vol. 45, no. 1, pp. 1–16, 2020.
  3. C. Grimaldi, R. Gaudio, F. Calomino, and A. H. Cardoso, “Countermeasures against local scouring at bridge piers: slot and combined system of slot and bed sill,” J. Hydraul. Eng., vol. 135, no. 5, pp. 425–431, 2009.
  4. E. Sanadgol, M. Heidarpour, and R. Mohammadpour, “Reduction of local scouring at round-nosed rectangular piers using a downstream bed sill,” J. South african Inst. Civ. Eng., vol. 63, no. 3, pp. 62–70, 2021.
  5. M. Esmaeili Varaki, N. Tavazo, and A. Radice, “Using a Bed Sill as a Countermeasure for Clear-Water Scour at a Complex Pier with Inclined Columns Footed on Capped Piles,” Hydrology, vol. 9, no. 4, p. 65, 2022.
  6. A. Y. Abdulhafedh, N. K. Alomari, and A. M. S. Al-Janabi, “Scour hole reduction at a diversion channel junction using different entrance edge shapes,” Int. J. Sediment Res., 2023.
  7. A. AA Alkatan, M. YM Aljubori, and B. MA Noori, “Laboratory comparison study of scour downstream weirs and communed gates,” Al-Rafidain Eng. J., vol. 17, no. 5, pp. 60–75, 2009.
  8. I. A. I. Al-Hafith and B. M. A. Noori, “Laboratory Study Of Scour Downstream Gabions Protecting Rockfill Weirs,” Al-Rafidain Eng. J., vol. 15, no. 4, pp. 1–15, 2007.
  9. N. K. Alomari, B. Yusuf, T. A. Mohammad, and A. H. Ghazali, “Experimental investigation of scour at a channel junctions of different diversion angles and bed width ratios,” Catena, vol. 166, pp. 10–20, 2018.
  10. N. K. Alomari, P. Sihag, A. M. Sami Al-Janabi, and B. Yusuf, “Modeling of scour depth and length of diversion channel flow system with soft computing techniques,” Water Supply, 2023.
  11. L. J. Prendergast and K. Gavin, “A review of bridge scour monitoring techniques,” J. Rock Mech. Geotech. Eng., vol. 6, no. 2, pp. 138–149, 2014.
  12. M. Safar Alyas Michael Al-Saffar and K. S. Al-Shaikh-Ali, “Riprap Gradation Effect On Local Scour Around Bridge Piers,” Al-Rafidain Eng. J., vol. 16, no. 1, pp. 56–68, 2008.
  13. S. Ata Amini, T. A. Mohammad, A. A. Aziz, A. H. Ghazali, and B. B. K. Huat, “A local scour prediction method for pile caps in complex piers,” in Proceedings of the Institution of Civil Engineers-Water Management, 2011, vol. 164, no. 2, pp. 73–80.
  14. A. A. Beheshti and B. Ataie-Ashtiani, “Experimental study of three-dimensional flow field around a complex bridge pier,” J. Eng. Mech., vol. 136, no. 2, pp. 143–154, 2010.
  15. B. Ataie-Ashtiani, Z. Baratian-Ghorghi, and A. A. Beheshti, “Experimental investigation of clear-water local scour of compound piers,” J. Hydraul. Eng., vol. 136, no. 6, pp. 343–351, 2010.
  16. A. Amini, B. W. Melville, T. M. Ali, and A. H. Ghazali, “Clear-water local scour around pile groups in shallow-water flow,” J. Hydraul. Eng., vol. 138, no. 2, pp. 177–185, 2012.
  17. D. Ferraro, A. Tafarojnoruz, R. Gaudio, and A. H. Cardoso, “Effects of pile cap thickness on the maximum scour depth at a complex pier,” J. Hydraul. Eng., vol. 139, no. 5, pp. 482–491, 2013.
  18. A. Amini, B. W. Melville, and T. M. Ali, “Local scour at piled bridge piers including an examination of the superposition method,” Can. J. Civ. Eng., vol. 41, no. 5, pp. 461–471, 2014.
  19. M. Moreno, A. Muralha, L. Couto, R. Maia, and A. H. Cardoso, “Influence of column width on the equilibrium scour depth at a complex pier,” in Proceedings of 36th IAHR World Congress, The Hague, The Netherlands, 2015, vol. 28.
  20. M. Moreno, R. Maia, and L. Couto, “Effects of relative column width and pile-cap elevation on local scour depth around complex piers,” J. Hydraul. Eng., vol. 142, no. 2, p. 4015051, 2016.
  21. Y. Yang, B. W. Melville, D. M. Sheppard, and A. Y. Shamseldin, “Clear-water local scour at skewed complex bridge piers,” J. Hydraul. Eng., vol. 144, no. 6, p. 4018019, 2018.
  22. D. A. Baghbadorani, B. Ataie-Ashtiani, A. Beheshti, M. Hadjzaman, and M. Jamali, “Prediction of current-induced local scour around complex piers: Review, revisit, and integration,” Coast. Eng., vol. 133, pp. 43–58, 2018.
  23. Y. Yang, M. Qi, X. Wang, and J. Li, “Experimental study of scour around pile groups in steady flows,” Ocean Eng., vol. 195, p. 106651, 2020.
  24. D. M. Sheppard, B. Melville, and Y. Yang, “Local Equilibrium Sediment Scour Prediction at Bridge Piers with Complex Geometries,” J. Hydraul. Eng., vol. 149, no. 4, p. 4023003, 2023.
  25. [25]       F. Martinez, P. Winckler, L. Zamorano, and F. Landeta, “Bridge Pier Scour in Complex Environments: The Case of Chacao Channel in Chile,” Water, vol. 15, no. 2, p. 296, 2023.
  26. A. Y. Abdalhafedh and N. K. Alomari, “The effect of entrance edges shape of the diversion channel on the dividing streamlines behavior at the junction region,” Al-Rafidain Eng. J., vol. 26, no. 2, pp. 218–226, 2021.
  27. B. W. Melville, “Pier and abutment scour: integrated approach,” J. Hydraul. Eng., vol. 123, no. 2, pp. 125–136, 1997.
  28. N. MOHAMMED, “Modelling water and sediment flow in branching channel system.” Doctoral dissertation, Universiti Putra Malaysia, 2017.
Al-Rafidain Engineering Journal (AREJ)
Volume 28, Issue 2
September 2023
Page 199-208
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