Experimental and numerical investigation of scour around inclined pier group with sacrificial pile and collar

Document Type : Research Article


1 Tabriz University

2 Water Engineering Department, Faculty of Agriculture, University of Tabriz, Tabriz, Iran


The scour has been studied in hydraulic science for many years; due to its complexity, it has been the attention of hydraulic scientists. Hydraulic structures are situated as an obstacle in front of water flow that changed the flow pattern in their vicinity and causing the local scour around the structure. There are various methods to reduce local scour around the pier. In this research, sacrificial pile and collar were used to reduce the local scour around the inclined pier group. The results show that using the sacrificial pile in front of the inclined pier group, the effect of the inclined pier angle on the reduction of the scour is lower. So the difference between the percentage of scour reduction for the first and second inclined piers with the angle of 5 and 15 degrees is zero and in vertical pier is 1.4%. The use of three collars with a diameter of 4b in pier group with the distance of 4b between piers and presence of sacrificial pile in front of the first inclined pier in the distance of 3b compared to 2b show a greater scour depth reduction in front of the piers. In the numerical model, the use of an inclined pier group with the distance of 3b between piers and sacrificial pile with the distance of 2b shows lower turbulence intensity compared to distances of b and 3b.


Main Subjects

[1] H. Arvanaghi, A. Hosseinzadeh-Dalir, A. Fakherifard, Effect of side walls of the laboratory flume on scour depth around bridge piers, Journal of agricultural science, 16(2) (2006) 1-11. (In Persian)
[2] H. Arvanaghi, An experimental study of scour reduction around a bridge pier with rectangular collar and simulation of flow pattern around it by turbulence models. Thesis of PhD. Department of Water Engineering, Tabriz University, Iran, 2009. (In Persian)
[3] B. Ataie-Ashtiani, A. Beheshti, Experimental investigation of clear-water local scour at pile groups, Journal of Hydraulic Engineering, 132(10) (2006) 1100-1104.
[4] Y. Aghaee-Shalmani, H. Hakimzadeh, Experimental investigation of scour around semi-conical piers under steady current action, European Journal of Environmental and Civil Engineering, 19(6) (2015) 717-732.
[5] B. Ataie-Ashtiani, A. Aslani-Kordkandi, Flow field around single and tandem piers, Flow, turbulence and combustion, 90(3) (2013) 471-490.
[6] N. Azam, M. Ghomeshi, Influence of sacrificial piles on scour reduction of cylindrical bridge pier, Journal of water and soil sience, 23(3) (2013) 123-134. (In Persian)
[7] Z. Bozkus, M. Çeşme, Reduction of scouring depth by using inclined piers, Canadian Journal of Civil Engineering, 37(12) (2010) 1621-1630.
[8] Z. Bozkus, O. Yildiz, Effects of inclination of bridge piers on scouring depth, Journal of Hydraulic Engineering, 130(8) (2004) 827-832.
[9] W.-Y. Chang, J.-S. Lai, C.-L. Yen, Evolution of scour depth at circular bridge piers, Journal of Hydraulic Engineering, 130(9) (2004) 905-913.
[10] Y. Chiew, B. Melville, Local scour around bridge piers, Journal of Hydraulic Research, 25(1) (1987) 15-26.
[11] A. Fluent, ANSYS fluent theory guide 15.0, ANSYS, Canonsburg, PA,  (2013).
[12] S.S. Hosseini, M. Esmaeili Varaki, R. Fazleola, Experimental investigation of scour around inclined bridge piers group based on piles group, Journal of water and soil science, 26(4/2) (2016) 135-147. (In Persian)
[13] V. Kumar, K.G.R. Raju, N. Vittal, Reduction of local scour around bridge piers using slots and collars, Journal of hydraulic engineering, 125(12) (1999) 1302-1305.
[14] A. Kassem, Three-dimensional model analusis of pier scour hydraulics: a supplement to experimental and field investigations. World Environmental and Water Resource Congress, (2006) May 21-25, Omaha, Nebraska, United States.
[15] B. Mahjoob, B. Mohammadnezhad, J. Behmanesh, Numerical modeling of local scouring around group bridge piers and compared with experimental results, Journal of water and soil, 28(2) (2014) 267-275.
[16] B.W. Melville, Y.-M. Chiew, Time scale for local scour at bridge piers, Journal of Hydraulic Engineering, 125(1) (1999) 59-65.
[17] B.W. Melville, A.C. Hadfield, Use of sacrificial piles as pier scour countermeasures, Journal of Hydraulic Engineering, 125(11) (1999) 1221-1224.
[18] B.W. Melville, Pier and abutment scour: integrated approach, Journal of hydraulic Engineering, 123(2) (1997) 125-136.
[19] S.A.H. Mahmoudi, M. Heidar Pour, Evaluate the performance of the control and reduction of scour protection of bridge piers cylindrical candles, Journal of engineering & construction management, 1(3) (2016) 7-11. (In Persian)
[20] A.J. Raudkivi, R. Ettema, Clear-water scour at cylindrical piers, Journal of Hydraulic Engineering, 109(3) (1983) 338-350.
[21] M. Vaghefi, M. Ghodsian, S. Salimi, The effect of circular bridge piers with different inclination angles toward downstream on scour, Sadhana, 41(1) (2016) 75-86.
[22] C. Wang, F. Liang, X. Yu, Experimental and numerical investigations on the performance of sacrificial piles in reducing local scour around pile groups, Natural Hazards, 85(3) (2017) 1417-1435.
[23] W. Xiong, C.S. Cai, B. Kong, X. Kong, Cfd simulations and analyses for bridga-scour development using a dynamic-mesh updating technique, Journal of computing in civil engineering, 30(1) (2014) 1-11.
[24] A.R. Zarrati, M.R. Chamani, A. Shafaie, M. Latifi, Scour countermeasures for cylindrical piers using riprap and combination of collar and riprap, International Journal of Sediment Research, 25(3) (2010) 313-322.
[25] A. Zarrati, M. Nazariha, M. Mashahir, Reduction of local scour in the vicinity of bridge pier groups using collars and riprap, Journal of Hydraulic Engineering, 132(2) (2006) 154-162.