Placing the bridge piers in the river with a convergent bend can make the flow and erosion pattern complicated around the bridge piers. In this research, the maximum depth and volume of scour hole around piers were investigated in convergent bends of a river. The experimental model with a 90° convergent bend was made with a central curvature radius of 170 cm. The piers with the cylindrical and cubic shapes with different dimensions were prepared and installed at different positions of 90° convergent bend to investigate the scouring condition under three flow discharges in Clear-water mode. On the other hand, natural sand with uniform grain size of d₅₀ = 1 mm was used as the bed materials. The results revealed that depth and volume of the scour hole around piers increase with increasing angle, so that the maximum depth and volume of the scour hole occurred at the angle 75°. Furthermore, the depth and volume of the scour hole around cylindrical piers were lower than cubic piers in all cases. Also, the scour hole shape was asymmetric relative to central axis of the channel and was mainly the extension of the hole towards the inner bend.

将桥墩以会聚弯曲的方式放置在河流中会使桥墩周围的水流和侵蚀模式变得复杂。在这项研究中，研究了河流收敛弯道中墩周围冲刷孔的最大深度和最大容积。具有170°会聚弯曲的实验模型的中心曲率半径为170 cm。准备了具有不同尺寸的圆柱和立方体形状的墩，并将其安装在90°会聚弯头的不同位置，以研究在清水模式下三个流量排放下的冲刷条件。另一方面，均匀粒度为d _50的天然砂 ＝ 1mm用作床材料。结果表明，墩周围冲刷孔的深度和体积随角度的增加而增加，因此冲刷孔的最大深度和体积在75°角处发生。此外，在所有情况下，圆柱墩周围的冲刷孔的深度和体积均低于立方墩。而且，冲刷孔的形状相对于通道的中心轴是不对称的，并且主要是孔向内弯曲的延伸。