Experiments were performed in a sand bed channel to investigate the effects of a mining pit on the hydrodynamics around circular bridge piers. Mean velocity profiles, Reynolds stresses, kinetic energy fluxes and scales of turbulence were analysed at critical locations along the channel bed as well as in the proximity of the pier. At the approach location where flow had passed over the pit and was approaching the pier, substantial increments in the near-bed velocities, bed shear stress and Reynolds stresses were observed. Dredging of the pit increased the strength of the horseshoe vortex in the scour hole region and also amplified the shedding frequency of trailing vortices at the rear of the pier. These effects may be instrumental in the alteration of local scour as well as erosion and deposition patterns around bridge piers.

中文翻译：

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采砂河道圆形桥墩绕流湍流研究

在沙床河道中进行了实验，以研究采矿坑对圆形桥墩周围水动力的影响。在沿通道床以及码头附近的关键位置分析了平均速度剖面，雷诺应力，动能通量和湍流尺度。在进水流经过井坑并接近墩台的进场位置，观察到近床层速度，床层切应力和雷诺应力有较大的增加。挖坑的工作增加了冲孔区域中的马蹄形涡流的强度，并且还扩大了码头后部尾随涡流的脱落频率。这些影响可能有助于改变局部冲刷以及桥墩周围的侵蚀和沉积方式。