潮流条件下单桩冲刷形态的实验研究

An Experimental Study on the Scour around a Vertical Cylinder in Tidal Flow

采用激光地形测量系统对单桩模型进行定常来流和潮汐流下的局部冲刷试验,获得了典型来流条件下单桩周围局部冲刷的床面形态,探讨了潮流作用下单桩周围床面的冲刷特性以及与定常来流作用下床面冲刷关系。实验结果表明,与潮流最大流速相同的定常来流实验结果相比,潮流作用下冲刷坑平面形态与定常来流显著不同,但二者的最大冲刷深度和冲刷平衡时间则基本相同;最大流速是潮流冲刷坑形态变化的主要因素。

The Laser Topographic Measurement System is developed and applied to measure the local scour around a vertical cylinder in steady flow and tidal flow.The typical local patterns of scour around the cylinder in different flow fields were obtained,while the scouring characteristics and factors between steady flow and tidal flow were also discussed.It turns out that under the same max-velocity,the field patterns in tidal flow differ remarkably from the ones in steady flow,however,the equilibrium duration and the equilibrium scour depth are similar in both situations.The max-velocity is a key factor of the tidal flow for generating local scouring.