波流作用下大直径圆柱体基底周围最大冲刷深度预测

Forecast of the maximum scour depth around vertical cylinders of large diameter combined wave and current action

通过物理模型试验,对设置在沙质海床上大直径圆柱体建筑物在波浪与海流共同作用下,就圆柱体基底海床的冲淤形态及最大冲刷深度预测方法进行了研究;并根据试验结果,对影响圆柱体周围海床冲刷的各种因素进行了分析与探讨.试验结果分析表明:对浅海(0.07<h/L<0.28)相对较细颗粒的海床,当圆柱体相对直径D/L=0.3～0.7,影响圆柱体基底周围海床冲刷的主要因素是圆柱体直径D、波高H、波长L、水流速度vc及与海床土质有关的一些参数.着重对影响最大冲刷深度的主要参数进行分析,采用试验数据进行拟合,建立了预测波流共同作用下大直径圆柱体基底周围的最大冲刷深度的表达式.

The scour topograph and the forecast method of maximum scour depth of sand seabed around large diameter cylinder set up on sand seabed subjected to joint action of wave and current are studied by physical model test. Based on the data of model test, effects of serial factors on scour depth are analyzed and discussed. The experimental results show that for a shallow water (0.07<h/L<0.28), relative fine sand and in the range of relative cylinder diameter D/L=0.3~0.7, the important parameters affecting the scour around the cylinder are cylinder diameter D, wave height H, wave length L, current speed vc and sand seabed properties. The effects of important parameters on maximum scour depth are analyzed. By test data imitation method, an equation is given to forecast maximum scour depth around large diameter cylinders caused by joint action of wave and current.