细砾质斜坡海床上波浪的传播特性试验

Experimental study on wave propagation over fine gravel slope seabed

为了解波浪在渗透性良好的斜坡海床上的传播演变机制,在水槽中开展细砾质斜坡海床上波浪传播特性试验,研究海床土体孔隙水压力响应特征、波浪在斜坡海床上发生浅水变形区域内波浪近底水平流速特性以及波浪在可渗透斜坡海床上的传播演变特性。试验结果表明:海床中超静孔隙水压力随着波浪波高和周期的增大而增大;近底水平流速随着波浪浅水变形程度的增加而增加;波浪厄塞尔数越大,斜坡上波浪浅水变形越明显,各谐波之间的波波相互作用越剧烈;在浅水变形初段,海床渗透作用大于波浪浅水变形作用,在浅水变形剧烈区域,波浪浅水变形作用大于海床渗透作用。

In order to understand the wave propagation and evolution mechanism on the slope seabed of good permeability,the wave propagation characteristics on the fine gravel slope seabed were tested in the flume.The pore water pressure responsing characteristics of the seabed soil,the near-bottom horizontal velocity characteristics of wave in the shallow water deformation area of the slope seabed,and the wave propagation and evolution characteristics on the permeable slope seabed were studied.The experimental results show that the excess pore water pressure increases with the increase of wave height and wave period.It’s also found that the near-bottom horizontal velocity increases with the increase of wave shallowing degree.Meanwhile,with the increase of wave Ursell number,the deformation of wave shallowing on slope is more obvious,and the wave-wave interaction between harmonics is more intense.In addition,in the initial stage of wave shallowing,the seabed permeability is greater than the effect of wave shallowing,and in the area of severe wave shallowing,the effect of wave shallowing is greater than the seabed permeability.