Influence of infiltration on suspended sediment under waves

摘要

The effect of percolation through a permeable bed on sediment suspension under regular waves was examined in a laboratory wave tank(28 m×1 m×1 m), using acoustic backscatter sensors to make rapid(3 Hz)suspended sand profile measurements(0.005 m vertical resolution). Waves of 1.7 s period and heights ranging from 0.14 to 0.185 m were used over sand with a D_50 of 255μm. Infiltration velocities of 0-5.0×10~-4 m s~1 were used. With percolation through an initially flat bed, ripple development was suppressed, particularly at lower wave heights; ripples took longer to form and were more three- dimensional. Suspension was also suppressed.