Performance of Silt Protector in Three Dimensional Flow

摘要

Performance of silt-curtain in three dimensional sea is investigated through a series of experiments. It is found that there are three mechanisms to reduce concentration and flux of turbidity generated by the construction work from flowing out of the construction site enclosed with silt curtains. The first is the temporal storage of turbidity and retardation of the flow of turbidity around the curtain. The second is the acceleration of dispassion of turbidity caused by the turbulence generated around the curtain that decreases the peak value of concentration of turbidity. The last one is the reduction of flow velocity in the enclosed area. As a result, the diffusion time increases and the amount of turbidity settled down in the enclosed region increases. Taking these mechanisms into account a simple procedure to predict reduction of flow velocity and the flux of turbidity is proposed. The applicability of the proposed procedure is examined using experimental results. KEYWORD: silt curtain; turbidity; concentration; flux; advection and diffusion; settling