INCEPTION OF SAND MOTION AROUND A LARGE OBSTACLE

[摘要] To select a material for the top layer of the scour protection in the vicinity of a large-scale offshore structure, it is required to know when the material starts to move as a result of waves and currents. But, inception of the motion of sand particles in a region, where diffraction wave superimposes on incident wave and the water particles depict a resulting orbit of ellipse, differs from that calculated by formulae established in the two dimensional wave field. This paper reveals the discrepancy in calculation when the conventional formulae were used and the data obtained by model experiment. It makes reference, also, to a possible method for a more accurate evaluation of the inception of motion.

[学科分类] 建筑学

[关键词] sand motion;motion inception;large obstacle