Abstract
Channels arranged with natural stones are constructed as irrigation and drainage channels with a concern for the environment. Studies on the hydraulic characteristics and the drag force on roughness elements with regular shapes, such as a cubic shape, have frequently been performed. But it is difficult for us to plan and design channels arranged with natural stones, because few studies of such channels have been conducted until now.
Among a series of studies on the hydraulic characteristics of channels arranged with natural stones, the drag force acting on a single roughness-element settled on a flume bed was measured, and factors influencing that force were analyzed. Important influencing factors were the forms of the stagnation area and the upstream side shapes of the roughness elements.
