2002 年 8 巻 p. 243-248
Bed protection works are designed in conditions that hydraulic jump occurred on that works。But recently riverbed height is apt to come down and hydraulic jump is occurred in that downstream. In this study, it is objected to make an appraisal method for degree of risk of old bed protection works and a method to insure safety in a modification of that works.
In this paper, it is described that movement of bed particle under bed protection works with hydraulic jump occurred in that downstream. And it is cleared that unsteady flow of hydraulic jump makes pressure reduction of separation flow and movement of bed particle under bed protection works.