Abstract
Berms are used to control erosion and scouring by reducing the rate of surface runoff. In addition, the berms are expected to improve the stability of a slope. Regarding the standard for the gradient of excavation surfaces, which is covered by the Ordinance on Industrial Safety and Health, Japan (Articles 356 and 357), each excavation surface divided by said horizontal step, i.e., berm, can be regarded as an individual surface if the width of the step is 2m or more. This paper introduces regulations and design standards for the berm width and slope height for each institution. Then the analyses of the effect of berm width on the stability of slope and its failure mode are carried out using the Rigid-Plastic Finite Element Method.
