Influence of approach shape of debris flow on impact load subjected to open Sabo dam under an overturning experiment of open Sabo dam

Recently high intensity rainfall disaster induces some structural failure of steel pipe open Sabo dam. To prevent such failure of the dam, a new design concept is necessary at the severe load exceeding the present design load. However, influence of debris flow impact load on steel pipe open Sabo dam is not clear to make a design load. The study experimentally approaches a vertical load distribution shape and its time history based on comparison with a wedge approach shape or a front boulder concentrated shape. The load and moment action of a front boulder concentrated shape debris flow is greater than that of a wedge approach shape. Mechanism making the difference is made clear by observation of vertical detail measurement of impact load.