Influence of approach shape of debris flow on impact load to open Sabo dam in experiment

Recently, the magnitude of landslide caused by torrential rain and typhoons is increasing in Japan. This high intensity rainfall disaster induces some structural failure of steel pipe open Sabo dams. Thus, current static design loads and impact loads are being considered. To prevent some structural failure of the dam, a new design concept is necessary at the severe load that is exceeding the present design load. However, the 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 a comparison with a wedge approach shape and 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.