Estimating the Maximum Outflow Discharge from Dam Breach using the Scaling Method

The aim of this paper is to investigate the scaling effect in modeling of the earthen dam breach process during the overtopping or piping. Small scale models are inexpensive but in most cases yield unreal results. In scaling the earthen dam breach phenomenon, the effect of grains detachment should be taken into account. In this article attempt is made to consider the effect of grains detachment in an appropriate way in the scaling method. For this purpose the results of real failed dams are utilized. A number of dams with a high height and a number of dams with low height were selected and it was assumed that the laboratory dams are replaced by the small dams. Then the ratio of their corresponding heights is taken as the scaling factor and the scale of grains detachment is calculated. Calculation of the maximum outflow discharge from dam based on this ratio yields an appropriate estimate of this parameter.