Overtopping Breaching of Noncohesive Homogeneous Embankments

Abstract

Homogeneous small-amplitude embankments were constructed in flumes from a range of uniform noncohesive materials and breached by overtopping flows under constant reservoir level conditions. Embankment erosion evolves from primarily vertical to predominantly lateral in nature. The breach channel initially erodes the downstream face of the embankment with an invert slope parallel to the face, the breach invert slope then progressively flattening to a terminal value by rotating about a fixed pivot point along the base of the embankment, the location of this pivot point being a function of the size of the embankment material. The breach channel is of a curved (hourglass) shape in plan. Below the water line, breach cross-section width