“Scour bed morphology caused by partially free and submerged flow at pipe culvert”

Abstract

ABSTRACT Scour is the most dangerous hazard that can affect waterways, since it is responsible for more than sixty percent of the failures that have been reported, including the scour that is caused by floods at water structures. The influence of partially free and submerged flow at a pipe culvert on scour bed morphology was experimentally studied. In addition, three different diameters of the pipe culverts that were used with four Froude numbers for seven different water depths upstream of the culverts were included. The results show that at low Froude number for different heights of water, upstream and downstream are slightly different regarding the height of the water. To illustrate, at high Froude numbers, the height of the water has a very slight difference upstream, whereas there is a large and noticeable decrease in water heights and an increase in velocity downstream. When the height of water increases, the scour depth increases upstream and downstream. The increase downstream is more noticeable. That is because the scour increases when the submergence ratio and water velocity increase, in addition to the water depths with high submergence ratios cause a larger scour hole.