Experimental investigation of temporal evaluations of scouring downstream of culvert

The investigation of bed topography downstream of culverts is very important. Since bed topography goes through extreme changes through time, this study investigated the temporal evaluations of bed topography. Also, the bed level downstream of culverts, as one of effective parameters in topography in different time spans, was investigated. One of the most important findings of the study is that with increasing the experiment time and approaching the equilibrium moment, the change percentage of the maximum scour depth decreased. Also with changes to and decrease in the bed level downstream of the culvert, the change percentage of the depth scour decreased. Another salient finding of this study was that the maximum scour over the beginning durations of the tests in case of equal downstream level and culvert bed level was approximately equal to the maximum scour in cases where the downstream bed level differed from the culvert bed level by 0.067 and 0.13 times the culvert mouth width.