Abstract
Laboratory experiments were conducted on local scour and bed evolution around a cylindrical pier. Not only with a traditional non-submerged pier, but some cases with a submerged pier were explored. Experiments were carried out in both static and dynamic scouring conditions. Shape of a scouring hole around the pier, as well as backwater caused by the pier, is of particular interest.
The shape of the scouring hole in the submerged conditions is similar to that in the non-submerged condition, thus the maximum scour depth appears in vicinal front of the pier. The maximum scour depth reduces as the height of the pier decreases. A refined equation for estimating the maximum scour depth including the effect of variable pier height is proposed and shows good performance in the range tested here. Backwater in the upstream is not so noteworthy in the submerged cases.
