Velocity and turbulence in a scour hole at a vertical-wall abutment

An experiment was conducted in a laboratory flume to measure the three-dimensional turbulent flow field, using an acoustic Doppler velocimeter, in a scour hole at a vertical-wall abutment under a clear water scour condition. The distributions of time-averaged velocity components, turbulence intensity components and Reynolds stresses at different vertical sections are presented. In the upstream, a large primary vortex associated with the downflow exists inside the scour hole. On the other hand, in the downstream, the flow field is chaotic due to the vortex shedding. The data presented in this paper would be useful for the development and validation of a flow field model, which can be used for the estimation of scour depth at bridge abutments.