Experimental Investigation of Turbulent Flow Field at Downstream-Facing Round Nosed Pier

Bridge pier in a flow induce turbulence and vortices that increase the risk of sediment bed scouring. The turbulent flow field around downstream-facing round nosed pier in a scoured bed was examined experimentally. The opposite bridge pier was embedded in a non-uniform soil with d(50) = 1.45 mm and sigma(g) = 3.16. Experiments were carried out under live-bed condition. Flow velocities were measured with acoustic Doppler velocimeter. Measurement was conducted at the pier front. Result shows that the time-average velocity field, turbulent intensities and turbulent kinetic energy at different depths and distances from the original bed level differs. These results are benefiting for validation of three-dimensional flow model and turbulence close to the bridge pier.