A.A.Voskoboinick, A.V.Voskoboinick, V.A.Voskoboinick, A.G.Marchenko, V.I.Nikishov Local bed scour with an arrangement of two bridges supports located in the wake one after another |
Applied hydromechanics, Vol. 8 (80) ¹ 3, (2006) |
| The results of the experimental investigations of local bed scour formation and development around bridge piers are reported. Influence of an arrangement of two bridges which are found in the wake one after another, on physics of the bed scour formation is shown. The scour before prismatic pier is caused by the bed interaction of the horseshoe vortical structures, the downflow along a frontal pier surface and lateral vortical systems which are arised at a separation of the incident flow with the forward edges of the prismatic pier. The bed scour before the multitubular pier in the form of grillage is connected by action of the horseshoe vortical system which is bending around grillage as a single whole, of the horseshoe eddies which are arised near each of the cylindrical pier of the grillage and jet-stream which is arised between forward piers of the grillage. The local bed scour before prismatic pier of the old bridge is increased at the supercritical flow velocities on the fine water and it's decreased at subcritical flow velocities on deep water at a positional relationship of two bridges locating in the wake one after another. |
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| TEXT LANGUAGE: Russian |