An experimental study has been carried out to investigate effects of four flow-altering scour countermeasures placed around a foundation pile under currents only as well as under coexisting waves and currents. The cou...An experimental study has been carried out to investigate effects of four flow-altering scour countermeasures placed around a foundation pile under currents only as well as under coexisting waves and currents. The countermeasures are sacrificial piles, downstream bed sill, sleeve and slot in the pile. Their arrangements follow the suggested optimal configurations, with some of them slightly modified. In terms of the evolution of scour depth and bed topography around the pile, the scour countermeasures are evaluated, subjected to steady currents with or without irregular waves. A comparison between maximum scour depth with the countermeasures and one without the countermeasures demonstrates the efficiency of countermeasures. All the tested scour measures reduce the scour depth by 17.6%–42.6% under the action of currents only and 5.8%–24.0% under the combined action of both currents and waves. The results also show that it takes a shorter time for the scour depth to reach its equilibrium with the measures under either coexisting currents and waves or currents only than ones without the measures.展开更多
基金supported by the R.J.Gust.Richert Research Foundation,Stockholm(Stiftelsen fr teknisk vetenskaplig forskning till minne av R.J.Gust.Richert)the National Natural Science Foundation of China(Grant Nos.51079072 and 51279088)the State Key Laboratory of Hydroscience and Engineering(Grant No.2013-KY-3)
文摘An experimental study has been carried out to investigate effects of four flow-altering scour countermeasures placed around a foundation pile under currents only as well as under coexisting waves and currents. The countermeasures are sacrificial piles, downstream bed sill, sleeve and slot in the pile. Their arrangements follow the suggested optimal configurations, with some of them slightly modified. In terms of the evolution of scour depth and bed topography around the pile, the scour countermeasures are evaluated, subjected to steady currents with or without irregular waves. A comparison between maximum scour depth with the countermeasures and one without the countermeasures demonstrates the efficiency of countermeasures. All the tested scour measures reduce the scour depth by 17.6%–42.6% under the action of currents only and 5.8%–24.0% under the combined action of both currents and waves. The results also show that it takes a shorter time for the scour depth to reach its equilibrium with the measures under either coexisting currents and waves or currents only than ones without the measures.
