峡岛湍流海域水流力荷载计算方法探讨

Discussion on calculation method of turbulent flow force load in sea area of channel island

与常规明渠流断面流速对数分布形态不同,外海连岛间海域断面流速呈现出复杂的分布特征,其主要原因在于凹凸不平海床面对海域流场分布有很大的影响。通过室内模型试验发现,峡岛湍流海域垂线流速基本呈二次抛物线分布形态,随后通过分析计算提出了以等效坡度为主因子的湍流流速分布公式。该公式计算结果与现场实测结果比较吻合,同时还给出了以抛物线分布形态为基准的水流力荷载计算修正系数。研究成果可为峡岛海域的工程结构设计提供参考。

In contrast to the logarithmic distribution of the flow velocity in the open channel section,the cross-section velocity in sea area of channel island presents complex distribution characteristics because the uneven sea bed has a great influence on the distribution of the flow field in the sea area. Through the indoor model test,it was found that the vertical velocity in the turbulent sea area of the channel island was in the form of a quadratic parabola,and then through the analysis and calculation,the turbulence velocity distribution formula was put forward,which takes the equivalent slope as the main factor. The calculation results of the formula were in good agreement with the field measured results,and the correction coefficient of the flow load calculation based on the parabola distribution pattern was also given. The study can be used as a reference for the engineering structure design in the sea area of channel island.