上海交通大学学报

上海交通大学学报 >

2022 , Vol. 56 >Issue 5: 664 - 674

DOI: https://doi.org/10.16183/j.cnki.jsjtu.2020.346

船舶海洋与建筑工程

孔隙率对环形阵列圆柱结构局部冲刷的影响

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  • 1.大连理工大学 海岸和近海工程国家重点实验室, 辽宁 大连 116024
    2.浙江省深远海风电技术研究重点实验室, 杭州 311122
刘诗航(1995-),男,辽宁省沈阳市人,硕士生,从事水下结构物局部冲刷及防护研究.

收稿日期: 2020-10-22

  网络出版日期: 2021-09-22

基金资助

国家重点研发计划(2017YFC1404202);国家自然科学基金(51909028);国家自然科学基金(52071301);中央高校基本科研业务费专项项目(DUT19RC(3)015)

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Effect of Porosity on Local Scour Around Circular Array of Cylinders in Steady Currents

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  • 1. State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology,Dalian 116024, Liaoning, China
    2. Key Laboratory of Far-Shore Wind Power Technology of Zhejiang Province, Hangzhou 311122, China

Received date: 2020-10-22

  Online published: 2021-09-22

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摘要

通过物理实验研究了群桩结构在单向流作用下的局部冲刷问题,重点关注群桩结构孔隙率对局部冲刷的影响作用.物理实验设置中,在群桩模型外直径固定的条件下,通过改变单桩的数量改变群桩结构的孔隙率,主要研究群桩孔隙率对局部冲刷平衡深度、范围及时间尺度的影响作用.结果表明:模型的孔隙率对群桩周围的冲刷有着显著的影响作用.当孔隙率p>0.7时,冲刷主要由单元桩周围的冲刷决定;当p<0.5时,冲刷趋向于与群桩外直径相等的单桩冲刷的模式;当 0.5<p<0.7 时,冲刷结果呈现由局部到整体的过渡模式.此外,平衡冲刷深度为p0.67.

关键词： 局部冲刷; 单向流; 群桩; 孔隙率

本文引用格式

刘诗航, 娄晓帆, 唐国强, 王滨 . 孔隙率对环形阵列圆柱结构局部冲刷的影响[J]. 上海交通大学学报, 2022 , 56(5) : 664 -674 . DOI: 10.16183/j.cnki.jsjtu.2020.346

Abstract

The local scour around a circular array of cylindrical piles through physical model was studied under the live-bed condition, concerning the effect of porosity of the structure on the local scour development. The porosity of the model was achieved by varying the number of single piles, while the outer diameter of pile groups was kept as a constant. The effect of porosity on the equilibrium scour depth, the scour extent, and the time scale of scour was examined. It is found that the scour around the pile group is significantly affected by the porosity of the structure. As p>0.7, the resultant scour is mainly determined by the scour around each individual pile. As p<0.5, the scour is characterized by the pattern of one single pile with the same outer diameter as the pile group. As 0.5<p<0.7, the scour shows a pattern of transition from local scour to global scour. It is also found that the normalized equilibrium scour depth is a power function of p, with a power of approximately 0.67.

Key words： local scour; steady current; pile group; porosity

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