破碎波作用下单桩基础局部冲刷试验研究  

Experimental Study on Local Scour around Monopile Foundation in Breaking Waves

作　　者：陶钢 赵西增[1,3] 侯亚东 史子洁 胡志锋 Tao Gang;Zhao Xizeng;Hou Yadong;Shi Zijie;Hu Zhifeng(Ocean College,Zhejiang University,Zhoushan 316021,China;Key Laboratory of Estuarine and Coastal Engineering Ministry of Transport,Shanghai Estuarine and Coastal Science Research Center,Shanghai 201201,China;Ocean Research Center of Zhoushan,Zhejiang University,Zhoushan 316021,China;School of Marine Engineering Equipment,Zhejiang Ocean University,Zhoushan 316022,China)

机构地区：[1]浙江大学海洋学院,舟山316021 [2]上海河口海岸科学研究中心、河口海岸交通运输行业重点实验室,上海201201 [3]浙江大学舟山海洋研究中心,舟山316021 [4]浙江海洋大学海洋工程装备学院,舟山316022

出　　处：《水动力学研究与进展（A辑）》2024年第1期81-86,共6页Chinese Journal of Hydrodynamics

基　　金：国家自然科学基金项目(51979245);浙江省联合基金重点项目(LHZ22E090002);中央引导地方科技发展资金项目(2023ZY1021);河口海岸交通运输行业重点实验室开放课题项目(KLECE202303)。

摘　　要：破碎波在近岸地区会引起剧烈的泥沙运动,导致破碎带内单桩基础发生局部冲刷,严重威胁单桩基础结构稳定性。该文在波浪水槽中采用中值粒径0.32mm的原型沙铺设平床沙坑,开展破碎波单桩冲刷试验,规则波经过坡度1:20的斜坡后,浅化破碎在矩形沙坑区域,分析桩基和破碎点的间距与波长之比α对单桩基础最大局部冲刷深度Smax及冲刷形态的影响。研究结果表明:破碎波翻卷产生湍流以及流动的纵向发展是引起冲刷的重要因素,使得相对距离α与最大冲刷深度Smax密切相关;沙床在破碎波作用下形成沙坝和滩槽结构,持续影响单桩局部冲刷的演变过程,当相对距离α=0.35~0.55时,由桩基引起的净冲刷最为显著,同时在滩槽地形叠加下,桩周的最大局部冲刷深度可达0.5倍桩径。Breaking waves in nearshore areas can induce intense sediment movement,leading to local scour around monopile foundations within the surf zone,posing a serious threat to the stability of monopile structures.In this study,prototype sand with a median particle size of 0.32 mm is used to lay a flat sand bed in a wave flume for conducting experiments on the scouring of monopile by breaking waves.Regular waves passing over a slope with a gradient of 1:20 shoaled,broke in the rectangular sand bed area.In the research,the influence of the ratio(α)of the distance between the pile and the breaking point to the wavelength on the maximum local scour depth(S_(max))and scour morphology of monopile foundation is analyzed.The study results indicate that the turbulent flow generated by the overturning of breaking waves and its longitudinal development are crucial factors in causing scour,closely linking the relative distance(α)with the maximum local scour depth(S_(max)).Under the action of breaking waves,the sand bed forms sand bars and trough system,continuously affecting the evolution process of local scour around monopile.When the relative distance(α)is in the range of 0.35 to 0.55,the presence of the monopile causes the most significant scour,and the maximum local scour depth around the pile,superimposed with the bar and trough topography,can reach 0.5 times the pile diameter.

关 键 词：海上风电 破碎波 单桩基础 局部冲刷 

分 类 号：TV148[水利工程—水力学及河流动力学]