海上风电桩基“抛石+”复合防护方法试验研究  

Experimental Study on Methods for Composite Protection of ‘Riprap+'of Offshore Wind Power Pile Foundation

作　　者：卞旭旭 闫福根 于通顺[1] 李永成 童鑫 曾兴井 BIAN Xuxu;YAN Fugen;YU Tongshun;LI Yongcheng;TONG Xin;ZENG Xingjing(College of Engineering,Ocean University of China,Qingdao 266100,China;Changjiang Survey Planning Design and Research Co.,Ltd.,Wuhan 430014,China;Water Resources Bureau of Zizhong County,Sichuan Province,Neijiang 641200,China)

机构地区：[1]中国海洋大学工程学院,山东青岛266100 [2]长江勘测规划设计研究有限责任公司,湖北武汉430014 [3]四川省资中县水利局,四川内江641200

出　　处：《海岸工程》2024年第2期91-103,共13页Coastal Engineering

基　　金：国家自然科学基金项目(U2106224)。

摘　　要：针对现有海上风电基础冲刷防护措施的失效机理及薄弱之处,利用扰流环的驻涡原理降低了水流对抛石层的沉陷破坏、利用套筒固定抛石层从而减弱了抛石层的边缘破坏、利用仿生水草垫阻碍下潜水流及侧向来流的功能有效减弱了抛石层的剪切破坏,由此分别提出了“抛石+扰流环”“抛石+套筒”“抛石+仿生水草”三种新型复合防护方法,并按照3类复合防护措施的布置方式提出10种具体的复合防护设计。进一步开展物理模型试验,评估不同复合防护方法的防护效果。试验结果表明,海流作用下3类复合防护的防护效果均较好且明显优于抛石单独防护,防护效率均在66%以上。当抛石铺设范围为3倍单桩直径、抛石厚度为2倍的中值粒径,扰流环内部直径设置为2倍单桩直径、距离抛石层0.5倍桩径时,扰流环能够更好地发挥作用,使得到达抛石层以及周围泥沙的水流分散并且流速减缓,此种复合防护方法的防护效率为82.2%,能够达到理想的防护效果。For the failure mechanism and weakness of the existing scour protection measures for offshore wind power foundation,the standing vortex principle of disturbance flow ring is used to reduce the subsidence and destruction of the riprap layer by water flow,the riprap layer fixed with a sleeve is applied to weaken its edge destruction and a mat of biomimetic water grass,which has a function of hindering the diving flow and the lateral flow,is used to weaken the shear failure of the riprap layer.These three new types of riprap composite protection methods,i.e.'the riprap + disturbance flow ring','the riprap + sleeve' and 'the riprap + mat of biomimetic water grass',are proposed respectively,and based on the arrangement of the three new measures,10 specific composite protection designs are proposed.And then,physical model tests are carried out and the protection effects of different composite protection methods are assessed.The results show that under the action of ocean currents the protection effects of the three composite protection methods are all better than that of riprap protection alone,with a protection efficiency being above 66%.When the laying range of riprap is 3 times the single pile diameter,the thickness of riprap is 2 times the median particle diameter of riprap,the inner diameter of the disturbance flow ring is set up to 2 times the single pile diameter and the distance away from the riprap layer is 0.5times the pile diameter,the disturbance flow ring can play a better role,so that the water flow reaching the riprap layer and the surrounding sediments can be dispersed and the flow velocity can be slowed down.Such a composite protection method can be reached to 82.2% in protection efficiency and can achieve the ideal protection effect.

关 键 词：单桩基础 复合冲刷防护 物理模型试验 冲刷深度 冲刷防护效率 

分 类 号：TV92[水利工程—水利水电工程]