基于圆形护圈调整桩基局部流场,护圈开孔进一步交换上下两侧水体,降低结构振动并减少桩基冲刷深度,从而维持风力机的正常运行。为验证开孔护圈的防护效果,开展不同开孔型式护圈防护下的单桩基础冲刷物理模型试验。通过设计9种不同型式的开孔护圈,探究护圈开孔形态、开孔数量和开孔位置对防护性能的影响。结果表明：护圈改变桩基边缘冲刷形态,护圈开孔可提高桩基前期冲刷速率;相比传统护圈,内侧开孔护圈和外侧开孔护圈防护效果较差,而中间开孔护圈可进一步减小单桩基础周围冲刷深度,并控制冲刷深度不均匀性,提升护圈防护效果。
Abstract
The local flow field around a pile foundation can be adjusted using a circular collar, which when perforated, facilitates the exchange of water between the upper and lower sides, thereby reducing structural vibrations and minimizing scour depth, ultimately maintaining the proper operation of wind turbines. To investigate the effectiveness of perforated collars as scour protection measures, physical model experiments were conducted on monopile foundation with various collar perforation patterns. Nine different collar perforation patterns were designed to explore the effects of perforation pattern, number, and location on the protection performance. The results indicate that the collar alters the scour pattern around the pile foundation, and collar perforation can increase the initial scour rate. Compared with traditional collars,collars perforated on the inner and outer sides exhibit lower protection effectiveness, while a perforated collar with perforations in the middle can further reduce the scour depth and control the unevenness of scour depth, thereby enhancing the protection performance.
关键词
海上风力机 /
桩基础 /
冲刷 /
水槽 /
开孔护圈
Key words
offshore wind turbines /
pile foundations /
scour /
flume /
perforated collar
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基金
国家自然科学基金面上项目（51479137）
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