Model test investigation of offshore wind power monopile scour protection measures based on cemented riprap underwater
WANG Wei1, WANG Baizhi2,3, CHEN Songgui2, YAN Junyi4, JIN Feng5, JIANG Chaohua3
1. Institute of Science and Technology, China Three Gorges Corporation, Beijing 100038, China; 2. Tianjin Research Institute of Water Transport Engineering, Tianjin 300456, China; 3. College of Harbour, Coastal and Offshore Engineering, Hohai University, Nanjing 210098, China; 4. China Three Gorges Renewables (Group) Co., Ltd., Beijing 101100, China; 5. State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China
Abstract：Cemented riprap underwater technology uses good antidispersion performance and high-fluidity characteristics of underwater self-protecting concrete or mortar to fill the gaps between underwater blocks to form cement with a definite structural strength. This paper covers the first instance of cemented riprap underwater technology being applied to the field of scour protection for offshore wind power monopile foundations. Based on the cemented riprap underwater technology, this paper proposes anti-scouring measures for offshore wind power monopile rock-filled concrete, and uses a 1:13 large-scale wave current physical model test to study the anti-scouring performance of underwater structure around piles. Tests have shown that the plum-shaped pouring method can form a complete cemented riprap underwater protective structure. This protective structure can maintain good integrity and stability. Under extreme wave and current conditions with a return period of 50 and 100 years, the maximum scour depths of the sand around the monopile are 4.00 and 6.24 m, and the scour pit widths are 6.50 and 13.75 m, respectively. After the cemented riprap underwater protective structure, the maximum scour depths of the soil around the pile are 2.96 and 4.42 m, and the scour pit widths are 2.65 and 4.55 m, respectively. The above results provide new ideas for the protection measures and scour restoration of offshore wind power monopile foundations.
王卫, 王百智, 陈松贵, 闫俊义, 金峰, 江朝华. 海上风电单桩胶结抛石体防冲刷措施模型试验研究[J]. 清华大学学报（自然科学版）, 2022, 62(9): 1401-1407.
WANG Wei, WANG Baizhi, CHEN Songgui, YAN Junyi, JIN Feng, JIANG Chaohua. Model test investigation of offshore wind power monopile scour protection measures based on cemented riprap underwater. Journal of Tsinghua University(Science and Technology), 2022, 62(9): 1401-1407.
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2022, Vol. 62 
