Abstract：Caisson protection facilities is a new type of protective structure for underwater production system. Its damage under the impact of anchor dropping is the center of attention in engineering and academic fields. This paper analyzed the impact damage characteristics of the special unsymmetrical perforated caisson type protection facilities through model tests. The test prototypes are the caisson type protection facilities of an underwater production system in the navigation area of Bohai Sea and the anchor drop in the sea area of the facilities. By dimensional analysis, taking the impact speed as the main similarity parameter, the model test similarity ratio of 1:11 is determined, and the caisson type structure and anchor drop are simulated by scaled experiments. This paper focuses on the structural damage characteristics of the caisson type protective structure with asymmetric openings under different anchor dropping speeds, different anchor dropping masses and different impact positions. The results show that in the area near the opening hole, the impact energy is partially dissipated in the form of flexural deformation and partially dissipated in the form of vibration. The damage caused by impact is mainly flexural deformation, and the impact damage is large; Far away from the hole area, the impact energy is mainly dissipated in the form of vibration. The damage caused by impact is mainly concave deformation, and the impact damage is small.
徐万海，李航，贺子琪. 非对称开孔沉箱式防护设施撞击损伤实验研究[J]. 振动与冲击, 2023, 42(22): 177-183.
XU Wanhai,LI Hang,HE Ziqi. Experimental study on the impact damage of unsymmetrically perforated caisson protection facilities. JOURNAL OF VIBRATION AND SHOCK, 2023, 42(22): 177-183.
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