非对称开孔沉箱式防护设施撞击损伤试验研究

Experimental study on the impact damage of unsymmetrically perforated caisson protection facilities

圆筒式沉箱设施作为水下生产系统的新型防护结构,其在落锚撞击作用下的损伤问题,是工程领域和学术领域长期关注的焦点与难点。通过模型试验方法,对特殊的非对称开孔沉箱式防护设施撞击损伤特性进行研究,选用渤海通航区某水下生产系统沉箱式防护设施和该设施所在海域落锚作为原型,通过量纲分析,以撞击速度为主要相似性参数,确定了1∶11的模型试验相似比,对沉箱式结构和落锚进行缩比尺模型试验。重点关注落锚速度、落锚质量和撞击位置对非对称开孔沉箱式防护结构的损伤影响规律。研究结果表明:开孔附近区域,撞击能量主要以挠曲变形形式耗散,也通过振动形式耗散,撞击产生的损伤以挠曲变形为主,损伤程度较为严重;距开孔区域较远位置,撞击能量主要以振动形式耗散,撞击产生损伤以凹陷变形为主,损伤程度较小。

Caisson protection facilities are a new type of protective structure for underwater production systems.Its damage under the impact of anchor dropping is the center of attention in engineering and academic fields.The impact damage characteristics of the special unsymmetrical by perforated caisson type protection facilities were analysed through model tests.The test prototype was the caisson type protection facilities of an underwater production system in the navigation area of Bohai Sea and the anchor was dropped 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 was determined,and the caisson type structure and anchor dropping were simulated by scaled experiments.The structural damage characteristics of the caisson type protective structure with asymmetric openings were focused at different anchor dropping speed,with different anchor dropping mass and in different impact position.The results show that in the area near the opening hole,the impact energy is dissipated partially in the form of flexural deformation and partially in the form of vibration.The damage form caused by the impact is mainly flexural deformation,and the impact damage degree is rather large.In the area far away from the hole,the impact energy is mainly dissipated in the form of vibration.The damage form caused by impact is mainly concave deformation,and the impact damage degree is rather small.