碰撞条件下碳纤维增强复合材料(CFRP)加固自升式平台桩腿的性能分析

Bearing capacity analysis for legs with carbon fiber reinforced Polymer(CFRP) strengthened of a jack-up offshore platform under collision

老龄化海洋平台在与船舶碰撞的碰撞事故作用下,会导致桩腿的变形,降低其承载性能。为了降低碰撞对桩腿受力性能的影响,提高桩腿的耐撞性能,提出了利用吸能能力较强的高强碳纤维增强复合材料(CFRP)加固平台桩腿局部损伤的方法。以某自升式海洋平台的桩腿为例,利用有限元法建立简化的碰撞模型,通过在局部损伤部位粘贴CFRP材料来提高桩腿的耐撞性能,验证CFRP加固方法提高其耐撞性能的有效性。研究表明,相同的碰撞条件下,在加固前碰撞力使桩腿产生了接近屈服强度的应力;在粘贴2层CFRP布后,桩腿吸收的能量下降56.8%,极值应力下降了8.66%。在粘贴CFRP板后,桩腿吸收的能量下降70.68%,桩腿的极值应力下降55.84%。随着CFRP厚度的增加其吸能的能力越强,桩腿的耐撞性能越好,提高了桩腿的受力性能。

An aging offshore platform was collided with ships, this led to deformation of its legs and its bearing capacity was reduced. In order to reduce collision force influence on performance of legs and improve anti-collision capacity of legs, a method of strengthening damaged legs using high strength carbon fiber reinforced polymer（CFRP） with good energy absorption ability was presented. The legs of a jack-up offshore platform were taken as an example to prove the validity of the method using FEM. The study showed that under the same collision condition, the stress of the legs unreinforced is close to the yield stress; when pasted with 2-layer CFRP cover, the energy absorbed by the legs drops by 70.68%, and the extreme stress drops by 8.66% ; when pasted with a CFRP plate, the energy absorbed by the legs drops by 56.8% , and the extreme stress drops by 55.84% ; with increase in thickness of CFRP, the energy absorption and anticollision capacities of the legs were better, the bearing capacity of the legs is improved obviously.