玻璃纤维增强树脂基复合材料夹芯板-钢板连接接头的弯曲性能

摘要

以PVC泡沫或Balsa轻木为芯材的玻璃纤维增强树脂基复合材料(GRP)夹芯板目前广泛应用于船舶与海洋工程结构中.论文设计不同参数的 GRP夹芯板-钢板混合接头模型,进行四点弯曲加载下的静力及疲劳试验研究,同时运用 ABAQUS软件结合 MSC.fatigue软件对接头的静态及疲劳弯曲失效进行数值模拟,分析了接头的弯曲强度、刚度和失效模式,并研究了接头填充区材料及长度、钢板嵌入填充区长度等参数对接头弯曲性能的影响.结果表明:弯曲载荷作用下接头破坏发生在连接结合部,失效模式则因填充区的不同设计而不同;对提高接头的弯曲性能较为明显的设计参数包括将钢板延伸到接头填充区或者选择 Balsa 轻木替代 PVC 泡沫芯材;对于受到疲劳弯曲载荷的接头模型,在较大疲劳载荷水平下,所有试件在未达到 106次循环时均发生了疲劳破坏;而在相对较小的疲劳载荷水平下,经过 106次循环后所有试件全部完好,并且接头的剩余强度与疲劳试验前的静强度相近,表明小载荷水平下接头的疲劳次数对其承载能力无影响.%Glass fiber reinforced resin composite(GRP)sandwich panels with PVC foam or Balsa wood as core ma-terial are widely used in ship construction and ocean engineering.Flexural behaviors of hybrid joints of sandwich panel-steel plate which subj ected to static and fatigue loads respectively,were investigated with both numerical and experimental methods.Different parameter sets of hybrid joint specimens were designed and fabricated.Static and fatigue four-point bending experiments were implemented to study the bending strength,stiffness and failure modes of joints.ABAQUS and MSC.Fatigue softwares were also adopted to simulate their failure characteristics.The in-fluences of filler material,geometric length of filler and the inserted length of steel plate on the bending performance of the joint were respectively assessed.The results show that failure occurs near the filler area of joints under ben-ding load,and failure mode mainly depends on different filler parameters.Extending the steel end to filler area can obviously improve bending performance of joint,as well as adopting Balsa wood as filler material.All specimens are failed before 106cycles in the larger fatigue load case,while in the lower fatigue load case,all the specimens are nearly intact after 106cycles and their residual strengths are quite close to their static ultimate strength.It is indica-ted that fatigue cycles with smaller loading amplitudes have little influence on their loading capacities.