夹芯复合材料T型接头弯曲疲劳损伤机制及剩余强度试验研究

发布时间：2018-04-19 19:56

本文选题：复合材料 + T型连接　；参考：《西安交通大学学报》2017年09期

【摘要】：为了解夹芯复合材料T型接头在弯曲疲劳载荷作用下的损伤特征模式及剩余强度特性,以疲劳加载试验机和万能材料试验机为测试平台,开展了该型接头的弯曲疲劳试验以及疲劳加载前后的静力弯曲破坏对比试验。通过接头疲劳加载前的静力弯曲破坏试验,获取了结构初始破坏载荷并观测了损伤特征模式。试验研究结果表明,在弯曲疲劳载荷作用下,接头结构刚度呈现渐进退化特征且随疲劳载荷峰值的上升呈加速趋势,接头的疲劳损伤模式主要为水平基座夹芯板两侧简支边界位置泡沫芯材的剪切损伤,泡沫芯材力学性能的退化导致结构刚度的渐进式下降。进一步的试验结果对比分析表明,该型接头的疲劳安全峰值载荷可取为结构初始损伤载荷的70%,在疲劳安全峰值载荷范围内并经历105次弯曲疲劳循环后,接头的初始刚度和极限承载弯矩与疲劳承载前基本相当。
[Abstract]:In order to understand the damage characteristics and residual strength characteristics of sandwich composite T-joints under bending fatigue loading, the fatigue loading test machine and universal material testing machine were used as test platforms. Bending fatigue tests and static bending failure tests before and after fatigue loading were carried out. The initial failure load of the structure was obtained by static bending failure test before fatigue loading and the damage characteristic mode was observed. The experimental results show that under the action of bending fatigue load, the stiffness of the joint structure presents a gradual degradation characteristic and accelerates with the increase of the fatigue load peak value. The fatigue damage mode of the joint is mainly the shear damage of the foam core at the simply supported boundary position on the two sides of the horizontal base sandwich panel, and the degradation of the mechanical properties of the foam core leads to the gradual decrease of the structural stiffness. Further comparative analysis of the test results shows that the fatigue safety peak load of the joint can be 70 times of the initial damage load of the structure, and the fatigue safety peak load is within the range of the fatigue safety peak load and has undergone 105 bending fatigue cycles. The initial stiffness and ultimate bearing moment of the joint are almost the same as those before fatigue loading.
【作者单位】：海军工程大学舰船工程系;
【基金】：国家自然科学基金资助项目(51479205)
【分类号】：TB33

【相似文献】