Tests for static and fatigue performances of carbon fiber reinforced plastics pre-tighten single tooth connector
-
摘要: 通过试验研究了预紧力、齿长和载荷水平对碳纤维增强树脂基复合材料(CFRP)预紧力单齿接头(PTSTC)静态和疲劳性能的影响。试验结果表明:CFRP PTSTC的疲劳极限承载力可以达到静态极限承载力的80%~85%,与螺栓等传统连接方式相比,其疲劳性能具有一定优势;预紧力可以显著改善CFRP单齿接头的静态和疲劳性能;CFRP PTSTC的静态极限承载力随齿长增加而升高,但是在相同载荷水平下增加齿长不一定可以延长接头的疲劳寿命,尤其是在低载荷水平下齿长增加反而会缩短疲劳寿命;在加载初期,PTSTC的疲劳裂纹快速萌生,之后扩展缓慢,在接近破坏前的几次循环中又骤然增大,预紧力可以减缓疲劳损伤的累积速率;疲劳过程中PTSTC的刚度衰退不明显,在前95%疲劳寿命阶段仅下降1%~4%,预紧力也可以减缓刚度的衰退速率。所得研究成果可为复合材料接头抗疲劳设计提供参考依据。
-
关键词:
- 碳纤维增强树脂基复合材料 /
- 预紧力单齿接头 /
- 疲劳 /
- 滞回环 /
- 损伤累积
Abstract: The effects of pre-tighten force, tooth length and stress level on static and fatigue performances of carbon fiber reinforced plastics (CFRP) pre-tighten single tooth connector (PTSTC) were investigated by tests. The test results show that the fatigue ultimate load-capacity of CFRP PTSTC reaches to 80%-85% of the static ultimate load-capacity, and comparing with traditional connection methods such as bolt connection etc., the fatigue performance of it has advantages at some degree. The pre-tighten load can improve the static and fatigue performances of CFRP single tooth connector significantly. The static ultimate load-capacity of CFRP PTSTC increases with the tooth-length increasing, but increasing the tooth-length would not necessarily improves the fatigue life of the connector under the same load level, especially, the fatigue life reduces with the tooth-length increases under lower load level. The fatigue crack of PTSTC initiates rapidly during the early loading period, then grows slowly, and propagates sharply again in the last few cycles before fracture. The pre-tighten load can slow down the fatigue damage accumulation rate. The stiffness degeneration during fatigue process of PTSTC is not obviously, which is only 1%-4% in the former 95% of the fatigue life. The pre-tighten load can also slow down the stiffness degeneration rate. The investigation conclusions obtained can provide references for the anti-fatigue design of composite connector.
点击查看大图
计量
- 文章访问数: 868
- PDF下载量: 750
- 被引次数: 0