短切碳纤维增强混凝土动态抗拉性能研究  

Study on dynamic tensile properties of short-cut carbon fiber reinforced concrete

作　　者：刘玉娟 王丽娟 LIU Yu-juan;WANG Li-juan(College of Construction Engineering,Zhengzhou Business University,Zhengzhou 451200,China)

机构地区：[1]郑州商学院建筑工程学院,郑州451200

出　　处：《复合材料科学与工程》2022年第9期97-101,132,共6页Composites Science and Engineering

摘　　要：由于混凝土抗拉、抗压强度的不均匀性,在混凝土中添加碳纤维可以改善混凝土的静态抗拉性能,提高拉压比。考虑到冲击和爆炸荷载对混凝土的破坏,本文研究了应力速率和碳纤维含量对混凝土动态抗拉性能的影响,并从细观层次上探讨其抗拉强度在动、静态性能上的差异。采用直径为74 mm的分离式霍普金森压杆(SHPB)装置,对含纤维体积分数分别为0‰、1‰、2‰和3‰的混凝土进行了动态劈裂试验。结果表明,随着纤维含量的增加,混凝土的静态抗拉强度明显增加,但增加的幅度有减小趋势。动态抗拉强度和动态强度增加因子(DIF)均随应力速率的增加而增加,表现出明显的率效应。碳纤维对混凝土动、静强度的影响存在显著差异。在设计混凝土配合比时,应适当选择碳纤维含量,以满足具体工况动、静态力学性能的要求。Due to the non-uniform tension and compression strength of concrete,carbon fiber can be added to concrete to improve its static tensile behavior and increase the tension-compression ratio.In view of the destructive consequences of impacts and explosions,the effects of the stress rates and carbon fiber contents on the dynamic tension behavior of concrete were investigated in this paper.And from the mesoscopic level,the difference between the dynamic and static properties of its tensile strength is discussed.The dynamic splitting tests of concrete with the fiber contents of 0‰,1‰,2‰,and 3‰were carried out by using a split Hopkinson pressure bar(SHPB)device with a diameter of 74 mm.We found that with the increase of fiber content,the static tensile strength of concrete increases obviously,but the increased amplitude tends to decrease.The dynamic tensile strength and dynamic increase factor(DIF)both increase with the increase of stress rate,but the growth rate slows down,showing an obvious rate effect.There are significant differences in the influence of carbon fiber on the dynamic and static strength of concrete.In the design of concrete mixing proportion,the content of carbon fiber should be appropriately selected to meet the requirements of dynamic and static mechanical properties.

关 键 词：碳纤维 SHPB 抗拉性能 DIF 细观 混凝土 

分 类 号：TB332[一般工业技术—材料科学与工程]