碳纤维混凝土动态力学特性试验研究  

Experimental study on dynamic mechanical properties of carbon fiber reinforced concrete

作　　者：吴伟[1,2] 冯虎 WU Wei;FENG Hu(Yellow River Water Conservancy Vocational and Technical College,Kaifeng 475004,China;Engineering Technology Research Center of Small Watershed Water Conservancy in Henan Province,Kaifeng 475004,China;Zhengzhou University,Zhengzhou 450001,China)

机构地区：[1]黄河水利职业技术学院,开封475004 [2]小流域水利河南省高校工程技术研究中心,开封475004 [3]郑州大学,郑州450001

出　　处：《复合材料科学与工程》2021年第10期13-18,共6页Composites Science and Engineering

基　　金：国家自然科学基金(51709125);西藏自治区科技厅重点研发计划(XZ201901-GB-15)。

摘　　要：为探究碳纤维混凝土在动载作用下的安全性,采用非金属超声波检测仪测量不同掺量下碳纤维混凝土试件纵波波速,采用扫描电镜试验观测碳纤维与混凝土间的黏结方式,并利用直径为74 mm的变截面分离式霍普金森压杆试验装置在不同应变率下对四种不同碳纤维掺量混凝土试件进行冲击压缩试验,分析其应力-应变曲线、峰值应力、极限应变和DIF(动态强度增强因子)变化规律。结果表明:随着碳纤维掺量的增加,试件纵波波速随之增大,碳纤维能够在混凝土试件内部形成空间网状结构,增强试件整体性;相同碳纤维掺量下,随着应变率的增大,试件峰值应力、极限应变和DIF都随之增大,试件存在明显的应变率效应;相同应变率作用下,随着碳纤维掺量的增加,试件峰值应力先增大后趋于定值,两者呈现出很好的二次函数关系,DIF随之增大,极限应变随之减小,两者呈现线性关系,碳纤维对混凝土试件的强度和整体性存在显著提高。In order to explore the safety of carbon fiber reinforced concrete under dynamic load,the longitudinal wave velocity of carbon fiber reinforced concrete specimens with different content was measured by non-metallic ultrasonic detector,and scanning electron microscopy was used to observe the bonding method between carbon fiber and concrete.The 74 mm diameter variable cross-section separated Hopkinson pressure bar test device was used to perform impact compression tests on four concrete specimens with different carbon fiber content at different strain rates,and analyze their stress-strain curves,peak stress,ultimate strain and DIF(dynamic intensity enhancement factor)change law.The results show that as the content of carbon fiber increases,the longitudinal wave speed of the specimen increases,and the carbon fiber can form a spatial network structure inside the concrete specimen to enhance the integrity of the specimen.With the same carbon fiber content,the peak stress,ultimate strain and DIF of the specimen increase with the increase of the strain rate,and the specimen has an obvious strain rate effect.Under the same strain rate,as the content of carbon fiber increases,the peak stress of the specimen first increases and then tends to a fixed value,and the two show a good quadratic function relationship.The DIF increases,the ultimate strain decreases,and the two show a linear relationship.The strength and integrity of the concrete specimens with carbon fiber are significantly improved.

关 键 词：碳纤维 SHPB 纵波波速 混凝土 动态力学特性 复合材料 

分 类 号：TB332[一般工业技术—材料科学与工程]