纳米碳纤维增强混凝土动态劈拉破坏的能耗规律 研究  

Energy consumption laws of carbon nanofiber reinforced concrete in dynamic splitting tensile failure

作　　者：王志航 白二雷[1] 潘璐 黄河[1] 聂良学 WANG Zhi-hang;BAI Er-lei;PAN Lu;HUANG He;NIE Liang-xue(School of Aviation Engineering,Air Force Engineering University,Xi’an 710038,China;93118 Troops of PLA,Beijing 100843,China;93125 Troops of PLA,Xuzhou 221005,Jiangsu,China)

机构地区：[1]空军工程大学航空工程学院,西安710038 [2]中国人民解放军93118部队,北京100843 [3]中国人民解放军93125部队,江苏徐州221005

出　　处：《工程爆破》2023年第4期10-17,共8页Engineering Blasting

基　　金：国家自然科学基金资助项目(51908548);国家人民防空办公室立项课题基金资助项目(RF20SC01J-S0);陕西省高校科协青年人才托举计划基金资助项目(20200415)

摘　　要：采用Φ100 mm SHPB试验装置对纳米碳纤维(CNFs)体积掺量为0、0.1%、0.2%、0.3%、0.5%的纳米碳纤维增强混凝土(CNFRC)进行了动态劈拉试验,分析了CNFRC动态劈拉破坏的能耗规律,并与碳纤维(CFs)体积掺量为0.3%的碳纤维增强混凝土(CFRC)进行了对比分析。结果表明:在动态劈拉破坏过程中,随着入射能平均变化率的增大,混凝土的应变率不断增大。采用二次多项式能较好地拟合应变率随入射能平均变化率的变化规律。CNFs可“加固”混凝土内部结构,从而使得CNFRC的应变率较普通混凝土小。CNFRC的吸收能具有明显的应变率效应和入射能平均变化率效应。在分析混凝土内部能量耗散时,建议采用入射能平均变化率作为自变量。CNFs可以提高混凝土的吸能特性和强度。入射能平均变化率相同时,随着CNFs掺量的增大,CNFRC的吸收能和动态劈拉强度均先增大后减小。CNFs掺量为0.3%时,CNFRC的吸收能和动态劈拉强度均最大。入射能平均变化率相同时,CNFs对混凝土强度的提高效果较CFs差,对混凝土吸能特性的提高效果接近CFs。Dynamic splitting tensile test was carried out on carbon nanofiber reinforced concrete(CNFRC)with carbon nanofiber(CNFs)volume content of 0,0.1%,0.2%,0.3% and 0.5% by using Φ100 mm SHPB test device.And energy consumption laws of CNFRC in dynamic splitting tensile failure were analyzed,which was compared with carbon fiber reinforced concrete(CFRC)with carbon fiber(CFs)volume content of 0.3%.The results show that the strain rate of concrete increases with the increase of the average change rate of incident energy in the dynamic splitting tensile failure process.Quadratic polynomial can be used to fit the variation of strain rate with the average rate of incident energy.CNFs"reinforce"the internal structure of concrete so that the strain rate of CNFRC is smaller than that of plain concrete.The absorbed energy of CNFRC has obvious effect of strain rate and average change rate of incident energy.It is suggested to adopt the average change rate of incident energy as independent variable when analyzing the energy consumption inside concrete.CNFs can improve the energy absorption property and strength of concrete.At the same average change rate of incident energy,the absorbed energy and dynamic splitting tensile strength of CNFRC increase first and then decrease with the increase of CNFs content.When CNFs content is 0.3%,CNFRC has the maximum absorbed energy and dynamic splitting strength.When the average change rate of incident energy is the same,the improvement effect of CNFs on concrete strength is worse than that of CFs,and the improvement effect on concrete energy absorption property is close to that of CFs.

关 键 词：混凝土 纳米碳纤维 碳纤维 动态劈拉 入射能 吸收能 

分 类 号：TU528[建筑科学—建筑技术科学] TD235[矿业工程—矿井建设]