多壁碳纳米管对粉煤灰混凝土的力学和耐久性能的影响  

Effect of multi-walled carbon nanotubes on mechanical anddurability of fly ash concrete

作　　者：吴亚敏 段君峰 张莉 侯风 WU Yamin;DUAN Junfeng;ZHANG Li;HOU Feng(School of Architectural Engineering,Zhengzhou University of Industrial Technology,Zhengzhou 451100,China;School of Civil and Ocean Engineering,Jiangsu Ocean University,Lianyungang 222005,China)

机构地区：[1]郑州工业应用技术学院建筑工程学院,郑州451100 [2]江苏海洋大学土木与港海工程学院,江苏连云港222005

出　　处：《功能材料》2024年第9期9229-9236,共8页Journal of Functional Materials

基　　金：国家自然科学基金项目(81350254);2023年度河南省重点研发与推广专项(科技攻关)(232102230030);2022年度河南省重点研发与推广专项(科技攻关)(222102320201)。

摘　　要：以聚乙烯吡咯烷酮(PVP)作为分散剂,结合超声工艺对多壁碳纳米管(MWCNTs)进行分散处理,配置出MWCNTs水性分散液,并将其作为掺杂相制备了粉煤灰混凝土,通过TEM、XRD、SEM、FT-IR、力学性能测试和快速冻融实验等方式研究了多壁碳纳米管掺量对粉煤灰混凝土的力学和耐久性能的影响。结果表明,PVP结合超声工艺能够有效分散MWCNTs,粉煤灰混凝土中加入MWCNTs能够加速水泥水化反应的进行,提高C-S-H和Ca(OH)2等水化产物的生成量。适量的MWCNTs掺杂后能够细化水泥内部孔结构,减少裂纹和大尺寸孔洞的数量,使粉煤灰混凝土的破坏形式由脆性断裂转变为韧性断裂。MWCNTs-0.3%试样的载荷峰值和形变量达到最大值,分别为41.6 kN和2.92 mm;抗压强度和抗折强度达到最大值,分别为60.5和11.2 MPa。经过100次快速冻融循环后,MWCNTs-0.3%试样的质量损失率为最低值0.271%,相对动弹性模量最大为84.34%,抗冻性能提升显著。Polyvinylpyrrolidone(PVP)was used as a dispersant and combined with ultrasonic technology to disperse multi walled carbon nanotubes(MWCNTs).A water-based dispersion of MWCNTs was prepared,and it was used as a doping phase to prepare fly ash concrete.The influence of multi walled carbon nanotube content on the mechanical and durability properties of fly ash concrete was studied through TEM,XRD,SEM,FT-IR,mechanical performance testing and rapid freeze-thaw experiments.The results indicated that PVP combined with ultrasonic technology could effectively disperse MWCNTs,and the addition of MWCNTs to fly ash concrete could accelerate the cement hydration reaction and increase the generation of hydration products such as C-S-H and Ca(OH)2.Moderate doping of MWCNTs could refine the internal pore structure of cement,reduce the number of cracks and large-sized pores,and transform the failure mode of fly ash concrete from brittle fracture to ductile fracture.The peak load and deformation of the MWCNTs-0.3%specimen reached their maximum values,which were 41.6 kN and 2.92 mm,respectively.The compressive strength and flexural strength reached their maximum values,which were 60.5 and 11.2 MPa,respectively.After 100 rapid freeze-thaw cycles,the mass loss rate of the MWCNTs-0.3%sample was the lowest value of 0.271%,and the maximum relative dynamic elastic modulus was 84.34%,indicating a significant improvement in frost resistance.

关 键 词：多壁碳纳米管 粉煤灰混凝土 分散剂 力学性能 抗冻性能 

分 类 号：TU528.01[建筑科学—建筑技术科学]