碳纤维水泥基复合材料纤维分散性及导电性能试验研究

发布时间：2018-01-09 03:05

本文关键词：碳纤维水泥基复合材料纤维分散性及导电性能试验研究　出处：《郑州大学》2015年硕士论文　论文类型：学位论文

【摘要】：本课题属郑州市科技领军人才项目:碳纤维智能混凝土性能研究及在结构健康监测中的应用研究(131TLJRC674)。碳纤维水泥基复合材料(CFCC)是在普通水泥基材料中掺入一定量的短切碳纤维复合而成的具有机敏特性的智能材料。在CFCC的制备中,碳纤维能否均匀分散是决定CFCC导电性能及机敏特性能否稳定的关键因素之一。此外,碳纤维的掺入会影响水泥基材料的力学性能。因此,本文主要针对碳纤维在水泥基体中的分散性、CFCC的导电性能及相关力学性能进行深入的试验研究,以期得到分散性、导电性能及相关力学性能耦合良好的碳纤维水泥基复合材料。主要研究内容包括:(1)采用新拌料浆法和硬化试件电阻测试法研究了三种分散剂(MC、CMC、HEC)及其掺量对碳纤维在水泥基体中分散性的影响,试验结果表明HEC分散剂对碳纤维的分散效果最好,其最佳掺量为0.6%。(2)采用两种氧化溶剂(浓硝酸和次氯酸钠溶液)分别对碳纤维表面进行氧化处理,研究碳纤维表面氧化处理对碳纤维形貌、碳纤维分散性、碳纤维水泥砂浆(CFRM)内部界面结合特性和CFRM力学性能的影响。试验结果表明:经过两种溶液氧化处理后的碳纤维表面含氧官能团均有所增加,浸润性均得到提高;另外,由浓硝酸处理、次氯酸钠溶液处理、不处理三种状态下的碳纤维制得CFRM试件中,浓硝酸处理的CFRM抗折强度值最大,其次是次氯酸钠溶液。即纤维表面氧化处理一方面能提高纤维表面浸润性及碳纤维的分散性能,另一方面能提高CFRM的抗折强度。(3)在碳纤维分散性研究的基础上,研究了砂灰比、养护龄期、干湿环境等因素对CFRM导电性能的影响。最后研究了粗骨料最大粒径对碳纤维混凝土(CFRC)导电性能和抗压强度的影响,试验结果表明:粗骨料对导电性及抗压强度均存在最大粒径效应,即在粗骨料粒径为16mm时,CFRC导电率及抗压强度均达到最大。
[Abstract]:This project is a scientific and technological leader project in Zhengzhou City: research on the performance of carbon fiber smart concrete and its application in structural health monitoring. Carbon fiber cement matrix composites (. CFCC is a smart material with smart properties, which is composed of a certain amount of short cut carbon fiber in ordinary cement-based materials. The uniform dispersion of carbon fiber is one of the key factors to determine the stability of CFCC conductivity and cleverness. In addition, the addition of carbon fiber will affect the mechanical properties of cement-based materials. In this paper, the electrical conductivity and related mechanical properties of carbon fiber dispersion in cement matrix are studied in order to obtain the dispersion. Carbon fiber cement matrix composites with good coupling of electrical conductivity and related mechanical properties. The main research contents include: 1) three dispersants (MCs) were studied by using the new paste method and the resistance test method of hardened specimens. The effect of HEC and its content on the dispersion of carbon fiber in cement matrix was studied. The experimental results show that HEC dispersant is the best dispersant for carbon fiber. Two kinds of oxidation solvents (concentrated nitric acid and sodium hypochlorite solution) were used to oxidize the surface of carbon fiber, and the morphology of carbon fiber was studied. Carbon fiber dispersion. Effects of interfacial bonding characteristics and mechanical properties of CFRM on carbon fiber cement mortar. The experimental results show that the oxygen-containing functional groups on the surface of carbon fiber are increased after the oxidation of the two solutions. The invasiveness was improved. In addition, concentrated nitric acid treatment, sodium hypochlorite solution treatment, no treatment of three states of carbon fiber to prepare CFRM specimen, concentrated nitric acid treatment of CFRM flexural strength value is the largest. The second is sodium hypochlorite solution, that is, the oxidation treatment of fiber surface can improve the wettability of fiber surface and the dispersibility of carbon fiber on the one hand. On the other hand, it can improve the flexural strength of CFRM. The effect of dry and wet environment on the conductivity of CFRM was studied. Finally, the effect of maximum particle size of coarse aggregate on the conductivity and compressive strength of CFRC was studied. The results show that the maximum particle size effect exists on the electrical conductivity and compressive strength of coarse aggregate, that is, when the diameter of coarse aggregate is 16 mm, the conductivity and compressive strength of CFRC reach the maximum.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU528

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