温度和湿度对P-CNT自感知混凝土压敏性的影响  

Effect of temperature and humidity on the pressure sensitivity of P-CNT self-sensing concrete

作　　者：孙敏[1] 朱浩然 庄伟 SUN Min;ZHU Haoran;ZHUANG Wei(College of Civil Engineering,Suzhou University of Science and Technology,Suzhou 215009,China;China Construction Fifth Engineering Bureau I,Changsha 410004,China)

机构地区：[1]苏州科技大学土木工程学院,江苏苏州215009 [2]中国建筑第五工程局一公司,湖南长沙410004

出　　处：《河海大学学报（自然科学版）》2024年第3期72-78,共7页Journal of Hohai University(Natural Sciences)

基　　金：江苏省研究生科研与实践创新计划项目(KYCX22_3291)。

摘　　要：为研究温度与湿度对自感知混凝土(SSC)感知性能的影响,通过低温等离子体改性处理技术对碳纳米管(CNT)进行官能团嫁接,使其在水性体系下获得较好的分散性,并将改性后的CNT(P-CNT)加入混凝土中制备P-CNT/SSC传感器,通过改变含水率与温度条件研究P-CNT/SSC传感器的极化效应与循环加载下的自感知性能。试验结果表明:过高或过低的含水率均不利于SSC的感知性能,其中变化最为明显的是饱水状态下的P-CNT/SSC传感器,其应力敏感系数下降89.8%,并且压敏曲线极不稳定;在变温试验中,P-CNT/SSC传感器的电阻率与温度之间呈现负相关性,高温和低温下的应力敏感系数相较于常温组试件,分别下降了约35.66%和44.53%,并且压敏曲线整体出现了上移或下滑的趋势;P-CNT/SSC传感器在工程应用中的最佳测试环境为常温、自然含水率。In order to explore the impact of temperature and humidity variations on self-sensing concrete(SSC)efficacy,the functional group of carbon nanotube(CNT)was performed by the low-temperature plasma modification to enhance the dispersion in aqueous systems.The resulting modified carbon nanotubes(P-CNT)were integrated into the concrete to form P-CNT/SSC sensors.Varying water content and temperature conditions were tested to assess the polarization effect of P-CNT/SSC sensor and SSC’s self-sensing capabilities under cyclic loading.Results show that too high or too low water content impaired SSC’s sensing abilities,with the most significant impact observed under full water conditions,leading to an 89.8% decrease in stress sensitivity coefficient and unstable pressure-sensitivity curves.Moreover,during temperature variation tests,P-CNT/SSC resistivity exhibited a negative correlation with temperature.Stress sensitivity coefficients decreased by approximately 35.66% and 44.53% at high and low temperatures,respectively,compared to room temperature specimens,and the pressure-sensitivity curves displayed upward shifts or downward slides.Thus,the study suggests that the optimal testing condition of P-CNT/SSC applications involves room temperature and natural moisture content.

关 键 词：自感知混凝土 碳纳米管 压敏性 低温等离子体改性 极化效应 循环加载 

分 类 号：TU528.41[建筑科学—建筑技术科学]