纳米碳纤维增强混凝土耐久性试验  

Durability test of carbon nanofiber reinforced concrete

作　　者：王腾蛟 许金余[1,2] 彭光 孟博旭 WANG Tengjiao;XU Jinyu;PENG Guang;MENG Boxu(School of Aeronautical Engineering,Air Force Engineering University,Xi’an 710038,China;College of Mechanics and Civil Architecture,Northwest Polytechnic University,Xi’an 710072,China)

机构地区：[1]空军工程大学航空工程学院,西安710038 [2]西北工业大学力学与土木建筑学院,西安710072

出　　处：《功能材料》2019年第11期11114-11121,共8页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(51208507; 51378497);爆炸冲击防灾减灾国家重点实验室开放课题资助项目(DPMEIKF201406)

摘　　要：为研究纳米碳纤维对混凝土耐久性的改善效果,进行了不同体积掺量(0.1%,0.2%,0.3%,0.4%和0.5%)下纳米碳纤维增强混凝土的冻融循环实验、渗透实验以及碳化实验,另外通过SEM实验进一步探讨了纳米碳纤维对混凝土耐久性的微观改性机理。结果表明,纳米碳纤维能够通过纤维桥接、孔隙填充两种方式改善了混凝土的微观形貌,显著提高了混凝土的耐久性;掺量为0.3%时,纳米碳纤维增强混凝土的抗冻融性能、抗渗性能和抗碳化性能均达到最佳;冻融循环次数相同,随着纳米碳纤维掺量的增加,混凝土的质量损失率和抗压强度损失率均先减小后增大;混凝土的渗水高度和相对渗透系数均随纳米碳纤维掺量的增加呈现先减小后增大的趋势;相同碳化龄期下,随着纳米碳纤维掺量的增加,混凝土的碳化深度先减小后增大;但掺量为0.5%的纳米碳纤维增强混凝土的抗冻融性能、抗渗性能和抗碳化性能仍优于素混凝土。To study the effect of carbon nanofibers on the durability of concrete, the freeze-thaw cycle test, penetration test and carbonization test of carbon nanofiber reinforced concrete with carbon nanofibers with different volume(0.1%, 0.2%, 0.3%, 0.4%, 0.5%) were carried out. In addition, the microscopic modification mechanism of carbon nanofibers to concrete durability was further investigated by SEM test. The results show that the carbon nanofibers could improve the micro-morphology of concrete through fiber bridging and pore filling, significantly improving the durability of concrete. When the content of carbon nanofibers was 0.3%, the frost resistance, impermeability and anti-carbonization performance of carbon nanofiber reinforced concrete were the best. When the number of freeze-thaw cycles was the same, as the amount of carbon nanofibers increased, the mass loss rate and compressive strength loss rate of concrete decreased first and then increased. The seepage height and relative permeability coefficient of concrete decreased first and then increased with the increase content of carbon nanofibers. Under the same carbonization age, the carbonation depth of concrete decreased first and then increased with the increase content of carbon nanofiber. Frost resistance, impermeability and anti-carbonization performance of carbon nanofiber reinforced concrete with 0.5% of carbon nanofibers were still better than that of plain concrete.

关 键 词：纳米碳纤维增强混凝土 耐久性 抗冻融性能 抗渗性能 抗碳化性能 SEM实验 

分 类 号：TU528[建筑科学—建筑技术科学]