单丝20 mm碳纤维含量对CFRC梁抗弯性能的影响试验  

Effect of 20 mm carbon fiber content on flexural properties of CFRC beams

作　　者：游俊 李峰 YOU Jun;LI Feng(Guangdong Hualu Transportation Technology Co.,Ltd.,Guangzhou 510420,China;School of Architecture,South China University of Technology,Guangzhou 510655,China)

机构地区：[1]广东华路交通科技有限公司,广东广州510420 [2]华南理工大学建筑学院,广东广州510655

出　　处：《混凝土》2023年第5期124-127,133,共5页Concrete

基　　金：国家自然科学基金(51775157)。

摘　　要：为了提高碳纤维增强混凝土(Carbon Fiber-Reinforced Concrete,CFRC)的动态抗弯性能,研究了低速落锤冲击作用下,单丝20 mm碳纤维的CFRC抗弯性能。试验工况设置为6种碳纤维体积分数(0、0.20%、0.25%、0.30%、0.35%、0.40%)。主要结论如下:提出了结合化学分散剂的多级物理分散法,实现了长度为20 mm碳纤维在混凝土中以单丝态均匀分布,改善了20 mm碳纤维在混凝土中难分散的现状。当冲击速度为3 m/s时,随着碳纤维体积分数由0提高至0.40%,碳纤维体积分数为0.35%的CFRC梁断裂吸收能量最多,约为相同工况下素混凝土梁的2.3倍。长度为20 mm的碳纤维实现在混凝土的水泥相中呈单丝态均匀分散。基于本试验,相较于其他工况,碳纤维体积分数为0.35%的CFRC梁断裂耗能最多。该研究对提高CFRC梁的综合性能具有很好的实际应用价值,易于推广使用。In order to improve the dynamic flexural performance of carbon fiber reinforced concrete(CFRC),the flexural performance of 20 mm single-filament carbon fiber under low speed drop hammer impact was studied.The experimental conditions were set as volume fractions of six kinds of carbon fibers(0,0.20%,0.25%,0.30%,0.35%and 0.40%).The main conclusions are as follows a multi-stage physical dispersion method combined with chemical dispersant is proposed to realize the uniform distribution of 20 mm length carbon fiber in concrete as monofilament,and improve the current situation that 20 mm length carbon fiber is difficult to disperse in concrete.When the impact velocity is 3 m/s,with the increase of carbon fiber volume fraction from 0 to 0.40%,the energy absorbed by CFRC beam with carbon fiber volume fraction of 0.35%is the most,which is about 2.3 times that of the raw concrete beam under the same working condition.Carbon fibers with a length of 20 mm were uniformly dispersed in the cement phase of concrete in a monofilament state.Based on this test,compared with other conditions,the CFRC beam with carbon fiber volume fraction of 0.35%consumes the most energy when breaking.This study has a good practical value for improving the comprehensive performance of CFRC beam and is easy to be popularized and used.

关 键 词：碳纤维增强混凝土 抗弯性能 碳纤维 试验 均匀分布 断裂 

分 类 号：TU528.041[建筑科学—建筑技术科学]