氯离子侵蚀下多壁碳纳米管掺量对混凝土耐久性能的影响

Effect of Multi-walled Carbon Nanotubes Content on Durability of Concrete under Chloride Ion Erosion

对掺多壁碳纳米管的混凝土进行氯盐溶液(3%的NaCl溶液)浸泡,通过试验检测混凝土的力学性能和抗氯离子渗透能力,探讨了不同碳纳米管掺量对混凝土抗氯盐侵蚀性能的影响规律。研究了氯盐侵蚀下,多壁碳纳米管混凝土质量变化、相对动弹性模量、抗压强度等性能指标的变化规律。结果表明,随氯离子侵蚀时间增加,多壁碳纳米管混凝土的力学性能呈现“先增大,后降低”的变化。当混凝土中多壁碳纳米管掺量(质量分数)为0.1%时,混凝土在氯盐浸泡中残余抗压强度提高最大,相比普通混凝土提高了35.67%。掺多壁碳纳米管的混凝土内部氯离子浓度始终低于未掺多壁碳纳米管的试样,并且,在碳纳米管掺量为0.1%时,混凝土抗氯离子渗透性能的增强效果最好。

The mechanical properties,chloride penetration resistance and retrograde resistance of multi-walled carbon nanotube concrete under the action of chloride solution(3%NaCl solution)are tested,and the effect of different content of carbon nanotube on the chloride resistance of concrete is discussed.The deterioration rules of compressive strength,mass change and relative dynamic elastic modulus of multi-walled carbon nanotube concrete under chloride erosion are also studied.The results show that adding 0.1wt%multi-walled carbon nanotubes into concrete can significantly alleviate the damage caused by chloride erosion to concrete.Compared with other contents,0.1wt%content has the greatest improvement on the residual compressive strength of concrete in chloride immersion,which is 35.67%higher than that of ordinary concrete.In different carbon nanotube content concrete,the chloride ion concentration in concrete mixed with multi-walled carbon nanotubes is always lower than that without multi-walled carbon nanotubes.Moreover,when the content of carbon nanotubes is 0.1wt%,the enhancement effect of chloride ion penetration resistance of concrete is the best.