Chloride Penetration Resistance of Cement Paste Containing Different Contents of CNTs

Abstract

Abstract-This study explored the effect of adding different concentrations of carbon nanotubes (CNTs) on the resistance to chloride ions penetration of cement mortars through natural penetration of chloride ions and Mercury Intrusion Porosimetry. The experimental results of natural penetration of chloride ions showed that, the chloride ions penetration depth of the samples which added with CNTs were deeper than the control group which was without the addition of CNTs in the case of 35 days, 45 days, 55 days, 65 days of natural penetration of chloride ions, and the penetration depth increased with the content of CNTs. However, Mercury Intrusion Porosimetry (MIP) experimental results indicated that the porosity of cement mortar incorporated CNTs instead decreased, so the speculation that adding CNTs makes the porosity of the cement mortar specimens increase resulting in the increase of the penetration depth can be excluded. Another assumption was proposed that there may be a water film on the surface of the CNTs, and this water film can accelerate the penetrating speed of chloride ions as a convenient channel.