Abstract: Polycarboxylate superplasticizer was used to disperse multi-walled carbon nanotubes ( MWCNTs) and four electrode method was used to study the influence of MWCNTs on the electrical resistivity and stress-sensing properties of multi-walled carbon nanotube-based cement composites (MWNTs/CC).The effect of several variables on the stress-sensing function was studied, e.g. MWCNTs content , maximum stress applied and loading rate .The results show that with the increase of the dosage of MWCNTs , the electrical resistivity of composites decreases gradually , and the polarization time reduces gradually .When the dosage of MWCNTs between 0.06wt% to 0.3wt%, the MWNT/CC exhibit excellent stress-sensing property and the optimum dosage of MWCNTs is 0.1wt%.When the samples were progressively loaded until failure , the maximum fractional change of electrical resistance is up to 70%.With the increase of maximum loading stress and loading rate , the ratio of electrical resistivity change increases gradually .

Key words: multi-walled carbon nanotube;cement composite;electrical resistivity;stress-sensing