The influence of AC and DC electrical resistance and piezoresistivity measurements of CNTs/Cement composites

In this paper data on electrical resistance on unloaded condition and pressure-sensitive behavior under different levels of compressive stress of cement paste specimens containing different percentages (0.1%, 0.25%, 0.50% and 1.0% vs. cement mass) of multi-walled carbon nanotubes are presented. AC and DC measurements of electrical characteristics of multi-walled carbon nanotube/cement composites unloaded or subjected to compressive stress were carried out by using two-probe configuration. Experimental results of DC test were affected by the electrode polarization. Therefore, DC method requires a pre-power time to let electrical resistance reach a stable value. On the contrary, the AC measurement can eliminate the effect of capacitor charging and discharging on the pressure-sensitive responses of MWNT/cement composites.