Self-sensing Property of Cementitious Nanocomposites Hybrid with Nanophase Carbon Nanotube and Carbon Black

摘要

Cementitious composite filled with only 0.1 wt% multi-walled carbon nanotube (MWCNT) (MNTCC), or hybrid with 0.1 wt% MWCNT and 0.5 wt% nanophase carbon black (NCB) (NB/MNTCC), were prepared employing surfactant ultrasonic dispersion and subsequently high-speed mixing process. The electrical resistivities (ρ), compressive stresses (σ), and longitudinal strains (ε_l) of these cured nanocomposites under cyclic loading (10 times) were simultaneously collected, to investigate their piezoresistivty properties. Results revealed that, hybrid of NCB is very effective for enhancement on the stress/strain sensitivity of NB/MNTCC (the strain sensitivity up to 107, much higher than that of MNTCC 67), but there is almost no improvement on the self-sensing repeatability and variation stability of the corresponding nanocomposite.