Piezoresistive properties of strain-hardening cement composite with liquid-type multi-walled carbon nanotubes dispersed by ultrasonicator

Abstract

Abstract Multi-walled carbon nanotubes (MWCNTs) are a new type of nanomaterial with superior performance. They are frequently used in cement matrices to increase electrical conductivity and as a sensor for monitoring the health of building structures. However, MWCNTs agglomerate easily and are difficult to disperse, which makes their homogeneous dispersion in the matrix material the focus of exploration. In this study, the dispersion method of MWCNTs in strain-hardening cement composites (SHCCs) with corresponding piezoresistance is investigated along with the effects of dispersed and nondispersed MWCNTs on the resistive sensitivity of the composites under monotonic loading. The experimental results indicate that MWCNTs in cement matrix composites can be effectively dispersed by applying ultrasonic energy. In addition, they can significantly increase the piezoresistive sensitivity of the composite.