This paper studies the piezoresistive property of the CNT/cement composite to explore its feasibility as an embedded stress sensor for civil structures such as roadways, levees and bridges. The experimental results show that the electrical resistance of the CNT/cement composites changes proportionally to the compressive stress levels indicating the potential of using the CNT/cement composite as a stress sensor for civil structures. The piezoresistive responses of composite with different fabrication methods and CNT doping levels were also studied. It is found that the CNT dispersion-assistant surfactant could block the contacts among carbon nanotubes thus impair the piezoresistive response of the composite, while a higher CNT doping level could improve the sensitivity of the composite stress response. Currently, the piezoresistive property of the CNT/cement composite is being applied to develop an in-pavement traffic flow sensor.
Samenvatting