To prepare the smart material, the group uses piezoresistive multi-walled carbon nanotubes (CNTs) as an admixture in cement concrete. The electrical resistance of the self-sensing CNT/cement composite is remarkably sensitive to compressive stress, and expresses a linear and reversible piezoresistive response. These findings indicate that this self-sensing nanocomposite cement has great potential for traffic-monitoring applications such as vehicle detection, weighing and speed measurement.

In addition, the team believes that self-sensing concrete could also be used to monitor the stress or deformation of bridges and other civil structures.

Next steps

There are still some issues that need to be examined before any real-world applications could occur. An important one is to find out the influence of environmental parameters such as temperature and moisture, on the composite's sensing functions.