Self-sensing additives to scale up the PZR in different cement matrix composites

This paper presents the study of the self-sensing effect that the addition of a combination of carbon nanotubes (CNT) and carbon microfibers (CMF) has on different cementitious cement matrices for construction of energy infrastructure applications. The study considers: commercial high-performance mortar (HPM), lightweight concrete (LWC) and self-compacted concrete (SCC) as cementitious matrices in which different % of conductive admixtures were added. To define the most suitable % of admixture, matrixes percolation thresholds were characterized. Once the most conductive dosage was defined for each matrix, the piezoresistivity (PZR) effect of the hybrid composite was analysed by means of the four-pole method. It could be noticed that the addition of conductive particles, has a small influence on the mechanical properties of the matrices. PZR test carried out showed a variation of the electrical signal of the material when loading/unloading cycles were applied, meaning that they present a self-diagnosis property. • Test to measure the self-sensitive performance of the cement-based material (CBM). • Percolation threshold identification of carbon additions in different matrices. • L sensorcoef and GF as comparative sensitivity parameters of different cement matrices. • Evaluation of the self-sensing properties with fractional change resistivity under stress. • Modification of electrical and piezoresistivity properties of cement-based materials.