Abstract
•The self-sensing and micro-structural properties of the cement paste are investigated.•Considerable enhancements in compressive strength by about 27 and 38% were achieved.•rGO addition has modified the pore and micro-structure of cement paste.•rGO–cement composites can be efficiently used as smart sensors for SHM application.
Reduced graphene oxide sheets (rGO) have unparalleled physical characteristics that make them effective reinforcing materials. This article explore the effect of rGO on mechanical properties, pore size distribution, micro-structural characteristics and self-sensing properties of the hardened cement paste. The rGO were introduced to net cement paste at different percentages of 0, 0.01, 0.02, 0.03, 0.04 and 0.05 wt% of cement. Compressive strength was measured at 28 days of hydration. The rGO sheets were characterized by high-resolution transmission electron microscope (HRTEM) and Raman spectroscopy. The rGO/cement composites were characterized by Thermo-gravimetric analysis (TGA) pore size distribution and scanning electron microscopy (SEM). Finally; peizoresistive measurements have been performed to study the self-sensing properties of rGO/cement composites. The obtained results revealed that, considerable enhancements in compressive strength by about 27 and 38% were achieved by incorporating 0.04 rGO and 0.05% rGO, into cement matrix respectively. The integration of rGO into cement has significantly reduced the pore size of the rGO–cement composites and led to a considerable improvement in the microstructure. Based on the obtained results, the rGO-cement composites can be efficiently used as piezoresistive sensors.