Improving the cracking resistance of mortar by reduced graphene oxide

Abstract

The shrinkage cracking adversely impacts the long-life durability of cement composites. However, how to restrict the formation and evolution of cracking is still a challenge. Herein, we propose a new strategy to control the shrinkage strain and associated cracking of cement mortar by introducing reduced graphene oxide (rGO). The early-age shrinkage and cracking resistance experimentation of mortar are firstly investigated. Moreover, the shrinkage mechanism is carried out and the distribution of rGO in mortar matrix is analyzed by scanning electron microscopy and X-ray micro-computed tomography. The results show rGO aggravates the imbalance relationship of evaporation-bleeding water on the surface of mortar, which increases the plastic shrinkage value. The water retention effect of rGO contributes to the decrease of autogenous and drying shrinkage. The well-dispersed rGO reduces the number, total length and width of plastic shrinkage cracking. In conclusion, the incorporation of rGO enhances the cracking resistance of mortar and exhibits a promising potential for the long-term sustainable development of cement composites.