Thermal performance, freeze-and-thaw resistance, and bond strength of cement mortar using rice husk-derived graphene

We explored the thermal performance, bond strength, and freeze-and-thaw resistance of mortar composite incorporating rice husk-derived graphene-like material (GRH). These three features are key for road pavement application, especially against ice and snow on its surface. Groups of GRH mortar prisms (20 × 20 × 50 mm, 50 × 50 × 100 mm) were tested to examine heating and cooling performance, in comparison with other carbon-based materials: multi-walled CNT, graphene platelets, and carbon fibers. Additionally, thermal performance was assessed in terms of GRH wt% insertion. GRH cubes of 50 mm with different wt% were tested to capture freeze-and-thaw resistance for 300 cycles. XRD, Rietveld, and SEM-EDS analyses of calcium silicate hydrate (CSH) gels of undamaged/damaged cubes with/without GRH were compared at the age of 120 days after casting. A group of Φ 100 × 200 mm slanted concrete cylinders was tested with a 10-mm-thick overlay with different wt% GRH. The compressive failure load and fractured area were used to evaluate the bond strength of the GRH thin overlay.