Comparison of bond strength to aggregate between reactive magnesia cement (RMC) and portland cement (PC)

The aggregate-cement paste bond strength is one of crucial factors influencing the durability, overall mechanical performance and lifespan of concrete.This study for the first time compared the bond strength to aggregate between reactive magnesium cement (RMC) and traditional Portland cement (PC).The mechanical properties, including compression strength and bond strength, of RMC highly rely on the carbonation curing while carbonation curing slightly reduces the mechanical properties of PC.Even though under carbonation curing, the bond strength of RMC is still inferior to the PC, which is due to limited carbonation depth, as evidenced by XRD and TGA characterizations.The contribution of carbonation to the bond strength was calculated, showing that the RMC holds great potential to achieve greater bond strength compared with PC if the carbonation degree can be further increased.