Reactivity and performance of limestone calcined-clay cement (lc3) Cured at Low Temperature

Abstract

Limestone calcined-clay cements (LC3) take advantage of the synergetic effects of calcium carbonate reaction with the additional aluminium provided by the calcined clay. As temperature decreases, calcium carbonate solubility increase, therefore, the early-age hydration kinetics and the optimal proportioning of the ternary cement system are modified. This study explored the reactivity and mechanical performance of different LC3 systems cured at 10 and 20 ºC. Mixtures containing PC, PC-limestone and a LC3 blends with 50% clinker factors and 2:1 clay-to-limestone ratio were cast and compared. Hydration kinetics were assessed using isothermal calorimetry at each of the temperatures. The evolution of porosity was studied during hydration by MIP. Compressive strength was measured over time on cement paste cubes. Phase assemblage was monitored using XRD.