Is there any reaction of CaCO3 with the hydration compounds of the cement matrix (C2S, C3S, C3A), when mixed with water, in order to prepare laboratory mortar?
Nabil, I don't know if I understood your question correctly, carbonates tend to react with the aluminate fraction, leading to the formation of carboaluminates, which in turn shifts the equilibrium reducing the precipitation of monosulfate in favour of ettringite. There's quite a consolidated literature on the thermodynamics aspect of these reactions, see e.g. the work of Thomas Matschei.
Dear Nabil,
If your question relates to the hydroxylation reaction of cement (water + cement + CaCO3), my experience shows that CaCO3 behave as a inert filler. There is an important exception: if CaCO3 is much finer than the rest of the particles in the concrete, it behaves as a nucleation site for the cement hydrates precipitation. Due to this, the setting reaction and strength development usully become faster.
Dear Nabil,
calcium carbonate is inert during cement hydration process so it doesn’t react . If you spoke about calcium oxide , free, reactivity of course is stronger and it creates expansive minerals so you obtain CaCO3 or other calcium minerals like ettringite if you have enough sulphate source .
Minerals from your list are obtained depending on chemical and mineralogical nature of your cement. So to have C2S ,Belite, you need only enough clay content and temperature about 1150-1250°C , but if you need all minerals so even Celite and Alite you need more temperature at least 1450°C like ordinary Portland cement calcining.
Best regards
Alex Reggiani
Your question is too confusing Dear Nabil, i dont understand about your main point of view. Are you asking about the products of Calcium carbonate in cement after mixing of water OR you ask about the calcium carbonate reaction with water in cement?
In the manufacture of Portland limestone cement limestone is inter-ground with Portland cement clinker. The limestone in this case act as an aggregate filler material which considerably reduces the porosity of the concrete thereby improving its strength and durability. From Rafael Salomao's experience mentioned in his answer above the limestone acts as an inert material.
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