What is white concrete made of?
The aggregates for white concrete are often completely white such as white marble, white quartz, calcined flint, synthetic white stone materials or natural pale lake or beach pebbles. Aggregates for white concrete must be frost-resistant and free of dust and sludge.
What type of cement is white cement?
White portland cement
White portland cement has essentially the same properties as gray cement, except for color. It is readily available throughout North America. The color of white cement is determined by its raw materials and the manufacturing process.
What is the composition of cement?
As described in it, cement is a powdery substance made with calcined lime and clay as major ingredients. Clay used provides silica, alumina, and iron oxide, while calcined lime basically provides calcium oxide….1. Introduction.
| Compound | Belite (dicalcium silicate) |
|---|---|
| Formula | Ca2SiO4 [2CaO·SiO2] |
| Notation | C2S |
| wt.% | 20 |
What is used in making white Portland cement?
This cement is made from raw materials containing very little Iron Oxide and Manganese Oxide. These oxides influence whiteness and undertone of white Portland cement. Generally in white cement China clay is used, together with chalk or limestone.
What are the raw materials for white cement?
This must be taken into account already in the selection of the raw materials proper. White cement is made from raw materials with a low content of colouring elements such as Fe, Mn, Cr and Ti. Use is made of high-grade limestone or chalk containing less than 0.15 wt.% Fe2O3
What are the problems with making white cement?
The problems involved in the manufacture of white cement The content of Fe2O3in white cement may vary over the range of 0.35 to 0.5 wt.%. If the limit is exceeded, the iron oxides are responsible for a greenish shade of the clinker which would be undesirable for example for architectural applications of white cement.
What should the temperature be for making white cement?
On the other hand, presence of these compounds allows the raw material to sinter at temperatures between 1350 and 1400 °C. The white cement clinker may thus be produced at temperatures lower by about 200 °C below the usual sintering temperature of traditional raw material mixes for white cement.
What is the silicate strength of white cement?
White cement is manufactured in strength classes of 325, 400 and 475. The typical silicate module of a white cement clinker is 4 to 6 (in contrast to 2.3 – 3 of grey Portland cement), and its aluminate module is 15-20 (that of grey Portland cement being 1.5 – 2.5). MS= SiO2/(Al2O3+ Fe2O3) MA= Al2O3/Fe2O3
