Raw material choose for concrete unburnt bricks

Raw material selection for concrete bricks

1. Clay: It must contain a certain amount of loose particles to facilitate mixing cement. Clay with less sand content can be mixed with sand. Clay with less sand content and harder must be ground before mixing with sand.

2. Cement: Adding 10% of 425# ordinary Portland cement can improve the strength and water resistance of the brick, and it will not crack after being soaked in water. Otherwise, general bricks will crack.

3. Admixture: Adding a small amount of admixture (reinforcement agent) can not only improve the hardening strength of the brick, but also reduce the amount of cement and reduce the cost of the product.

4. Water: The strength of the brick is high when the water content is appropriate. If the molding water content is low, the strength of the brick is poor, the material has great resistance in the mold, and the bottom of the brick is not dense when it is pressed on one side; if the molding water content is high, the bottom surface is wet and it is easy to be damaged when it is removed from the mold. When the water content of the sand is 3-5%, the water content during molding is preferably 10%. If there is too much fine sand in the raw material, it can be reduced to 8%.