Let us now go into details to learn what is raw materials for concrete blocks, choose your suitable ration of concrete blocks.

Introduction of Different Raw Materials

Concrete hollow block can be produced by concrete block making machine, the product is mainly used to fill the high-level framework of the building, because of its lightweight, sound insulation, good thermal insulation effect, the majority of users trust and favor. The raw materials are as bellows:

  • Cement. powdery hydraulic inorganic cementitious material.


After adding water and mixing, it can be solidified in air or hardened in water, and can firmly bond sand, stone and other materials together.

  • Sand. for concrete, it can be combined with cement molecules to increase the diffusion area of cement molecules and form cement slurry to enhance the hydration of cement.

Filling the voids between the stones and the stones together with the stones acts as a skeleton to improve the compactness and strength of the concrete.



It has a certain lubricating effect and improves the workability of the concrete mixture.

In the process of cement hydration, the heat of cement hydration is effectively reduced, and the cracks are generated when the volume of cement changes due to physical and chemical reactions.

It acts as an aggregate in various types of mortar and can effectively save cemented materials.

  • Gravel. The cement slurry shrinks fast, and the stone gravel acts to inhibit shrinkage and stabilize the volume.

Play the role of the skeleton. The sand fills the voids of the stones, and the cement fills the voids of the sand to form a dense pile.



The concrete mixture acts as a cohesive and water-retaining agent. Good sand and gravel grading to prevent segregation and severe bleeding. Reduce the cost of concrete.

  • Stone Powder. Stone will produce a certain amount of stone powder during the crushing and grinding process.

Stone powder can replace cement of equal quality, which can not only use resources reasonably to protect the environment, but also reduce the production cost of concrete bricks.

"Stone Powder"

It can promote the hydration of cement, reduce the heat of hydration, and improve the working performance of concrete. Stone powder can improve the water retention, slump and concrete strength of concrete.

  • Fly Ash. It’s with the lime in the effective calcium oxide in the water under the action of heat, generating more hydration products, to meet the required strength and other properties of the product.

It should be noted that the production of concrete hollow block, requiring a high strength of the same, it is also required to have low shrinkage values ​​of other properties and so on. Therefore, the fly ash which is more fineness will be better for the products.


"Fly Ash"

Fly ash can be used as a blend of cement, mortar and concrete, and become a component of cement and concrete.

Fly ash is used as raw material instead of clay to produce cement clinker raw materials, manufacturing burned clay brick, autoclaved aerated concrete blocks, foam concrete blocks, concrete hollow block.

  • Lime and limestone are used extensively as building materials and are important raw materials for many industries.

Limestone can be directly processed into stone and fired into quicklime. Lime has quicklime and slaked lime.


The main component of quicklime is CaO, which is generally in the form of a block, pure white, and pale gray or yellowish when it contains impurities.

Quicklime absorbs moisture or adds water to become hydrated lime. Its main component is Ca(OH)2.

  • Gypsum. Production of fly ash aerated concrete hollow block, all kinds of gypsum can be used.


It can inhibition of lime digestion, regulate lime digestion rate and reduce digestion temperature; increase body strength, so that body in handling, cutting, steam curing process can withstand all kinds of noise, reducing body injury.

Raw Material Ratio of Concrete Blocks

The raw materials are produced in a certain proportion to produce concrete bricks.

In order to reduce your cost, you can base the ratio table. Choose the right proportion of raw materials to produce concrete blocks.

If you want to produce burned free concrete hollow blocks, you can choose our automatic hollow block machine.

If you want to manufacture autoclaved fly ash bricks, you can choose to fly ash bricks machine.

If  you want to know the brick making machine price, contact us today, Lontto will give you the quotation ASAP.

In general, cement is more expensive, you can use more sand, or fly ash, stone powder. To reduce the amount of cement used. Can greatly reduce your costs.

The Formula of Non-Burning and Steam Curing-Free Concrete Blocks

The ratio of the following table is the formula of non-burning and steam-free concrete blocks.

Product Cement



Fly ash Medium sand Slag Gravel Stone powder Lime and admixture Water/ cement ratio




First level Third level
Hollow block 12 4 / 30 / 54 / / 0.3~


12 4 / / / / 84 /
8 / 50 7 / 35 / / MU5
8 / 50 / / / 42 /
Porous block 10 6 / 20 / 64 / / MU10
10 6 / / / / 84 /
12 / 47 5 / 31 / 5 MU5
12 / 47 / 36 / / 5
NOTE: 1) The size of the hollow block is 390*190*190mm;

The size of porous block is 240*115*90mm.

2) The above ratio is derived from the actual production data of some customers of LONTTO Group. However, due to the differences in materials in various countries, customers are requested to determine a reasonable mix ratio based on actual conditions.

The Formula of Autoclaved Fly Ash Brick

The following table is the formula of autoclaved fly ash brick. 

Use 2% Gypsum for Autoclave Steam Curing Fly Ash Bricks.

Ingredient/Materials Ratio
Fly Ash 70%
Quarry Dust or Sand 20%
Quicklime 8%
Gypsum 2% 

Uses 1% Gypsum and No Sand for Autoclave Steam Curing Fly Ash Bricks

Ingredient/Materials Ratio
Fly Ash 89%
Quicklime 10%
Gypsum 1%
chao zhang

Author: Chao Zhang

I am Chao Zhang, I have been working in the brick making industry for over 10 years. I have a deep understanding and research on various models of block making machines, especially automatic brick machines, concrete block machines, compressed earth block machines, clay brick machines, cement brick machines. I have a special understanding of this industry. I can help my clients choose the suitable brick machine and assist them in designing and building a brick production factory. If you want to know everything about brick making machines, please contact me. I am happy to help you.