Concrete Hollow Block

Concrete Hollow Blocks have used in modern building industry, They are cost effective and better alternative to clay bricks by virtue of their good durability, fire resistance, partial resistance to sound, thermal insulation and high speed in construction.

Concrete hollow blocks are commonly used in residential, commercial mid-rise structures, and firewalls, Though there are lot of alternative products that already available in the market but still Concrete hollow block is still number one materials for wall and partition

Raw Materials

• Portland Cement
• Sand
• Water

The process involves in manufacturing Concrete Hollow Blocks:

• Proportioning
• Mixing
• Compacting
• Curing
• Drying 

Proportioning refers to the amount of cement, water and aggregates ratio needed to produce concrete desired quality products. the combined aggregate content in the concrete mix should not be more than 6  parts to 1 part by volume of Portland Cement. If the ratio in taken in terms of weight basis this may average approximately at 1:7 (cement: aggregate). The Water Cement ratio of .62 by weight basis can be used for concrete hollow blocks.

Mixing, the objective of thoroughly mixing of aggregates, cement and water is to ensure that the cement-water paste completely covers the surface of the aggregates

Compacting, the purpose of compacting is to fill all air pockets with concrete as a whole without movement of free water through the concrete. 

Curing, In general, care must be taken to properly cure concrete, to achieve best strength and hardness. This happens after the concrete has been placed. Cement requires a moist, controlled environment to gain strength and harden fully. The cement paste hardens over time, initially setting and becoming rigid though very weak and gaining in strength in the weeks following. In around 4 weeks, typically over 90% of the final strength is reached, though strengthening may continue for decades

Drying, Concrete shrinks slightly with loss of moisture. It is therefore essential that after  curing is over, the blocks should be allowed to dry out gradually in shade so that  the initial drying shrinkage of the blocks is completed before they are used in  the construction work. Hollow blocks are stacked with their cavities horizontal  to facilitate thorough passage of air.

Generally a period of 7 to 15 days of drying will bring the blocks to the desired  degree of dryness to complete their initial shrinkage. After this the blocks are  ready for use in construction work.