Hollow Block:
Hollow blocks are being described as blocks with a core-zero area larger than 25% of a total surface area.
Its use of hallow blocks for masonry construction, often referred to by some as chb size or hallowblock, has indeed been quickly established which are higher than conventional construction materials such as bricks and stones.
Concrete blocks with a trading name such as siporex are available on the light-colored market. These hollow blocks enable the implementation of thinner walls, which eventually lead to increased floor space because the air space in the block is 25% of the total area of the block, saving the material.
Hollow Concrete Block Size:
- 0.40 m x 0.20 m x 0.30 m : normal hollow blocks size in construction, often referred to as the standard hollow block size.
- 0.40 m x 0.20 m x 0.20 m : hollow tiles.
- 0.40 m x 0.20 m x 0.10 m: the absorption of water in hollow solid blocks for partitioning will be less than 10%.
- In order to include blocks in the building, the total length and height of the wall must be set correctly such that a single block or a half-length block can be used.
- The blocks, sometimes known by the term chb dimension, are available with a regular face size of 440 x 215 mm, which is a common hollow block size in inches, and a width of 140 mm, and a standard size of 215 mm.
- Hollow blocks created, of cement small stones, stone dust but also sand are mostly not cheaper than bricks, but they also have other specialties. Such blocks, often referred to as cement block size or height of hollow blocks, have much more tensile strength, and the walls built from all these blocks, which some might call hollow blocks meaning, behave as thermal insulators due to various about there hollowness.
Advantages of Hollow Block:
- This will offer a new appearance and reduce the electricity bill and create an eco-sustainable construction environment.
- Strong hollow blocks require less upkeep and have sound, heat, and fireproof insulation.
- The joints in these blocks need less cement mortar, little to no plastering, thereby accelerating the building process.
- High dimensional precision and consistent finish make it the perfect construction material for constructing load-bearing structures and building partition walls.
- Such hollow concrete blocks have high-stress bearing potential and are also commonly used in building design activities.
- Concrete hollow blocks are lightweight and can also be used for constructing houses in earthquake-prone areas.
- This blocks are more cost-effective than most conventional wall or wall building systems.
- It is of high quality, high strength, uniform size, and shape.
- It therefore does not disturb the eco-system in such a manner that it is either environmentally sustainable or eco-friendly because the waste and local resources will be used for its manufacturing or production.
Disadvantages of Hollow Block:
- Hollow blocks have a poor bearing capacity as the average mass of wall decoration materials is decreased, and the load-bearing capacity is often reduced.
- It is really risky to hang large things on walls like this.
Application of Hollow Block:
Such blocks can be found in load-bearing towers, moderate apartment complexes, office buildings, farmhouses, rural housing shelters, tall buildings, institutional buildings, factories, etc.- It is found in facilities such as elevated apartment complexes, office houses, market premises, hospitals, and hotels, etc.
- It could be used as ground-level units including roadside walkways, garden walkways, interlocking pavement blocks for road-moving areas close to curbstones, exhibition grounds, petrol pumping stations, bus and train stations, and so forth.
- Often used in particular areas of use, including such tree guard frames for roadside as well as backyard plantations.
How to Make Hollow Block?
The manufacturing of concrete blocks consists of four simple processes:
- Mixing.
- Molding.
- Curing.
- Coating.
Some manufacturing plants manufacture only concrete blocks, while others can produce a wide range of prefabricated concrete items, including blocks, flat paving stones, and decorative landscaping, such as lawn edging.
1. Mixing for Hollow Block Manufacturers-
Sand as well as gravel are deposited outside during piles and transported to storage containers in the plant by means of a conveyor belt as required. Portland cement is processed in relatively large silos outdoors to shield it from moisture.
While the production process begins, the necessary quantities of sand, gravel as well as cement are shifted by gravity or through mechanical means to a weighted batcher that determines the proper quantities of each element.
Dry materials first flow into a static mixer in which they are mixed together for a few minutes. There seem to be different sorts of mixers that are widely used. One type, called a planetary or a pan blender, resembles a shallow pan with a lid.
The mixing blades are connected to the vertical rotary shaft inside the mixer. The other type is the horizontal drum mixer.
It looks like a coffee can be flipped on its side and has a mixing blade mounted to the horizontal spinning shaft inside the mixer.
Once the dried materials have been mixed, a minimum volume of water is applied to the mixer. If the site is built in an environment that is prone to extreme temperatures, the water also may flow across a heater or refrigerator to control its temperature.
At this time, combination chemicals as well as coloring pigments can also be added. The concrete then is blended in for 6 – 8 minutes.
2. Molding for Hollow Block Manufacturers-
When a load of concrete has been fully mixed, it is poured into an inclined bucket conveyor and delivered to an elevated hopper. The mixing loop starts again with the next load.
The concrete is moved from the hopper to another hopper on top of the block machine at a measured flow rate. The concrete is pressed down into molds in the block machine.
The molds consist of an exterior mold box holding a variety of mold liners. The liners specify the outside form of the block and the inside shape of the block cavities. At one time, as many as 15 blocks can be molded.
When the molds are full, the weight of the upper mold head on the mold cavities compacts the concrete. This compaction can be complemented by air or hydraulic pressure cylinders acting on the mold head.
Many of the block machines often use a brief burst of mechanical vibration to help assist compaction. The compacted blocks are forced down and out of the molds on a flat steel pallet.
The pallet and the blocks are moved out of the system and onto the conveyor line. In certain activities, the blocks travel under a spinning brush that eliminates loose material from the top of the blocks.
3. Curing for Hollow Block Manufacturers-
The pallets of the blocks are transferred to an automatic stacker or loader that positions them in a curing rack. Each rack carries a few hundred blocks.
When the rack is completed, it is rolled onto a set of rails and pushed into a curing furnace. The kiln is an enclosed space with the ability to accommodate many rack blocks at a time.
There are two basic types of curing furnaces. The most popular type is a low-pressure steam oven. In this form, the blocks are kept in the oven for one to three hours at room temperature to allow them to harden slightly.
Steam is then steadily added to increase the temperature at a regulated rate of not more than 60°F per hour (16°C per hour).
Standard weight sections are normally healed at such a level of 150F-165°F whereas lightweight sections are healed at a level of 170F-185°F.
Once the temperature is hit, the heat is turned off but the blocks are able to soak in warm, moist air for 12-18 hours. After drying, the blocks are drying by eliminating the wet air and increasing the temperature in the oven.
It requires approx 24 hours to complete the healing cycle. Some other form of furnace is a high-pressure steam furnace, also called an autoclave. In this form, the temperature is increased to 300-375°F, and the pressure is increased to 80-185 psi.
The blocks are permitted to soak for 5 to 10 hours. The pressure is then easily sold out, which allows the blocks to lose their stored moisture quickly. The autoclave method needs more electricity and a more costly furnace, but it can create blocks in less time.
4. Cubing For Hollow Block Manufacturers-
The rack of the cured blocks is rolled out of the furnace, and the pallets of the blocks are unpacked and put on the chain conveyor.
The blocks are pushed out of the steel pallets and the empty pallets are fed back into the block system to receive a new collection of molded blocks. If the blocks are to be turned into split-face blocks, they are first shaped together as two blocks.
When these double blocks have been healed, they pass through a splitter, which attacks them with a powerful blade in the segment between the two halves. This causes the double block to crack and to create a hard, stone-like texture on one side of each piece.
The blocks move it into a cube, which matches up each block and instead stacks it into a cube, three blocks along with six blocks deeper and three to four blocks wide. These cubes are taken out outside with a forklift and stored in storage.
FAQ: Hollow Block Construction
What are hollow blocks, and how are they different from traditional bricks or stones?
Hollow blocks are construction materials characterized by a core-zero area larger than 25% of the total surface area. Unlike traditional bricks or stones, they offer increased floor space due to their air space, leading to thinner walls and efficient material usage.
What are the standard sizes of hollow blocks used in construction?
Common hollow block sizes include 0.40 m x 0.20 m x 0.30 m for standard construction, 0.40 m x 0.20 m x 0.20 m for hollow tiles, and 0.40 m x 0.20 m x 0.10 m for partitioning with low water absorption.
What are the advantages of using hollow blocks in construction?
- Improved aesthetics, reduced electricity bills, and eco-sustainability.
- Enhanced insulation against sound, heat, and fire.
- Reduced need for cement mortar and plastering, expediting construction.
- High dimensional precision and consistent finish for load-bearing structures.
- Cost-effectiveness and environmental sustainability through local resource utilization.
What are the disadvantages of hollow blocks?
- Reduced bearing capacity compared to traditional materials.
- Risky for hanging heavy objects on walls.
Where are hollow blocks commonly used?
Hollow blocks find application in various structures such as towers, apartments, offices, farmhouses, institutional buildings, and more. They are also used in ground-level units like walkways and pavement blocks.
What is the manufacturing process of hollow blocks?
The manufacturing process involves four main steps: mixing, molding, curing, and cubing. It includes mixing sand, gravel, cement, and water, molding the mixture into blocks, curing them under controlled conditions, and finally packaging for distribution.
What curing methods are used for hollow blocks?
Curing methods include low-pressure steam ovens and high-pressure autoclaves. Low-pressure steam ovens maintain blocks at 150-185°F, while autoclaves subject them to higher temperatures and pressures for faster curing.
How long does the entire manufacturing process take?
The complete manufacturing cycle, from mixing to cubing, typically takes approximately 24 hours. However, variations in curing methods may affect the overall duration.
Are there specialized types of hollow blocks available?
Yes, specialized types include lightweight blocks, split-face blocks, and decorative landscaping blocks, offering versatility in construction and design.
Are hollow blocks suitable for earthquake-prone areas?
Yes, hollow blocks are lightweight and can be used in earthquake-prone areas, offering a balance between structural stability and construction efficiency.
