Archive for category: Industry information

The prefabricated house refers to the house prefabricated and assembled on site. It uses the latest cold-pressed light steel structure and various parts of the light-weight material to combine the various parts of the house, so that it has excellent heat preservation, sound insulation, fire prevention and insect protection, energy saving, earthquake resistance, Moisture-proof function. The common practice in domestic construction is on-site production. Although this method has certain advantages, it has disadvantages such as high energy consumption, heavy wet work, and inability to guarantee the quality of the building. Residential buildings abroad are mostly prefabricated and assembled on site. This is conducive to the realization of residential industrialization. Therefore, popularizing prefabricated houses is of great practical significance.

All countries began processing and construction of prefabricated houses as early as the 1970s, including block buildings, large slab buildings, box structures, and so on.

1. Block building

The prefabricated block material is used to build a prefabricated building with a wall. The block building has strong adaptability, simple production technology, simple construction, low cost, and can also use local materials and industrial waste. . Building blocks are divided into small, medium and large. Small blocks are suitable for manual handling and masonry, with a low degree of industrialization, flexibility and convenience, and wide use. Medium-sized blocks can be hoisted by small machinery, which can save masonry labor. Large blocks have now been replaced by prefabricated large panels.

2. Panel construction

Also known as large-slab building, it is assembled from prefabricated large-scale interior and exterior wall panels, floor panels and roof panels. It is the main type of fully fabricated building in the industrialized system. The equipment in the building often uses centralized indoor pipe fittings or box-type toilets to improve the degree of assembly. The main shortcomings of large-slab buildings are that they have greater restrictions on the shape and layout of buildings, and the internal partitions of large-slab buildings with small bays and lateral load-bearing lack flexibility, which have certain limitations in the use of residences.

3. Box building

A prefabricated building developed on the basis of sheet building. This kind of building has a high degree of factoryization and quick on-site installation. Generally, not only the structural part of the box is completed in the factory, but the interior decoration and equipment are also installed, and even furniture and carpets can be installed. The box is hoisted and can be used after the pipeline is connected.

A typical China structure is built with concrete hollow blocks, but right now there’s a better option available.
Autoclaved Aerated concrete or AAC blocks are made with inorganic material that make it stronger and more durable compared to what we commonly use right now.

Here are four reasons why you should consider using it instead of the old hollow blocks:
AAC Block Is a Lot Stronger Compared to Hollow Blocks
AAC blocks are able to support heavier loads without the need of steel reinforcement, unlike with concrete hollow blocks. They are also capable of withstanding strong seismic forces and impacts.
AAC Blocks Are Lighter
Despite its superior strength AAC blocks are so lightweight it can even float on water! AAC blocks reduce the dead load on foundations and is 70% percent lighter compared to traditional hollow blocks.

AAC Blocks Are Workable and Less Wasteful
There are times when a hollow block needs to be shaped in order to fit. To do this, you have to be extremely careful and use special tools or else the hollow block will break into pieces. But with AAC blocks, you can shape it according to your needs with ordinary woodworking tools without having to worry that you might break it.
Other Perks
Sound insulation – you do not need additional insulation materials because AAC blocks can significantly reduce noise pollution.
Great temperature insulation – AAC block walls give an estimated 30% of heating and cooling significance to the house or building. This means that you can conserve energy due to low thermal conductivity value.
Eco-friendly – as mentioned earlier, AAC blocks are made from inorganic materials including fly ash – an industrial waste that can be harmful to the environment if left neglected.

(1) Reduce wet work on the construction site, improve construction efficiency and shorten the construction period by about 1/2:

The use of blocks must increase the structural columns and anti-seismic waist beam, the single wall construction needs more than three days to complete. And the block wall needs to be plastered on both sides to meet the flatness requirements. The wall plastering is completed, and it needs more than 30 days to dry. Only after drying can the construction of the coating and painting process be carried out. Aerated concrete lightweight wallboard for field measurement, size processing and production, the construction of a single wall can be completed in one day at most, the wallboard for dry construction, there is no wet field operation. After the completion of the installation of the wall roughness error is not more than 3mm, the wall without plastering, the completion of the construction can enter the wall coating paint construction process.

(2) Save the project cost, the maximum savings of about $10 /㎡ :

① Compared with 200mm thick aerated concrete block wall, the lightweight wall plate eliminates the constructional column and waist beam in the block wall and reduces the consumption of steel and concrete; Metope need not hang net plastering, blow putty directly. Compared with the block partition wall, the project cost can be reduced by 15.00-25.00 yuan /㎡.

②Compared with the aerated concrete block wall, the slab does not need to set constructional column and concrete waist beam, and the vertical dry bulk density of light wall slab is no more than 650kg (conservative design value is 850 kg/m3); There are masonry mortar, concrete waist beam, constructional column and plastering mortar on both sides of the aerated concrete block wall (concrete bulk density is 2400 kg/m3, cement mortar bulk density is 2000 kg/m3). Under normal conditions, the comprehensive cubic bulk density is about 1300-1400kg. The lightweight wallboard is used to effectively reduce the bearing load of the structure; Design phase according to the plate bulk density calculation and structural load, can save the steel content of about 4-6kg/㎡;

(3) To meet the requirements of various technical indicators and increase the indoor area:

① 150mm thick aerated concrete lightweight wallboard meets the heat preservation, heat insulation and sound insulation indexes of 200mm thick aerated concrete block; Compared with the use of aerated concrete block wall, the thickness can be reduced by more than 50mm, reducing the space occupied by the wall and increasing the indoor usable area;

②The crack resistance performance of the wall board is more obvious than that of the block wall, because there are two layers of two-way steel mesh inside to strengthen and restrict its expansion and contraction, and the contact parts of the whole wall and beam column are filled with special binder, and few cracks appear; With the passage of time, the settlement of the wall will produce more cracks in the wall and wall side, and it is difficult to deal with the cracks once they occur.

③high seismic performance, after the relevant seismic load failure test, the plate in the engineering structure can resist 8.0 earthquake to the wall does not fall, even if the fracture, due to the connection of the steel mesh in the plate, but also to break and do not collapse;

④Compared with sandwich color steel composite plate, the fire performance advantage is more obvious in steel structure engineering. The plate is made of inorganic materials, which is non-combustible in case of fire. The fire resistance limit of 100mm thick can reach more than 3.5 hours.

Autoclaved aerated concrete, or AAC, is concrete that has been manufactured to contain lots of closed air pockets. Lightweight and fairly energy efficient, it is produced by adding a foaming agent to concrete in a mould, then wire-cutting blocks or panels from the resulting ‘cake’ and ‘cooking’ them with steam (autoclaving).

In Europe AAC has a long history of development, having been in use for more than 70 years. It has a moderate embodied energy content and performs well as thermal and sound insulation, due to the aerated structure of the material and its unique combination of thermal insulation and thermal mass. It is light, does not burn, is an excellent fire barrier, and is able to support quite large loads. It is relatively easy to work with and can be cut and shaped with hand tools including woodworking tools.

AAC relatively easy to work with, and can be cut and shaped with hand tools including woodworking tools.

Blocks are made to very exacting dimensions and are usually laid in thin-bed mortar that is applied with a toothed trowel, although more conventional thick-bed mortar can be used. Wall panels are storey height, reinforced and mechanically fixed. AAC can also be used in panel form for floor and roof construction. It has a long life and does not produce toxic gases after it has been put in place.

In building with AAC, most blocks are solid and uniform, but some are typically ordered with round cores approximately 3.5 inches in diameter. By aligning these cores at the corners of a building and at window and door openings, continuous vertical channels are created into which steel re-bar is placed and concrete grout is poured. At the top of a wall, specialized U-shaped blocks are used that create a continuous channel or trough into which re-bar is placed and concrete is poured—creating a structural bond beam.

Building with AAC blocks is quite different from building with standard hollow-core concrete blocks. Starting with a level footing, a thin-set mortar is laid down using a specialized toothed trowel that holds a scoop of mortar. The end of the adjoining block is also buttered with the mortar. The block is then set down and tapped into place with a rubber mallet.  It is so different from concrete block installation. It’s much easier to work with AAC 。In addition to standard-dimension blocks, AAC is available in a wide range of precast panels that are produced with steel reinforcement to meet specific needs.