Foam concrete is a kind of concrete with lightweight and has ideal strength. Because of the hollow structure in foam concrete, it has the function of absorbing heat and isolating sound.
The density of foamed concrete is 300-1200 kg/m3, and the thermal conductivity is between 0.08-0.3W/ (m ·K).
Foam concrete is widely used in CLC blocks, lightweight partition panels, roof insulation, floor cushion construction, floor heating backfilling, and other occasions.
At the same time, foam concrete is also a good sound absorption material, which can be used in highway sound insulation boards, sound absorption boards, and other fields.
Generally speaking, foam concrete is a kind of building material with multi-function, environmental protection, and economy, which has a wide application prospect.
CLC Concrete Advantages
Foamed concrete has good physical properties, combining insulation and electrical resistance. It has many benefits that make it one of the best alternatives to building materials. For example:
Rapid assembly
Its low density and lightness allow for increased installation speed. It's also easy to work with because it's not a complex material to cut from.
Compressive strength
It varies with the density of the material. Obviously, the greater the density, the greater the resistance. You can even use it to build multi-level collective housing.
Resistance to water absorption
The concrete structure absorbs water much more slowly. It is a humidity regulator that absorbs any excess humidity or softens dry air. In this way, you can create a pleasant atmosphere in your home.
Thermal insulation
As we mentioned earlier, it maintains a comfortable and cool indoor environment in both winter and summer.
So, during the cold season, the interior will stay warm, and in the summer, we will be able to keep the interior cool. This will save a lot on air conditioning and heating costs.
Economical
Foamed concrete is 10 to 87 percent lighter than conventional concrete. This substantial reduction in weight represents significant savings when building foundations and structures.
Transport
As a light material, it weighs only half as much as similar materials. This makes shipping tasks, as well as working with it (cutting, hammering nails, sawing, etc.) much easier.
Durability
Porous concrete ages well over time. It's as durable as rock and doesn't break down.
Sound absorption
Only a small amount is absorbed by the concrete, and most of it bounces back into place. The noise that actually reaches the interior is minimal.
Versatility
It's a very versatile material when it comes to shape and form. It can be easily made into anything: arches, pyramids, angles, etc. Therefore, it adds to the aesthetic impact of the building.
Fire resistance
Due to its low thermal conductivity, foamed concrete has a very low heat flux. It is an ideal material for industrial, agricultural and administrative buildings.
Reduce waste
This is critical in areas of high seismic risk. If an earthquake occurs, the broken walls will collapse, but not as much as other traditional materials.
CLC Concrete Types
Pure CLC Concrete
Use portland cement, water, and prepared foams or gases. It has no solid aggregates. To make it, water is mixed with cement and then chemicals or foams are added, which must be mixed correctly to achieve cellular consistency.
Sanded CLC Concrete
It contains cement, water, selected foamed aggregate, and sand with a maximum diameter of 4mm.
Lightweight aggregate concrete
It is composed of pumice stone and tezontle instead of sand and stone. These aggregates must have strong compressive properties to increase compressive strength.
Foam concrete with expansive aggregate
The addition of these aggregates has been shown to help retain moisture when curing concrete in hot climates.
It is also a protective element for metal structure fire prevention.
Foam concrete containing dispersant additives
The dispersal effect of the additive helps hydrate the cement particles, improving compression resistance and increasing fluidity due to a reduced cement/water ratio.
Suppliers of Concrete Additives
TRUNNANO is a reliable foaming agents supplier with over 12-year experience in nano-building energy conservation and nanotechnology development.
If you are looking for high-quality CLC foaming agents, please feel free to contact us and send an inquiry. (sales@cabr-concrete.com)
We accept payment via Credit Card, T/T, West Union, and Paypal. TRUNNANO will ship the goods to customers overseas through FedEx, DHL, by air, or by sea.
The influence of cement foaming agent on the quality of foamed concrete is extremely critical. A good cement foaming agent can make high-quality foamed concrete. How the various performance indicators of cement foaming agent affect the quality of foamed concrete.
The more uniform the foam, the better, and the diameter of the foam should be one size
The ideal pore size distribution of the pores is as narrow as possible, that is, the pore sizes of the pores are required to be as consistent as possible, and the difference should not be too large. This corresponds to the requirement that the foam should be uniform and not different in size. The bubble diameters of the foam cannot be exactly the same, but should be basically similar, the bubble diameter range should be as small as possible, and the difference between the maximum bubble diameter and the minimum bubble diameter should not be too large. As mentioned earlier, the pores formed by the foam are required to be uniform, which can avoid the concentration of compressive stress at the large pores and reduce the compressive strength. If the size of the foam is not uniform, the stress is concentrated in the large foam, which is very easy to cause it to become a weak link and be the first to crack when under pressure.
The higher the foam stability, the better, and the longer the foam stabilization time, the better
The foam with good stability has tough liquid film and good mechanical strength, and is not easy to burst or deform excessively under the extrusion of the slurry. In addition, it has self-water retention, the water on the liquid film is not easy to be lost under the action of gravity and surface tension, and can maintain the thickness and integrity of the foam liquid film for a long time, so that the foam can be stored for a long time without bursting.
1. The stability of the foam has three effects on the pores: most of the foam will not disappear, and it will be fixed in the foam concrete after the initial setting of the slurry to form the pores. If the foam stability is not good, most or a small part of the foam will burst after pouring, and there will be few pores formed.
2. Foam with good stability, the slurry is not easy to deform too much under extrusion, and has a certain resistance to pressure to keep itself approximately spherical, which can eventually form spherical pores with good hole shape;
3. Foam with good stability, the liquid film is not easy to rupture in the slurry, and it is not easy to form the communication hole formed by the collusion of the gas after the rupture.
Therefore, what it ends up with is the ideal closed pore. The less stable the foam, the fewer closed cells and the more open cells. Therefore, the stability of the foam can not be based on just not collapsing after pouring, but should be based on three indicators that do not collapse after pouring, the final formed pores are approximately spherical, and are not connected to each other. Most people take non-collapse after pouring as the measurement standard of foam stability, which is actually a misunderstanding and the minimum standard of foam stability.
Foam stability can be measured by foam stabilization time when there is no standard testing instrument to measure its sinking distance. The foam stabilization time should meet the needs of the initial setting of the cementitious material used. Because after the initial solidification of the slurry, the foam can be fixed and the shape of the foam can be retained to make it into a pore.
Any cementitious material has an initial setting time, especially the most widely used ordinary Portland cement, the initial setting is mostly later than 45min. If the foam stability is poor, the cement and other cementitious materials have not yet set, and the foam has burst, then the foam cannot form pores in the concrete. In general, the minimum requirement for foam stability is to make the foam stabilization time longer than the initial setting time of the cementitious material by 10 to 20 minutes. Since the initial setting time of various cementitious materials is inconsistent, the requirements for foam stabilization time are also different. In general, the foam stabilization time for fast-gelling materials can be shorter, and the foam stabilization time for slow-gelling materials should be as long as possible. Even if the same cementitious material has different temperature, its initial setting time is different, and the change is quite large. For example, ordinary silicon cement may initially set in less than 40 minutes in summer, and will not initially set in 80 minutes in cold winter below 5 °C. Therefore, it is impossible to have a constant specific standard for the stabilization time of the foam, and it should be determined according to the situation. In order to make the foam adapt to the needs of various use conditions, it should be allowed to stabilize as long as possible. Roughly speaking, the stabilization time of the foam should meet the following requirements;
1. When used in Portland cement without setting accelerator, the stabilization time should be greater than 60min; the ideal maximum is 3h;
2. When used in fast-setting cement such as sulfoaluminate cement, high alumina cement, iron aluminate cement, fast-setting Portland cement, etc., the stabilization time should be greater than 30min, preferably greater than 60min;
3. When used in magnesium cement, the foam stabilization time should be more than 40min, preferably more than 80min;
4. When used for cementitious materials mixed with a large amount of fillers or active waste residues such as fly ash, the foam stabilization time should also be extended. The larger the amount of filler or active waste residue, the longer the foam stabilization time.
The specific foam stabilization time should be determined through a small test. The principle is that the mold will not collapse after pouring, the pores will not be connected after the formation, and the excessive deformation will not be the principle. The big principle is that the longer the bubble stabilization time, the better.
The larger the bubble diameter, the better, and should be more than 1mm.
The requirements for the pores are the same for the pore size, and the requirements for the bubble diameter should also be the same. Many manufacturers and some experts are misleading to pursue the small pore size of the foam at 0.1mm. In fact, it is because of the physical foaming that if the foam diameter is large, the stability of the foam is poor and the foam concrete cannot be made. The same raw materials and formulations, the same equipment and process, just change the cell diameter. The compressive strength of foam concrete with a cell diameter of 1mm is at least 20% higher than that of foam concrete with a cell diameter of 0.1mm. Therefore, it is wrong to pursue a large bubble diameter above 0.1mm, which is a misunderstanding in the production of foamed concrete and should be corrected.
The lower the foam bleeding rate, the better, avoid milky foams
As mentioned earlier, foam is divided into milky foam with more water and less foam and sponge-like foam with more foam and less water, according to the size of water content. Among them, milky foam is unqualified and inferior foam and cannot be used.
After the foam is produced, it gradually oozes water. Its bleeding consists of two parts:
1. Bleeding of the foam liquid film. This part of the water is secreted from the liquid film, which is the water secreted by the liquid film under the combined action of gravity drainage, surface tension drainage, and liquid film destruction drainage. The thicker the liquid film of the foam, the greater the bleeding; the faster and more bubbles burst, the greater the bleeding.
2. Water between bubbles. This part is the water that does not form a liquid film of bubbles. The worse the foaming performance of the foaming agent and the foaming machine, the more water between the bubbles that cannot form a foam liquid film. They are actually water that doesn't turn into bubbles.
When the bleeding rate of the foam is very high, it will be as thin as the floating juice, flowing chaotically, unable to pile up, and the water in the foam is very large. When this foam is added to the cement slurry, the cement slurry becomes very thin, and the foam is very small. The volume of the slurry is small, and the density of the foamed concrete produced is very high, which does not meet the technical requirements.
Therefore, milky foam is not acceptable. The appearance of the foam that meets the technical requirements should be sponge-like fine bubbles, piled up like white clouds, like bounced cotton, and will not flow chaotically. This foam has very little water content. This shows that its foam liquid film has little bleeding, the foam is not easy to burst, there is little water between the bubbles, and the amount of bubbles is large, and most of the volume is bubbles. It should be emphasized here that the spongy foam must be small bubbles with a diameter of less than 1mm, not large bubbles of several millimeters or even tens of millimeters. Large bubbles are easy to pile up and look like white clouds, but because the diameter of the bubbles is too large, they are also unqualified.
The low bleeding property of the foam is required mainly to ensure the number of bubbles in the foam and the porosity of the foamed concrete, that is, to ensure the density of the foamed concrete.
Foam has no adverse effects on cementitious materials
The cementitious material is the main source of the strength of the foamed concrete, and the addition of the foam can not affect its cementitiousness, that is, it does not produce a negative effect of cementation. This point, not all kinds of bubbles can achieve.
In long-term experiments, we found that many foams hinder the cementation of cement, magnesite and gypsum, which can reduce the strength of foamed concrete. The stability of these foams is very good, it does not disappear for a few hours, the appearance is like a sponge, the bleeding is very low, the density is uniform, and it meets the technical requirements in all aspects, but it is not compatible with the cementitious material, so it cannot be used for production. . This shows that the foam that is qualified in other aspects, such as affecting the strength, is ultimately not technically acceptable.
in nano-building energy conservation and nanotechnology development. We accept payment via Credit Card, T/T, West Union and Paypal. Trunnano will ship the goods to customers overseas through FedEx, DHL, by air, or by sea.
If you are looking for high quality foaming agent, please feel free to contact us and send an inquiry.
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Types of High-efficient Water Reducers
Polycyclic aromatic sulfonates
It has the advantages of low cost and high water reduction rate and has the defects of more serious collapse loss of mixing products. In use, you can add retarding components to compound use or choose such water reducer with sustained-release performance to reduce the loss of collapse and ensure the performance of high efficient water reducer.
Water-soluble resin sulfonates
Mainly for sulfonated melamine resin, and sulfonated ancient code long resin. This kind of water reducer and cement compatibility is better, and other water reducer mixed-use can also maintain good compatibility. Practice shows that this kind of water reducer has a low dosage but high water reducing rate and excellent performance. In a certain proportion, the water-reducing rate increases with the increase of water adding amount. Once the dosage exceeds the critical proportion, the retarding effect on concrete is obvious. Such plasticizer shall not be mixed with a lignosulfonate plasticizer.
Aliphatic series
There are mainly polycarboxylic acid, polyacrylic acid salt. This kind of water reducer is different from traditional water reducer, so it is necessary to understand its mechanism accurately and use it cautiously.
Others
Other types are represented by modified calcium lignosulfonate and modified tannin
When a variety of water reducers are used together, attention should be paid to their mutual influence. In addition to the simple water-reducing performance, the compound water reducer can also have the characteristics of quick setting, early strength, anti-freezing, etc., according to the purpose of use.
Superplasticizer Mechanism
In the process of cement mixing, flocculent particles are attracted to each other due to the existence of molecular attraction, and a flocculation structure is formed. Flocculation encapsulates part of the water used for mixing and reduces the workability of the concrete mixture.
The efficient water reducer has hydrophobic and hydrophilic characteristics, water reducer hydrophobic group directed adsorption on the surface of cement particles, hydrophilic group pointing to the aqueous solution and the formation of adsorption film. Concrete mixing, due to the high-efficient water reducer, directional adsorption makes cement particle surface gay charge, the same, cement particles dispersed to each other, and condensation of flocculant of concrete structure collapse, water was released, supplement the moisture needed for the cement mixing, effectively increase the activity of the concrete mixture, to reduce the effect of the water. At the same time, the surface of cement particles due to efficient water reducer formed by the adsorption film between cement particles and particles contact more mellow, increasing the workability of concrete; The adsorption film also increases the surface area of cement particles and promotes hydration, which is conducive to improving the strength of concrete.
Superplasticizer Supplier
TRUNNANO is a reliable superplasticizer supplier with over 12-year experience in nano-building energy conservation and nanotechnology development. If you are looking for a high-quality concrete superplasticizer, please feel free to contact us and send an inquiry. (sales@cabr-concrete.com)
We accept payment via Credit Card, T/T, West Union, and Paypal. Trunnano will ship the goods to customers overseas through FedEx, DHL, by air, or by sea.
The filling elevation of the foam light soil with different strengths shall be constructed in strict accordance with the design requirements. The anti-seepage geomembrane on the top of the foam light soil subgrade shall be laid under the metal mesh, and the lap joint shall be thermally welded, and the lap width shall not be less than 10cm.
When laying, it should be flattened and tightened to avoid local rolling up. If necessary, U-shaped nails can be used for anchoring. When laying the metal mesh, U-shaped nails should be used for anchoring, the longitudinal anchorage spacing is 2m, and the transverse anchorage spacing is 1.0m. The plane position of the metal mesh should be overlapped and overlapped, the width of the overlap should not be less than 5cm, and the overlap should be bound with plastic buckles and anchored with U-shaped nails.
Before the light soil is poured, according to the boundary conditions of the construction site, the pouring area and the pouring layer are first divided, and the base is checked to ensure that the base is free of debris and water, and that the base elevation meets the design requirements and should meet the following requirements:
1) The top surface area of a single pouring area should not exceed 400m2.
2) The length in the long axis direction of a single pouring area should not exceed 20m.
3) 1.8cm thick wooden plywood is used to support the spacing and joints in the adjacent pouring area. The wooden plywood is a temporary support template and is also used as a deformation joint filling and must not be removed.
4) The thickness of the single-layer pouring layer should be controlled within the range of 0.3-1.0m.
5) The thickness of 0.8m at the top of the light soil subgrade must be used as an independent single-layer pouring layer, and the layer should be poured at one time in each pouring area.
Construction Control Points
1) For the adjacent pouring layers in the same section, when the temperature during the construction period is not lower than 15℃, the shortest pouring interval can be controlled by 8 hours; otherwise, the pouring interval should not be less than 12 hours.
2) The pouring construction time of the pouring layer in a single pouring area of foam light soil should be controlled within 2 hours.
3) It should be poured from one end to the other end along the long axis of the pouring area; if more than one pouring pipe is used for pouring, it can be poured side by side from one end, or the diagonal pouring method can be used.
4) During the pouring process, when the pouring pipe needs to be moved, it should be moved back and forth along the direction in which the pouring pipe is placed, and it is not appropriate to move the pouring pipe left and right; Move to the soil surface.
5) During the pouring process, the discharge port of the pouring pipe should be placed below the current pouring surface as much as possible; in other cases such as the surface being smoothed, the distance between the discharge port of the pouring pipe and the current pouring surface should not be higher than 1.5m.
Care and Maintenance
After the top surface of the light soil pouring area is poured to the design elevation, the surface should be covered with plastic film to moisturise and maintain the light soil roadbed; or non-woven geotextile covering and watering should be used for maintenance. The curing time is not less than 7 days.
Before the top of the light soil subgrade is filled with soil, it is strictly forbidden to drive construction machinery on it; if it is unavoidable in some areas, a temporary protective layer with a thickness of not less than 50cm should be laid at a suitable position or covered with steel plates as a temporary access road for Construction machinery travels.
Connection with other processes
The top improved soil must be constructed when the maintenance strength of the light soil under the same conditions reaches 1.5MPa. During construction, it is strictly forbidden for large machinery such as dump trucks, road rollers, and bulldozers to directly walk on the top surface of the light soil. Paving and rolling are carried out in the forward way of leveling and rolling, that is, unloading trucks and road rollers should unload and walk at the rear end of the leveling machine.
During the rainy season, special measures should be taken to prevent and drain the water and soil, especially to prevent water and soil loss. Measures such as film covering and setting of temporary drainage ditches should be adopted to avoid slope erosion and prevent a large amount of water and soil from flowing to the lower light soil pouring surface for pollution. Light soil.
TRUNNANO is a concrete additives supplier with over 12 years experience in nano-building energy conservation and nanotechnology development. We accept payment via Credit Card, T/T, West Union and Paypal. Trunnano will ship the goods to customers overseas through FedEx, DHL, by air, or by sea.
If you are looking for high quality foaming agent, please feel free to contact us and send an inquiry.
sales@cabr-concrete.com
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