Polystyrene concrete – a lightweight concrete building material, consisting of various combinations of ingredients that can be summarized as a mixture of cement, porous aggregate granules (polystyrene proper) and special air-entraining additive. For the weighting of polystyrene concrete by increasing density, mineral filler (sand) is added to the composition. This type of concrete is quite widespread, in construction polystyrene concrete blocks are used, facade panels for classic building construction, as a solution for monolithic construction, as well as applicable as an additional means of providing heat and sound insulation.
What should know about polystyrene concrete?
Polystyrene concrete wall blocks have different characteristics, depending on the given density of the polystyrene concrete mixture itself during its production. Therefore, changing the ratio of porous aggregate to cement mortar will affect the direct function that the polystyrene foam blocks will be ready to perform. Based on the mass index in kilograms per cubic meter of volume, there are options for the density of polystyrene concrete in the range from D150 to D600. The characteristics include the ease of production, which allows you to achieve a wide range of densities of the final product, and fit the function of the blocks under the required:
- D150 – D300 – thermal insulation, used as heat insulation;
- D300 – D600 – structural, for creation of bearing and enclosure structures.
As the density index increases, so does the performance:
- compressive strength (class from M 2,5 for D150 to B 2,5 for D600);
- ultimate bending strength (from 0,10MPa for D150 to 0,75MPa for D600);
- coefficient of heat conductivity for dry conditions (from 0,055 for D150 to 0,145 for D600, W/m °С);
- frost resistance (grade from F 25 for D150 to F200 for D600).
Thermal insulation effect is also provided by a special masonry method, using glue instead of cement mortar, which prevents heat loss through the construction joints, the size of which rarely exceed 3 mm in thickness. And pouring polystyrene concrete provides excellent insulation for the floor, corrugated boarding, floors of the building and the roof. Polystyrene concrete meets the high requirements of fire safety:
- flammability group G1 – slightly flammable;
- flammability group B1 – hardly flammable;
- smoke generation group: D1 – weak – for D450-D600, D2 – moderate – for D150-D350.
Directly the pros and cons of polystyrene concrete.
- economic benefit. Polysterene concrete is practically the cheapest heater among the analogues, and allows you to avoid the need for additional insulation foam, foam glass, or mineral wool. Using it as a structural building material does not require additional insulation;
- the low thermal conductivity of the material and tiny interblock joints (when using glue for foam concrete and ceramic tiles) provides reliable insulation and reduces heat loss to a minimum, which also reduces costs in the heating season
- in the case of own production of polystyrene concrete mixture the advantages are the simplicity of its production and low material intensity, which allows reducing the need for mortar by 70%;
- simplified masonry due to the mass and lightweight products from polystyrene at the same time, because the size of a block is equivalent to 17 bricks, and the weight is only 22 kg. This allows you to minimize the use of lifting equipment in the construction process;
- high resistance to aggressive environmental conditions (moisture resistance, low flammability, frost resistance, resistance to mold and mildew) significantly increases the service life of the material up to 100 years, and indicate a wide range of applications;
- high level of sound insulation;
- ecological and sanitary-hygienic safety;
- Does not complicate the internal and external finishing works, easy to handle.
Arise from the fact that the structural properties of polystyrene concrete are related to the cement-sand component.
- low strength mounting fasteners, which requires pre-pouring of concrete in the wall blocks in the place of application of dowels and anchors;
- as a consequence of the above – the complication of mounting doors and windows, intensive use of which leads to the destruction of the material and the sagging of fittings;
- low adhesion to the plaster mixture, which requires additional processing of the walls;
- the impact of high temperatures (the material is not fireproof) and organic solvents contributes to the destruction of polystyrene and loss of properties of the blocks themselves;
- high rates of shrinkage – 1 mm/m.