Mastic asphalt
Mastic asphalt is a building material and belongs to the asphalt group . It is a mixture of fine and coarse aggregates and bitumen that can be poured and painted during installation. Therefore, no compaction work is necessary when using mastic asphalt. Mastic asphalt is used as road surface , as floor covering and for waterproofing .
Technical characteristics
| Requirements for mastic asphalt according to TL Asphalt-STB 07 | ||||||
|---|---|---|---|---|---|---|
| designation | MA 11S | MA 8 p | MA 5 p | MA 11 N | MA 8 N | MA 5 N |
| Coarse aggregate in mass% | 45-55 | 40-50 | 35-45 | 45-55 | 40-50 | 35-45 |
| Filler (stone flour) in mass% | 20-28 | 22-30 | 24-32 | 20-28 | 22-30 | 24-32 |
| Bitumen content at least in mass% | 6.8 | 7.0 | 7.0 | 6.8 | 7.0 | 7.5 |
| Minimum static penetration depth in mm | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 |
| Maximum static penetration depth in mm | 3.0 | 3.0 | 3.0 | 4.0 | 4.0 | 4.0 |
| Increase in penetration depth in mm | 0.4 | 0.4 | 0.4 | 0.6 | 0.6 | 0.6 |
| dynamic penetration depth in mm | must be specified | |||||
| Hardness classes of mastic asphalt according to DIN / EN 13813 | |||
|---|---|---|---|
| Hardness class | Penetration depth in mm for a punch cross-section | ||
| 100 mm² | 500 mm² | ||
| 22 ° C - 5 h | 40 ° C 2 h | 40 ° C 0.5 h | |
| IC 10 | ≤ 1.0 | ≤ 4.0 | - |
| IC 15 | ≤ 1.5 | ≤ 6.0 | - |
| IC 40 | - | - | > 1.5 to 4.0 |
| IC 100 | - | - | > 4.0 to 10.0 |
Applications
Mastic asphalt is predominantly (50% in Germany) used in building construction and industrial construction as mastic asphalt screed and, in conjunction with bitumen welding sheeting, as building waterproofing (for example on parking decks and courtyard cellar ceilings as well as on earth-covered structures such as underground garages).
Another important area of application (about 25%) is the use in road construction. There, mastic asphalt is mainly installed as a top layer on federal motorways. In addition to this use, the building material can also be found in bridge construction as well as in trough and tunnel structures as part of the sealing with bitumen welding sheets or liquid plastics as a sealing layer. Here, too, the proportion is around 25%. The proportions in the areas of application fluctuate slightly each year depending on the respective order situation.
Road surface
Since poor compaction after paving is a major cause of impairment of the durability of asphalt pavements, the use of mastic asphalt in asphalt road construction is recommended. In road and bridge construction (for example in Germany according to ZTV Asphalt-StB) the mineral mixtures 0/11, 0/8 and 0/5 are common. The mineral mixture is mainly used 0/5 in foot and bike path construction. Mixtures of 0/8 and even 0/5 mm are also used on federal motorways for noise-optimized surface layers. In the meantime, mastic asphalts, usually with the largest grain size 5 mm, are also used as a sealing layer under open-pored asphalt; The task of the mastic asphalt here is to protect the asphalt layers underneath from water ingress from the open-pored asphalt. The stability is primarily controlled by the hardness of the mortar and thus by the hardness of the bitumen. The grain size plays a subordinate role for the stability.
Road construction bitumen according to DIN EN 12591, z. B. bitumen 30/45 and 20/30, or polymer-modified bitumen of comparable hardness are used. The proportion of binding agent in mastic asphalt in road construction is 6.5 - 8.5 M.% (with conventional asphalt: 5.5 - 7.7 M.%). When using road construction bitumen, natural asphalt is partially added to the asphalt mixture (1 to 2%). In the past few years, the processing temperature has been reduced from the usual approx. 250 ° C to a maximum of 230 ° C. This is made possible by special binders or additives, which allow the mastic asphalt to be processed at temperatures around 20 ° C lower than was previously the case.
Mastic asphalt is particularly stable and resistant to aging. To increase the fine roughness of the surface and to improve the initial grip, mastic asphalt cover layers in road construction are rubbed or scattered with sand or gravel with grain sizes 2/5, 2/4 or 1/3 mm.
A special form of mastic asphalt is the so-called Olympic mastic . This is a layer of mastic asphalt about 2 to 3 cm thick, into which about 15 to 20 kg / m² of heated pebbles with a grain size of 2/4 or 4/8 are scattered and light be rolled in. In this way, attractive mastic asphalt surfaces can be designed for park paths, for example. The Olympic mastic was developed during the construction of the outdoor facilities for the Olympic Center in Munich in 1972.
Flooring
Mastic asphalt screed is a bitumen-bound screed made of chippings , bitumen, sand and rock dust, which is either used indoors as a sub-layer for a floor covering or refined several times to create a matt to glossy top floor. It can be produced without thresholds and joints and represents a waterproof, cavity-free and practically water-vapor-tight floor.
features
The building material has a low thermal conductivity and is well suited for thermal insulation. Because of these properties, it is perceived as pleasant and warm to the feet. Thanks to its high internal damping (28 times higher than that of concrete) and low structure-borne sound conductivity, it reduces the transmission of impact sound to other components. In combination with other insulation systems, impact noise can be reduced by up to 33 dB (A).
Furthermore, it is possible to reduce stresses from temperature fluctuations or slowly occurring building movements without cracks thanks to its natural elasticity. Because of its visco-elasticity, it is abrasion-resistant and can handle heavy vehicles. With regard to fire protection, mastic asphalt screed can be classified as flame-retardant, as it consists of 90% rock. Based on existing reports, use on escape routes is permitted (fire protection class B-s1 according to EN 13501-1 or B1 according to DIN 4102-4).
Furthermore, its recyclability and resistance to acids and alkalis are advantageous. In addition, the installation time for mastic asphalt screed is extremely short: after two to three hours, this screed has reached its final strength and can be further sanded or processed. The installation height can be dimensioned extremely low, so mastic asphalt screed has a minimum nominal thickness of 2.5 cm (with area loads ≤ 2 kN / m²) with a suitable substrate.
Since there is no hydration (as is the case with cement screed, for example), no moisture is brought into the structure during installation. This is particularly advantageous when renovating old buildings . The problem, however, is the risk of deformations as a result of the action of concentrated loads.
Areas of application
Mastic asphalt screed is used in the construction of commercial and public objects and offices as well as in private residential construction. It is also used for a continuous look inside and out for flowing rooms and terraces, in bathrooms as a built-in shower tray and as wall cladding. In the renovation of old buildings, it is used to increase footfall sound or thermal insulation and to create a barrier layer against rising damp. It can also be used as a heating screed .
Mastic asphalt screeds in structural and industrial construction are produced in accordance with DIN 18560 "Screeds in construction". The mastic asphalt compounds must comply with DIN EN 13813 "Screed mortar and screed compounds - properties and requirements". Mastic asphalt screed compounds for heated and unheated rooms are made with hard bitumen, which is harder than road construction bitumen. Road construction bitumen is also used for paving outdoors. Mastic asphalt screeds can be covered with all floor coverings. In industrial plants, mastic asphalt screeds are mostly used directly, i.e. H. used without further floor coverings. Mastic asphalt screeds are also increasingly used directly in modern architecture - but mostly colored or sanded. Sanded mastic asphalt can develop an effect like a conventional terrazzo if the existing pores are filled appropriately and the sanding is carried out finely enough in several stages. The only thing that stands against the use of mastic asphalt as a sanded floor is its low resistance to oils, fats and solvents, which, however, is not relevant in rooms with normal loads.
seal
At the processing temperature (maximum 230 ° C) there is a small excess of bitumen in the mastic asphalt due to the higher coefficient of thermal expansion of bitumen. This results in the spreadability. After cooling, the void contents of the granular mixture are completely filled with bitumen. Mastic asphalt is therefore practically watertight and free of voids (according to DIN). However, spherical pores always remain in the material, but they do not affect the tightness.
Mastic asphalt is therefore used on bridges, in troughs and tunnels (see, for example, ZTV-ING) and in civil engineering as a component of seals (see DIN 18195 "Structural seals ").
Norms and standards
- Germany
- ATV / DIN 18317 - traffic route construction works - pavement layers made of asphalt
- Additional technical contract conditions and guidelines for the construction of asphalt road surfaces (ZTV Asphalt-StB 01)
- Technical delivery conditions Asphalt-STB 07
- DIN / EN 13813 - Screed mortars, screed compounds and screeds - Screed mortars and screed compounds - Properties and requirements
- ATV / DIN 18354 "Mastic asphalt work"
- DIN 18560 - Screeds in construction
- Austria
- ÖNORM EN 13108-6 - Asphalt mix - Mix requirements - Part 6: Mastic asphalt
- OENORM EN 12970 - Mastic asphalt and asphalt mastic for waterproofing - Definitions, requirements and test methods
- Switzerland
- SN 640440 - mastic asphalt, mastic; Concept, execution, requirements for the installed coverings
- SN 640441 - asphalt - mastic asphalt; Mix requirements
- SIA 283 - Mastic asphalt for waterproofing, protective and wear layers as well as for floor coverings and screeds
See also
Web links
- Action group mastic asphalt in building construction
- bga - Advice center for mastic asphalt application eV
- Technical information on mastic asphalt
Individual evidence
- ↑ Further information on the Olympic mastic ( memento of the original from October 18, 2012 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 673 kB).
