The self-levelling single layer screed is made with cellular concrete of medium density (with sand), over which the pavement may be bonded directly. The cellular sub-strata can have a density of between 1000 and 1300 kg/m3. It units properties of lightness of the specific weight, thermal and acoustic insulation and important productivity thanks to its being laid in a fluid state.
In traditional double layer screed, the cellular concrete is the insulating sub-strata layer onto which the traditional screed is laid, of which the thickness and the weight is reduced. The lightweight screeds in cellular concrete are used as finishing coat at the level of hydraulic and electrical unit tubing, noticeably improving the thermal insulation and acoustic dampening at tread level, due to its discontinuous structure.
Historically, laying terrace structures was the first application for cellular concrete. Roofs in cellular concrete benefiting from excellent thermal insulation. The density mostly used for such applications vary from 300-400-500 kg per cubic metre which, in the case of a thickness of 10 cm of cellular concrete, corresponds to a weight of only 30-40-50 kg per metre square.
The use of cellular concrete is very practical as a material for filling in the geotechnical sense. In particular, it is useful for filling natural cavities, decommissioned tunnels, culverts, excavations for tubing, subterranean construction work, vaults in historic centres. Thanks to its excellent lightness-strength ratio, cellular concrete allows for filling all cavities without adding excessive weight to the structure. Compared with expanded clay, cellular concrete is the winner in terms of financial convenience, be that for the material or for the cost of transporting to the site.
The use of cellular concrete as an infill material for road excavations in which tubing and conduits are placed, is advantageous due to the excellent process–ability and the simplicity of laying on site. From these properties of cellular concrete, derives a reduction in man hours used and the speed of laying, in that it is self-levelling and auto-compacting. Furthermore, such a solution guarantees reduced or no need for maintenance, thanks to the dimensional stability of cellular concrete, which avoids structural subsidence of the road bed. The versatility of its specific weight allows for not changing the hydrostatic balance of the pre-existing material.
The production of cellular concrete blocks needs no costly plant, furnaces or autoclaves. The blocks are produced with the IBS-08 machine and with special formwork – designed by Isoltech – which allow for creating blocks of various dimensions and for structural needs. The versatility of the units allows also for locating production next to the market of use, reducing transport costs to a minimum, which is on the other hand significant in the case of traditional blocks or autoclaved blocks, which are made in large plants and which require distribution of the finished product on a vast scale.
The acronym 3C represents Continuous Cylindrical Cavity, distinctive of the anti-seismic blocks, and defines a new construction system devised by Isoltech and certified by a report from the University of Engineering of Bergamo. The 3C block in cellular concrete, thanks to its masked shape and the vertical and horizontal cavities, has excellent structural and anti-seismic properties. The revolutionary design of the 3C blocks allows for building more rapidly, dry, without mortar and without the need to build load bearing columns, thanks to the double continuity of the cylindrical cavities which can be filled and strengthened with iron and mortar.