DE3810683A1 - LIGHTWEIGHT CONCRETE BODY WITH A LIGHT EXTRACT OF FOAM CEMENT AND METHOD FOR THE PRODUCTION THEREOF - Google Patents

Abstract

Process for preparing a porous lightweight aggregate from a foamed mineral material. Cement, water and foam from a foaming agent are mixed together in predetermined proportions in such a way that, once the mixture has hardened, its dry bulk density is between 200 and about 600 kg/m<3>. The fresh mixture is then poured into moulds to obtain moulded elements in the form of plates or blocks or the like. Once the moulded elements have dried, they are crushed to produce granules of a granular size not exceeding about 25 mm.

Description

The invention relates to lightweight concrete body with a light addition of foam cement and a method for its manufacture ment according to the preceding claims.

As porous aggregates for lightweight concrete are already ver most diverse materials have been proposed, such as sands, flight ashes, granulated slags and dumps u. like. In addition, one uses the porous, absorbent materials Vermiculite or perlite known from DE-GM 19 58 264 are, or grains of foam glass, which are not absorbent. According to DE-GM 71 30 969 coarse-grained pimples or blown and fired clay pieces with plaster as binder to lightweight panels processed. From DE-OS 25 24 147 it is known lightweight construction Plates made of plaster with a porous aggregate, as such vapor-cured gas concrete fracture and / or Waste material is used, which is crushed into chippings.

However, all these porous aggregates have the disadvantage that they are either relatively expensive and / or there especially must be made, where in nature their raw material finds, as it does with clay as raw material for expanded clay the case is (expanded clay is also hygroscopic and keeps water unduly long), or that it is used in industrial Process as waste or as a relatively rare nature products are incurred and costly for lightweight concrete production and have to be procured costly. Such conditions conditions are in the case of poorly developed and by industry areas far away, for example in the Third world, unacceptable.

The invention is therefore the object of the manufacturer development of a lightweight concrete, essentially cement, lightweight aggregate and water, the Aggregate readily available from anywhere, effortlessly trans portable and inexpensive materials exists or with a the simplest machines and without big costs, energy and Material cost can be produced.

This task is done in a surprising way by the objects of the preceding claims.

The light aggregate according to the invention for lightweight concrete can thus be obtained in the simplest way by producing a foam cement from cement, water and a foaming agent, such as a conventional protein-containing, organic (or synthetic) foam chemical. For this purpose, a foam is added in a conventional manner to a cement Licher amount Licher amount to achieve a density between 200 and 600 kg / m ³ . The foam, in turn, is produced in a closed container from a mixture of about 98% by volume of water and the approximately 2% foam chemical, which is pressed through a nozzle of different length and with the desired diameter, under pressure, whereby the liquid water / Foaming agent mixture when striking the impact body located in the nozzle turned into a white, creamy foam. This foam is added to the cement paste, wherein an increase in volume occurs in that the cement paste evenly envelops the air pores of the foam. After setting of the cement characteristic of a foam cement pore structure is obtained. This known foam cement, which may have a density of 200 to 600 kg / m ³ , hitherto, for example, for absorbing oil films and oil films u. Like. Used, however, to a greater extent for the production of insulating layers of different thickness with and without gradient is set.

This in the simplest way and from cheap and easy foam bodies obtained, the has countless fine air pores, then according to the invention crushed by breaking or cutting, into grains or granules with a maximum size of about 25 mm Diameter. All particles larger than 25 mm will be once more subjected to comminution. It is important for the present invention that all originated in crushing lende Gut, including all accumulated lightweight land, after Classifying as an aggregate for lightweight concrete or as heat insulating light mortar can be used, so that no Waste arises.

To produce the lightweight concrete now be this foam cement grains of suitable and desired size (however, as mentioned with a maximum of about 25 mm diameter) as a slight addition to the water / Cement mixture added. This can be done in any concrete mixer done, or the mixture may be in a concrete tanker before lie and ready for use on site as Ortbeton ge be brought. However, the invention also includes this Mixture fabricated structures, such as hollow blocks, solid blocks, Stones for walls and ceilings, large-sized plates u. like.

The advantages of the invention are obvious: All conven Mixer and the usual moldings or forms can be used, there is a quick binding, what short production times, and the aggregate is a cement-based material, as well as the Zu precipitation-sheathing concrete is the case, so that as a result this material similarity by setting good strength be obtained at low weight. Besides that, it's above mentioned material in contrast to lightweight panels on gypsum basis a much more diverse application in construction in all Climate areas ahead. Cement and water as well as the needed simple machines and tools (silos, mixing machines,  Crushing tools, classifying sieves & more Like.) Are, if not already available, available everywhere, and the extra needed High concentrated foaming agent is easy, cheap and problem los transportable. Since the energy consumption is very small, is also given cost-effectiveness in this point.

The lightweight concrete obtained according to the invention can have between 800 and 1800 kg / m ³ by the foam cement lightweight aggregate Rohdichteklassen, where he has good strength and outstanding thermal insulation properties and is resistant to fire and weathering.

The invention will now be described by way of example explained.

Example 1

For a lightweight concrete for use in the production of block bricks with a density of 1000 kg / m ³ , the following components were mixed:

Cement | 300 kg Natural sand 0-2 mm 490 kg Foam cement granulate 153 kg water 180 kg

example 2

For the production of prefabricated parts for walls as B10 according to DIN 4219 with a bulk density of 1200 kg / m ³ , the following components were mixed:

Cement | 350 kg Natural sand 0-2 mm 610 kg Foam cement granulate 145 kg water 180 kg

Claims (4)

1. lightweight concrete body with a density between 800 and 1800 kg / m ³ , obtained from cement, water, a light surcharge and optionally one or more other conventional additives, characterized in that the light surcharge of foam cement grains with a density of 200 to 600 kg / m ³ and a maximum size of about 25 mm. 2. Light aggregate of foam cement, characterized by grains formed from cement, water and a foaming agent having a density of 200 to 600 kg / m ³ and a maximum size of about 25 mm. 3. lightweight concrete, consisting of cement, water, a light surcharge and optionally one or more other conventional additives, characterized in that the light surcharge by breaking foam with a density of 200 to 600 kg / m ³ to grains with a size of a maximum of about 25 mm is obtained. 4. A process for the production of lightweight concrete structures according to claim 1, characterized in that one breaks foam cement with a density of 200 to 600 kg / m ³ to grains with a size of about 25 mm, these grains added to the other components and the whole in usually mixes and brings or forms.