DD298872A7 - SLAB CARBONDS FOR TRAFFIC SURFACES - Google Patents

Abstract

The invention relates to building materials for Verkehrsflaechen and Grundungen using industrial products. The proposed building materials are particularly suitable for base courses and load-bearing layers of Verkehrsflaechen, but also for reasons of other building structures. The essence of the invention consists in new formulations, wherein 72 to 96 * converter steel slag and 4 to 28 * defined finely granulated waste materials of steel and power plants are mixed. As immediate technical effects are in these new mineral building materials especially without the use of synthetic hydraulic binder vorzuegliche structure and strength development in the course of static and dynamic loads of the corresponding structural objects and under road conditions due to initial hydration and kinetic stability physical parameters that allow immediate use to determine. {industrial seizure product; Converter steel slag; Accumulation material, finely granulated; Building material, mineral; Traffic area; Road condition; Founding; Anfangshydratation; Stability, kinetics; Burden; Structure development; Strength development}

Description

compound, the relationship 0.1 <β <0.5

on the proportion of particle sizes g 1 mm of the total mixture is relevant, the particle size distribution of the converter slag

- with homogeneous particle size distribution after the power function

with x> 0.2 for max d = 32 mm and χ> 0.25 for max d = 16 mm

he follows '

in the case of inhomogeneous particle size distribution, the proportion of the

Grain size group d S = 1 mm of the converter steel coating in the mixture and the particle size distribution of the additives contains a minimum proportion of 80 wt .-% of the particle size d <0.25 mm and 40 wt .-% d <0.063 mm

 2. Building material according to claim 1, characterized in that at a free lime content of the building material mixture of greater than 8 Ma .-% by the particle size distribution, a residual pore space of 5% and more is specified.

Field of application of the invention

The invention relates to a building material for traffic areas and foundations. The proposed building material is preferably suitable for base courses and load-bearing layers.

Characteristic of the known state of the art

The use of slags and ashes as a building material component is known. For example, blast furnace slags have been used for construction purposes for some years, while the practical use of steelworks slags is quite problematic because of their different chemical composition. But even today there are some more or less useful solutions.

These include proposals to use waste slag from LD steelmaking (Linz-Donawitz process), whereby steel from steel iron is produced in the converter by oxygen refining, and from the Siemens Martin process, for example, in road construction. It has already been possible, by a defined combination of SM slag containing the mineral monticellite (Fe monticellite) and fly ash of a basic character, which has a low SO ₃ content, to develop a building material which, without the use of cement, has compressive strengths of 30N / mm ² (DD-WP CO 4 B / 277756-1).

Furthermore, according to DE-AS 1,293,072 known, the main components blast furnace slag and / or natural stone of a mineral concrete for use in road construction deposited Siemens Martin and / or converter slag with grain sizes in the range of 0 to 12 mm to add, the free lime content this slag is substantially rinsed or chemically bound. In this building material mix, the proportion of steelworks slag is limited, in particular because of the damaging effect of free lime.

In this case, the grain fraction of 0 to 12 mm can be fully realized by means of SM and / or converter slag, but this requires a costly treatment of this steelworks slag by vibrating crushing, impact mill crushing, classification and longer moist storage. Otherwise, "lime rubbing" will occur in the road surfaces.

According to DE-AS 1,915,551, ground Siemens-Martin slag with a maximum grain size of 3 mm can be used for the production of a sealant for hydraulic structures. Here you put this slag hydraulic lime and 25 to 35% water to a pumpable mass for the sealing of z. B. soles and embankments of canals, rivers and ponds. In this case, the SM slag is brought to a lime content of more than 30%, preferably over 00% (the percentages being based on the solids content of the sealant.) Alternatively, the addition of clay powder, sodium chloride, water glass, aluminum sulfate and / or trass is provided.

A fine-grained binder of granulated blast furnace slag and steelworks slag for by heat treatment and / or steam curing components to be produced is described in DE-AS 2,040,484. This binder contains 60 to 40% by weight blast furnace slag and 40 to 60% by weight steelworks slag. Of all steelworks slags, the SM and / or LD slag are preferred as exciters. 5 to 10% by weight of gypsum or anhydrite may be added to the mixture. The hydraulically reactive component is the blast furnace slag in the form of granulated blast furnace slag because, as is known, SM and LD scrubbers are not hydraulic after quenching.

A concrete mix with converter slag of two different classifications is the subject of Japanese Patent 55-27026. Thereafter, one cubic meter of this building material mixture contains 376 kg cement, 1187 kg coarse and 745 kg fine converter slag, 65 kg of a SiO ₂ -rich additive and 210 liters of water.

Also according to the SU-copyright 1074.842 14 to 15Ma .-% cement are required to produce a wear-resistant concrete using converter and blast furnace slag. In this building material mixture, the largest grain diameter of the converter slag is 20mm and that of granulated blast furnace slag is bmm. At the same time here the use of dead CaO-rich residues of the soda industry and alternatively fired SiO ₂ -rich rock. Both additives are ground up very finely.

On the other hand, many proposals are known to utilize the industrial waste product ashes useful. In this context, it has been found that silica-rich and low-sulfur ashes are quite well suited to the construction and building materials industries. These include primarily some electrofusion snacks with an SiO ₂ content of 45 to 55 Ma .-%.

Sowirdz. For example, US Pat. No. 4,050,950 describes a construction material for the protection of pipelines that is made of Portland cement, fly ash, aggregates and water. To produce this low-pore building material so-called Trenton Channel Fly Ash from Jer coal combustion is used, which as a dry ash 21% Fe ₂ O ₃ , 25% Al ₂ O ₃ , 1% MgO, 1.8% CaO, 0.4% Na ₂ 0 , 1.5% K _2, 0.1.3% TiO ₂ and 48% SiO ₂ . This fly ash is thus characterized by high hydraulic factors, the pH being 10.4.

The disadvantage of the solution according to US Pat. No. 4,050,950 is that the building material proposed here does not reach the compressive strengths of ordinary concretes, which is not least due to the choice of additives used.

According to DE-PS 932,360 a method for producing a building material from ashes of all kinds, in particular from hard coal fly ash, which contains silica and alumina as the main components, is known.

Water glass is part of a lime and cement containing cement. It is essential in this description of the invention that the crude ash is added to the admixing of the binder sulfuric acid; whereby the existing in the crude ash, the strength of the binder impairing components are harmless, so that when using a so pretreated material moldings should always be produced with the same strength properties. However, the cement content of the binder is the decisive factor.

This description of the invention includes only a general technical teaching. Avenues for the lack of exact formulation information is the reproducibility or an effect-safe industrial applicability not given.

According to DE-PS 934.396 .vird a building material from Qipsreicher ash (lignite fly ash) and water is proposed depending on the purpose of the binding force or their adhesion-enhancing substances such as water glass, caustic soda, soda, alum, paint, Zellim odor sulfite waste liquor are added. The illustrated building material variants are suitable as mortar, PuU, insulating against rising damp and for the protection of easily combustible components. Likewise, it can be used to make useful layers for floors. When adding fillers to the ash-water mixture, it is also possible to produce lightweight components by molding and pressing.

In road construction, the ash-water mixture according to DE-PS 934 396 with the addition of tarry substances at most useful as a topcoat for light traffic, the corresponding building material mixture to produce only at the installation by means of dry ash and is to be processed immediately thereafter.

According to the SU-copyright 491.759 a so-called heap ash mixture of grit and sand fractions containing granulated fuel slag and fly ash is used for the U.iterbau of traffic areas.

The cementless building material mixture in question consists of 80 to 90% by mass of this ash-slag mixture, 2 to 10% by mass of lime, 0.2 to 1.0% by mass of calcium chloride and 7 to 15% by mass of water. However, the feature that 35 to 85 mass% of fuel slag and 15 to 65 mass% of fly ash are contained in the seizure product is insufficient to indicate the immediate technical effects of the invention proposal. Thus, because of the lack of chemical compositions of the slag and ash to be used, there is a lack of reproducible disclosure, which is why the functionality or industrial applicability is not guaranteed on a regular basis.

Ashes are also recycled according to DD-PS 26,756 in a method for short-term sealing and controllable plastic stiffening of soil types, after which u.a. Mixture of ash and sewage sludge, which are acidic or alkaline and weak or non-binding, using water with water glass and / or hydrating clays or bentonites, which are finely ground or slurried, optionally with the addition of alkaline salts such. As potassium or sodium carbonate, are mixed in order to obtain in a definable time a controllable depending on the dosage of the mixture plastically stable mass, in particular for the sealing of dykes, dams, channels u. Like. Is suitable. This building material mix stiffens * very quickly and is insoluble in water. This hydrates, which cause a high density and a very consistent cohesion of the mass, which are given high frost resistance and great anti-slip. In the solution according to DD-PS 26.756, the immediate technical effects are that the liquefied and hydrated by the added or existing salts and water clay minerals (montmorillonite, etc.) a complete sheathing of nichthydationsfählgen, non-clay components of to be refined Mixtures form, similar to the cement, the aggregates wrapped in concrete, but in the present case, a plastically stable mass after the stiffening arises.

It is important here that the wettable surface of the grains to be coated is as large as possible.

When natural clay is used in this process with the yield point between 0.4 and 0.6, about 15 to 24% clay is required to achieve the effects shown.

DE-PS 1,127,822 includes a method for the production of roadbeds and base courses, wherein 10 to 30 parts by weight of silicon or aluminum-containing "raw" fly ash with very low binding properties, 70 to 90 parts by weight of a high degree of fineness and 2 to 9 parts For example, only half a year after completion of the hardening reaction, only half of the compressive strength resulting from the complete hardening reaction is present after one year Lime on the water retention capacity, since the lime interacts only intermittently with the other components of the mixture.Also, it is known that in the converter steelmaking process, in contrast to the Siemens Martin process, no complete dissolution of the lime, i. that is, no complete melt equilibrium is achieved. In the solidified converter Stahlwerksschlacko is therefore a proportion of CaO in a dispersed arrangement.

The well-known disintegration of converter steelworks slags is mainly attributed to the oxidation and hydration of the abundant Wüstitphase. Therefore, this slag is not suitable as an aggregate for heavy concrete. Converter steel slags according to the LD ancestor sound differ from Siemens Martin slags in their mineralogical constitution as well as in the distribution of minerals in the solidified mass. These differences are procedural and dependent on the use of the raw materials. In "Metallurgy and Materials Technology" by Zimmermann and Günther, VEB Deutscher Verlag für Grundstoffindustrie, 1977, this difference is also illustrated by thermodynamic analyzes.

Siemens-Martin-Schlacke exists as a mineral mixture and is used for the production of mineral concrete base courses. The granulometric resistance is detected by decomposition analyzes. It forms an important condition for the long-term frost resistance of the unbound base courses. The long-term previous storage of the Siemens Martin slags contributes by flushing water-soluble ingredients and by hydration of coarse hydrated inclusions with the resulting demolition of some bodies that occur in the mineral concrete no local disturbances. These processes are completed after one to two years of storage. The Kornhaufwerk has danacch grain structures, which remain in the course of the technical application. On the other hand, because of the mineral distribution in the grain, in particular the distribution of finely dispersed species and westsite under the influence of weather, the grain structure of the converter steel slags is subject to a constant shell-like disintegration, which only comes to a standstill if there are no dispersed inclusions in the grain husk in the residual grain In contrast to the Siemens Martin slag, in which only a small proportion of the grains are completely blown up by hydration of constituents, all the grains of the LD slags are subject to the shell-like decomposition mechanics proceeding from the outside in. Steam treatments and the storage of Converter steel slags in a water bath show the continuous continuous decay process, which is demonstrated by the time-dependent degree of fineness or the degree of the Komzerrümmung (see diploma thesis by Pohl and Bergmann "Studies on the application of convert Cremation in road construction ", Engineering College Cottbus, 1985).

The dumping of slags can also be replaced by treating the slags with acids. Due to the differences shown in the effects of partial hydration, this technology has some significance in Siemens Martin slags in that grain fragmentation of individual grains is accelerated by hydration of the coarse inner inclusions. As a precondition, as a result of the dispersed arrangement of expanding constituents of converter steel slag granules, this process can only come to a standstill when the shell-like decay has been completed and a particle size has formed which corresponds to the spacing of the dispersed expanding substances. The particle size distribution of the decomposition product achieved in this way is not suitable for technical products of road construction with required high initial stability and frost resistance because of the high degree of fineness.

In summary, the shortcomings of the known solutions are that they do not allow any economically significant utilization of converter steel slags by the LD process, also in combination with other substances, without using valuable synthetic binders and expensive aggregates.

Thus, a disadvantage of the prior art is that layers of traffic areas using converter steelworks slag may not be made sufficiently rigid, rigid, and usable immediately after their manufacture. Under these conditions, there is no solution that is suitable for high-quality mineralized compact layers with the combined function as a carrier and top layer, as a top layer on flexible base courses and as a base course in road constructions and for foundations.

Object of the invention

The object of the invention is to develop a high-grade mineral building material for traffic areas, preferably roads, but also for foundations of other structures using industrial products which can be produced without industrially produced synthetic binders. In this case, a long service life of the corresponding structures and over the prior art, a reduction in the cost of reproduction should be achieved.

Explanation of the essence of the invention

The object of the invention is to accumulate Konvertei steel slags with suitable mineral accumulation materials so composed that without the addition of cement and / or other synthetic hydraulic binders mineral building materials arise, characterized by high initial stability, by rapid development of high bending tensile strength and by a long-term positive structure - and Festigkei skinetik. Cracks due to temperature and traffic-related stresses and disturbances of the structure in road surfaces are excluded. According to the invention, this object is achieved in that 72-96Ma .-% converter steel slags, which are the main chemical constituents

15-40Ma .-% Fe and FeO _x FeO 35-55Ma .-% CaO, of which 3-18 Ma .-% CaO _(te | Fe ₂ O ₃ 7-18Ma .-% SiO ₂ CaO, of which 0-8 Ma .-% CaO _f "i 1-6Ma .-% MgO SiO ₂ 2-6.5Ma .-% MnO _x MgO 0.3-2% by weight Al ₂ O ₃ MnO 1- 2.5Ma .-% P ₂ O ₆ Al ₂ O ₃ , and 4 to 28Ma .-% ash or dusty SO ₃ 0-17Ma .-% & -15Ma .-% 18-65Ma .-% 6-45Ma .-% 0,5-12Ma .-% 2-15Ma .-% 2-25Ma .-% 0-15Ma .-%

contain.

The converter steel slag has a homogeneous particle size distribution according to the power function

^vl maxd ^;

with χ> 0.2 for max d = 32 mm

and χ> 0.25 for max d = 16 mm.

The finely granulated (dust-like to fine-grained) waste material of the steel and power plants has a particle size distribution for which

a minimum percentage of

80% by weight of the grain size d <0.25 mm and 40% by weight of the grain size d <0.063 mm

is present.

Provided that the free lime content of the new building material mixture is greater than 8% by weight, the grain size distribution is adjusted so that a residual pore space of greater than or equal to 5% is provided. The ratio β of the existing in the building material mixture mass of the fine-grained accumulating material to the total proportion of grain sizes with d less than 1 mm on the building material mixture according to the above chemical composition is in the range

0.10 <β <0.50.

When using inhomogeneous grain distributions with default grain apply the same conditions for the fine-grained added accumulating materials, and it is generally necessary that the converter steel slag contains a grain fraction, which ensures the necessary for the realization of β proportion of the grain size group d less than or equal to 1 mm. The structural and strength development of this new building material recipe for slag beds, whose efficiency depends not only on the mixing ratio of the components involved from a chemical point of view, takes place over a long period of time, but is given by initial hydration and kinetic stability initial usability in the short term. In contrast to conventional building materials, which consist of inert aggregates with suitable particle size distribution to fulfill the task of ensuring a minimum gap content through maximum packing density of the grains of the aggregates, and a binder, which has to fulfill the task, the inert grains of the aggregates by solid To connect bridges with technically effective adhesion to the aggregate grains, the binder used to some extent

as an autonomous component of the concretes has a hardening kinetics independent of the additives, the essence of the invention is characterized in that all components of the building material are involved in the first phase of their existence in the mixture physical bonds and friction and due to their arrangement and shape large deformation resistances to create.

In the development phase of the building material to a heterogeneous multidisperse system with fixed bonds all building material components are involved in the production of reaction products. The particle size distribution is not organized according to the conventional goal to achieve a maximum packing density, but it should cause the process of the implementation of the ingredients over a long period as possible. The packing density is therefore in the initial constitution in contrast to S. d. T. not maximum. Only requirements for the minimum size of the deformation resistance are to be met as a sufficient condition.

In this connection, the disintegrating property of converter steel slag, which is otherwise referred to as disadvantageous, exerts an important function. It consists in the fact that the shell-like disintegration, progressing from outside to inside, produces not only a constant availability of slag particles with a large specific surface during the process of the development of the building material, which produce new reaction products with the fine-grained ashes and slags in the mixture.

This process is facilitated by providing the lime-rich fine-grained ashes and slags in the mixture with a pH greater than 11.5. In comparison, the KSS have a pH of about 8.

In this way, the long-term structural development is both the long-term positive strength kinetics guaranteed and the ability, Strukturella disturbances during the long-term evolution process, such as micro-cracks caused by mechanical effects, in conventional building materials due to the completed structural development at an early stage such as at Cement concrete leads to a negative strength development, to compensate.

The specified conditions for the construction material composition ensure that the effects described occur eir.

embodiments

The invention will be further described with two examples.

According to a first variant converters slag of grain size 0 to 32 mm, from the fractions 0 / 2.2 / 4.4 / 8, 8/16 and 16 / 32mm according to the particle size distribution

£ = 0.3

is composed, a main chemistry of

16, iMa .-% FeO

7.1 Ma .-% Fe ₂ O ₃

48.1% by mass of CaO, of which 7.5% by mass of CaO ₍ "i

14.0 mass% SiO ₂

1.0% by weight of MgO

3.5% by weight of MnO

0.8% by weight of Al ₂ O ₃

and electric furnace refining slag, which meets the requirements of the above-mentioned mineral waste materials, their Chemismus by

9.42Ma .-% FeO

5.19 Ma.% Fe ₂ O ₃

58.40 Ma .-% CaO

7.70Ma .-% SiO ₂

2.47Ma .-% MnO

3.15 Ma .-% Al ₂ O ₃

1.69 Ma .-% P ₂ O ₆

0.80 Ma .-% SO ₃

is mixed in a compulsory mixer. The ratio β is 0.18, and thus the proportion of electric furnace refining slag with d = 0 to 1 mm is 5 mass%, and the proportion of convertible slag with d = 0 to 32 mm is 95 mass% of the building material dry mixture.

After preparation of the mixture in the compulsory mixer by means of dump trucks transport to the installation site, where with a 12 tonne vibratory smooth-shell roll layers of 100 to 200mm thickness or with a corresponding 25-ton roller layers of 150 to 250 mm thickness are compacted.

The building material then develops under road conditions, d. H. Under tension conditions, surprisingly without the use of hydraulic binders the above-mentioned excellent structural and strength properties, which lead to new advantages over the prior art.

The same effects and effects can be achieved by applying the new Baustofempfzeptur foundations of corresponding structures in the field of the entire construction industry.

1.1 In a second case, finely-granulated waste (28% by mass) is a calcareous ash, which is the main chemical constituent

7.95Ma .-% Fe ₂ O ₃

19.50 Ma .-% CaO

25.70 Ma .-% SiO ₂

1.50 Ma .-% MgO

9.14 mass% Al ₂ O ₃

6.90 Ma .-% SO ₃

and whose phase inventory is characterized by 85% glasses and mixed phases, mixed with 72% by weight converter steel slag of the particle size group 0 to 32 mm with homogeneous distribution of the particle sizes.

The production of this new building material is similar to the production of Zementboton. The layers of road constructions produced using this recipe are passable after being compacted without tire vehicles leaving any traces on the freshly prepared layer.

With increasing load the load capacity of the road construction is increased from the building material according to the invention.

During this process, no tracking can be detected. This advantageous effect is caused by the high initial stability of the compacted layer and the strength kinetics of the building material.

The special possibilities of the application of the invention result from the ability of the building material to be able to compensate disturbances of the microstructures and macrostructures by mechanical influences over a long period of time.

The invention is therefore particularly suitable for dynamically stressed upper base layers for cement concrete topcoats, for highly stressed Baustraßen, factory roads and military roads, for compact wearing surface layers in urban and rural road construction, for parking areas and for foundations of residential and community buildings.

The specific advantages of the application of the building material is that occur in particular dynamically stressed layers and coverings in road structures due to the long-term positive structural and strength kinetics of the building material no loss of property capacity in terms of their sustainability, the life of the components and structures due to functionally predetermined and controlled, and road constructions can be produced that are independent of the number of repetitive driving processes.

The advantage of using the building material is also due to the fact that the required for the preparation of the mixture component water is not added for the sake of hydration of fabric components, but only to achieve the required for the technology property processability, without technically relevant adverse effects in variation Enter the water content.

Claims (1)

1. building material for traffic areas and foundations using steel slags, characterized in that it consists of 72 to 96 based on the respective building material dry mixture Ma .-% converter steel slag, as the main chemical components have, and 4 to 28 based on the respective building material dry mixture Ma .-% fine-grained accumulating materials of steel and power plants contains, the fine-grained accumulation materials are from the main chemical components 5-15Ma .-% Fe ₂ O ₃ 18-65% by weight of CaO, of which 0-8% by weight of CaO ₃ 6 ^ 45Ma .-% SiO ₂ 0.5-12Ma% MgO 2-15Ma .-% MnO 2-25% by weight Al ₂ O ₃