DE19714632A1 - Impervious, setting retarded concrete composition - Google Patents

Abstract

A concrete composition, which allows post-compaction of the concrete surface within 30 hrs. of pouring, comprises (by vol.%) 3-20 (preferably 6-15, especially 9.7-11) cement, 60-85 (preferably 50-80, especially 67-75) aggregate, 0.01-1 (preferably 0.03-0.5, especially 0.05-0.35) additive, 5-30 (preferably 10-20, especially 13.5-17.5) water, 0-1 (preferably 0-0.3) fluidiser and 0-10 (preferably 0-5, especially 0-2.5) flyash making up 100 vol.%. Also claimed is a concrete component and/or structure obtained using the above concrete composition.

Description

The present invention relates to concrete compositions, a Process for their preparation, their use, and liquid dense concrete components and concrete structures thereof, the are particularly suitable as a barrier against water polluting To serve substances.  

The known from the prior art concrete compositions have the disadvantage that the concrete produced therefrom components, concrete structures and the like have too little concrete Degree of compaction, as opposed to as an immediate barrier water-endangering substances to ensure adequate protection In particular, the Herge according to the prior art put concrete components and concrete structures, due to the unzu reaching concrete degree of compaction, too high permeability on their immediate use, for example as a barrier against water polluting substances for building law reasons not allowed without additional surface sealing.

The invention is therefore based on the object, a FDE concrete Composition (liquid-tight concrete after penetration test) for concrete components, concrete structures and the like provide, by means of which a sufficiently high concrete density is achieved so that the resulting concrete components and Concrete structures according to DIN 1045 and / or DIN 4247 already without additional Liche surface seals, usually when dealing with water-polluting substances according to § 19 (g) Water Resources Act be prescribed, are usable.

Due to the obtained higher concrete compaction degree of inventions According to the concrete composition used can be the Construction costs for concrete components and concrete structures that are suitable as a barrier against, for example, water polluting substances serve to significantly lower since the invention is available put concrete components and concrete structures an application additional surface seals no longer necessary makes. In addition, due to the lower production realize faster, faster construction times.

The terms concrete composition, concrete components and concrete construction Works, as used here, also include reinforced concrete.  

The preceding, exemplary list of the use of the Concrete composition is not limiting. Rather, it can be Advantageously use the invention for all applications, in which have a seal against liquid, including liquefied gases, pasty or solid water polluting Substances is required.

This object is achieved by a concrete composition which allows a subsequent densification of the concrete surface within 30 hours after concreting, comprising the components:

• (A) cement;
• (B) concrete aggregate;
• (C) concrete admixtures;
• (D) water;
• (E) optionally, a flow agent; and / or other common fillers; the amount of concrete admixture and / or Flow agent is chosen so that the solidification Beginning of the concrete composition by 3 to 30 hours is delayed.

Advantageous embodiments are set forth in the subclaims leads.

Fig. 1 shows the penetration depths of n-butanol into the surfaces of cores according to Examples 1--4;

Fig. 2 shows the amounts of penetration of n-butanol into the surfaces of cores according to Examples 1--4;

Fig. 3-6 show the influence of a re-compaction on the Eindringmenge according to Examples 1-4;

Fig. 7 shows a schematic representation of the terms in delayed concrete.

Component (A) preferably comprises Portland cement, Portland Cabin Cement, Portland Puzzolan Cement, Portland Fly Ash Cement, Portland Oil Shale Cement, Portland Limestone Cement, Portland Fly Ash Hut Cement, Iron Portland Cement, Tray Cement and / or blast furnace cement. In particular, Portland cement and blast furnace cement for the concrete composition of the invention used. Of the aforementioned types of cement are in particular Portland cement CEM I in the strength class 32.5 R and Blast furnace CEM III in the strength class 32.5, according to DIN 1164-1, preferably usable.

Concrete aggregate (component (B)) of natural rock unbroken and broken dense aggregates from pits, rivers, Lakes and quarries.

The artificially produced concrete aggregates are broken and unbroken dense additions, such as crystalline Blast furnace slag and unground blastfurnace slag as well Boiler slag.

As a concrete aggregate is a mixture of unbroken and / or  broken grains of natural and / or artificial mineral substances. This can be about the same or different sized grains, for example, dense structure consist.

Preferably, concrete aggregate with a maximum grain size of ≦ 32 mm and / or a small grain size of ≧ 4 mm used.

It is advantageous if the concrete aggregate grain, round grain, gravel, Grit, chippings, coarse gravel, metal and / or gravel.

The grading curve of the concrete additive used is preferably so selected, that the slitting line of the aggregate in the Sieblinienbereich between A and C or between U and C, particularly preferably in  Welding line range between A and B, according to DIN 1045. In addition to the aforementioned Sieblinie are of course others Concrete aggregate mixtures usable according to the invention.

As concrete admixture (C) can be added according to the invention concrete additives that extend by chemical or physical action or by both the concrete properties, namely the processability and delay the start of solidification by at least three hours. In particular, delay agents such as Murasit Universal, Murasit Retard 350 and / or Muraplast NN 20, available from MC-Bauchemie Müller GmbH & Co., are suitable as concrete admixtures.

Optionally, a flow agent (E), for example, FM Zentrament F be added to the concrete composition.

In the development of the concrete composition according to the invention has been shown that the addition of retarders Strength properties of the finished concrete considerably increase the instantaneous concrete. By adding a concrete additive, such as Murasite Retard 350 or Muraplast NN 20 The setting behavior of the cement is preferably 3-30 hours delay, whereby a high concrete density level is achieved. In front Abbindebeginn the concrete density is increased by the fact that the Concrete surface preferably recompressed with a vibrating plate becomes.

The recompression has a favorable influence with regard to the reduction of solvent penetration in the fiction, contemporary concrete components / structures, see Fig. 1 to 6.

By adding the concrete additive used in the invention Medium, were achieved at a delay of solidification Beginning of about 30 hours surprisingly found that the resulting due to the heat of hydration temperature increase  of concrete on average by 20%, compared to non-delayed Concrete, d. H. without addition of retarder and superplasticizer (so-called zero Concrete) was reduced. Furthermore, in comparison to not surprisingly found delayed concrete that achieved Compressive strengths when using Kieszuschlag by 26-31% and when using split as a coarse surcharge even by 37-40% the compressive strength values of zero concrete were. Besides, pointed after 7 to 56 days of the invention delayed concrete to one 23-28% increased flexural strength compared to non-retardant concrete (zero concrete). Furthermore, the penetration rates of n-butanol in the present invention delayed concrete on average 27%, reduced by a maximum of 47% and the penetration depths of n- Butanol was compared on average by 10% and a maximum of 15% to non-delayed concrete, reduced. In addition, was observed that the absorption capacity of the concrete according to the invention for water inside a 20 cm thick plate on average by 52%, compared to non-delayed concrete, was reduced.

It is for the optimization of the aforementioned concrete properties advantageous if the time and duration of Nachverdich work and the selected delay time be matched.

In the case of the concrete composition suitable according to the invention the component (A) 3-20 vol.%, preferably 6-15 vol.%, more preferably 9.7-11% by volume; Component (B) 60-85 Vol .-%, preferably 50-80 vol .-% and particularly preferably 67-75 Vol .-%; Component (C) 0.01-1% by volume, preferably 0.03% 0.5% by volume, and more preferably 0.05-0.35% by volume; the Component (D) 5-30 vol.%, Preferably 10-20 vol.% And more preferably 13.5-17.5% by volume; the component (E) 0-1 Vol .-%, preferably 0-0.3 Vol .-%; and fly ash 0-10 vol.%, preferably 0-5 vol.% and more preferably 0-2.5 vol.%; based on the total volume of the concrete composition, wherein the  respective proportions are chosen so that the total volume a total of 100% by volume of the total composition.

A further preferred embodiment of the concrete composition according to the invention comprises 330 kg cement CEM I 32.5 R or CEM III 32.5 according to DIN 1164-1, concrete aggregate maximum particle size d _e ≦ 32 mm grading curve in the area A / B according to DIN 4226 Part 1 and DIN 1045, concrete admixture FM Zentrament F ≦ 1.0 wt .-%, based on the cement weight fraction, and retarder Murasit Retard 350 ≦ 1.2 wt .-%, based on the cement weight fraction.

The concrete composition according to the invention can be in particular advantageous for the production of drip pans, solvents containers, floors, pipes, silos, storage rooms and the like use, in which a high gas and / or solvent tightness is required. In particular, can be from the inventive Concrete composition manufactured concrete components and / or concrete Buildings as a barrier against liquid, including liquefied Gases, pasty, solid and / or other water-polluting substances use.

The present invention is based on the following examples will be explained in more detail.

example 1 Concrete strength class B 25

Cement: 300 kg / m ³ PZ 350 F (Anneliese) Powder content: 375 kg / m ³ AL = L <supplement: oven-dried quartzitic sand and gravel @ Grain group 0/2 mm: 736 kg / m ³ (38%) Grain group 2/4 mm: 146 kg / m ³ (7.5%) Grain group 4/8 mm: 146 kg / m ³ (7.5%) Grain group 8/16 mm: 523 kg / m ³ (27%) Grain group 16/32 mm: 389 kg / m³ (20%) 1940 kg / m ³ (100%) Water: 150 dm ³ / m ³ w / z = 0.5

Additives:

Example Ia

Plasticizer: FM Zentrament F 0.5% of cement weight
Retarder: Murasit Universal VZ 0.7% of cement weight

Example Ib

without plasticizer and retarder  

Example 2 Concrete strength class B 25

Cement: 300 kg / m ³ HOZ 350 L (Dyckerhoff) Powder content: 375 kg / m ³ AL = L <supplement: oven-dried quartzitic sand and gravel @ Grain group 0/2 mm: 736 kg / m ³ (38%) Grain group 2/4 mm: 146 kg / m ³ (7.5%) Grain group 4/8 mm: 146 kg / m ³ (7.5%) Grain group 8/16 mm: 523 kg / m ³ (27%) Grain group 16/32 mm: 389 kg / m³ (20%) 1940 kg / m ³ (100%) Water: 150 dm ³ / m ³ w / z = 0.5

Additives:

Example IIa

Plasticizer: FM Zentrament F 0.5% of cement weight
Retarder: Murasit Universal VZ 0.7% of cement weight

Example IIb

without plasticizer and retarder  

Example 3 Concrete strength class B 25

Cement: 300 kg / m ³ PZ 350 F (Anneliese) Powder content: 375 kg / m ³ AL = L <supplement: oven-dried quartzitic sand @ Grain group 0/2 mm: 736 kg / m ³ (38%) Grain group 2/4 mm: 146 kg / m ³ (7.5%) Grain group 4/8 mm: 146 kg / m ³ (7.5%) Limestone chippings @ Grain group 8/16 mm: 523 kg / m ³ (27%) Grain group 16/32 mm: 389 kg / m³ (20%) 1940 kg / m ³ (100%) Water: 150 dm ³ / m ³ w / z = 0.5

Additives:

Example IIIa

Plasticizer: FM Zentrament F 0.5% of cement weight
Retarder: Murasit Universal VZ 0.7% of cement weight

Example IIIb

without plasticizer and retarder  

Example 4 Concrete strength class B 25

Cement: 300 kg / m ³ HOZ 350 L (Dyckerhoff) Powder content: 375 kg / m ³ AL = L <supplement: oven-dried quartzitic sand @ Grain group 0/2 mm: 736 kg / m ³ (38%) Grain group 2/4 mm: 146 kg / m ³ (7.5%) Grain group 4/8 mm: 146 kg / m ³ (7.5%) Limestone chippings @ Grain group 8/16 mm: 523 kg / m ³ (27%) Grain group 16/32 mm: 389 kg / m³ (20%) 1940 kg / m ³ (100%) Water: 150 dm ³ / m ³ w / z = 0.5

Additives:

Example IVa

Plasticizer: FM Zentrament F 0.5% of cement weight
Retarder: Murasit Universal VZ 0.7% of cement weight

Example IVb

without superplasticizer and retarder (zero concrete)  

Example 5

Compressive strength after 28 days - results of the dice test

For all examples, the values of the 28-day compressive strength became each determined 3 dice. The 28-day Compression Test of the Test specimen was made according to DIN 1048.

For the investigation of the penetration of liquids In each case two drill cores with a diameter of 100 mm were made taken from the concrete specimens of Examples 1-4. The intrusion of n-butanol was according to the directive of the German Committee for reinforced concrete (DAfTtb). For that, the cores were according to the DAfTtb guideline glued in aluminum foil, so that the top and bottom remained free. Subsequently, the test body weighed to ± 0.1 g and then with the manufacturing 2 cm deep in n-butanol. After 72 hours the test specimens were removed from the n-butanol solution and upper removed by dabbing excess n-butanol. The Determination of the penetration rate was carried out by weighing the Specimens.

Subsequently, the test specimens were split, with sulfuric acid sprayed and flattened, reducing the penetration front as a limit A soot blackening was visible and will be determined below could.

Claims (15)

1. Concrete composition which allows subsequent densification of the concrete surface within 30 hours after concreting, comprising the components:

• (A) cement;
• (B) concrete aggregate;
• (C) concrete admixtures;
• (D) water;
• (E) optionally, a flow agent; and / or other common fillers; wherein the amount of concrete admixture and / or flow agent is selected so that the solidification beginning of the concrete composition is delayed by 3 to 30 hours.

2. A concrete composition according to claim 1, wherein the Component (A) 3-20 vol.%, Preferably 6-15 vol.%, Especially preferably 9.7-11% by volume; the component (B) 60-85% by volume, preferably 50-80% by volume and more preferably 67-75% by volume; the component (C) 0.01-1 vol .-%, preferably 0.03-0.5 vol .-% and more preferably 0.05-0.35% by volume; Component (D) 5-30 Vol .-%, preferably 10-20 Vol .-% and particularly preferably 13.5-17.5 Vol .-%; the component (E) 0-1 vol .-%, preferably 0-0.3 Vol .-%; and fly ash 0-10 vol.%, preferably 0-5 vol.% and more preferably 0-2.5 vol.%; based on the total volume the concrete composition, with the respective proportions are chosen so that the total volume of 100 vol .-% total of Total composition results. 3. A concrete composition according to claim 1 or 2, wherein the Component (A) Portland cement, Portland-metallurgical cement, Portland Puzzolan Cement, Portland Fly Ash Cement, Portland Oil Slate Cement, Portland limestone cement, Portland fly ash metallurgical Cement, Iron Portland Cement, Traß Cement and / or Blast Furnace Cement includes.   4. A concrete composition according to claim 1 or 2, wherein the Concrete aggregate (B) from unbroken and / or broken grains with a maximum particle size of ≦ 32 mm and / or in which the concrete Supplement of unbroken and / or broken grains with one Small grains of ≧ 4 mm are present. 5. Concrete composition according to claim 4, wherein the concrete Supplement (B) grain, round grain, gravel, grit, chippings, coarse gravel, Includes metal and / or gravel. 6. Concrete composition according to one of the previous Claims, wherein the concrete surcharge (B) in the wire-line area between A and C or between U and C, particularly preferably in Sieving line range between A and B is. A concrete composition according to claim 1 or 2, wherein the Component (C) is a retarder, preferably Murasite Retard 350, Murasit Universal and / or Muraplast NN 20 includes. 8. A concrete composition according to claim 1 or 2, wherein the Component (E) as flow agent FM Zentrament F. A concrete composition according to claim 7 or 8, wherein the Concrete additive (C) 0.2-1.0 wt .-% and / or the flow agent 0.0-1.0 wt .-%, based on the cement weight fraction. 10. Use of the concrete composition according to one of previous claims 1-9 for the production of concrete components and / or concrete structures that act as a barrier to water hazard liquid, including liquified gases, pasty or solids. 11. Use of the concrete composition according to claim 10 for the production of drip pans, solvent containers, floors, Pipes, silos, warehouses and the like.   12. concrete structures and / or concrete structures available from the Concrete composition according to any one of claims 1 to 9. 13. concrete components and / or concrete structures according to claim 12 with a concrete density grade, whereby the concrete components and / or concrete buildings by at least 5%, preferably between 10 and 47%, more preferably between 27% and 47% reduced penetration of n-butanol compared to concrete components and / or Concrete structures of the same composition, free of Retardants and / or flow agents are. 14. concrete components and / or concrete structures according to claim 12 or 13 with a concrete density level, with the concrete components and / or concrete structures by at least 5%, preferably between 10% and 15% reduced penetration of n-butanol have, compared to concrete structures and / or concrete structures of the same composition, free of retarding agent and / or Are industrious. 15. Process for the production of concrete components and / or Concrete structures made of concrete composition according to one of Claims 1 to 9, wherein the components A to H, optionally with the addition of other fillers such as fly ash as a mixture is applied, and the concrete before Abbindebeginn within up to 30 hours after concreting, after wherein a concrete density level is reached, wherein the concrete components and / or concrete structure compared to a reduced Hindringmenge n-butanol according to claim 13 and / or a reduced penetration depth of n-butanol according to claim 14.