DD253608A1 - HIGH-STRENGTH POLYESTERBETON - Google Patents

Abstract

The invention relates to the development of a polyester concrete, which has a high strength, tightness, aggressiveness and abrasion resistance by the composition according to the invention and is thus particularly suitable for highly stressed engineering constructions of mining, the chemical industry and power plant construction. It is the object of the invention to reduce the amount of resin used in polyester concrete, the object being to achieve, compared to the prior art, significantly improved mechanical and physical properties, such as higher strengths. According to the invention, this is done by using an active aggregate mixture with low void volume, which is bound with minimized resin content of 4.5 to 7 wt .-% of the total mixture and addition of methacrylic silane as a primer and a polyester concrete with compressive strengths of 100 to 140 MPa, to Slimming test specimens at l2, with a follow-up of five hours at 353 K of 120 to 150 MPa.

Description

Cobalt accelerator (1%) with 1% by weight,

based on the binder content is used, and this mixture additionally 3 to 3.1 wt .-%, based on the aggregate content of a 2% alcoholic methacrylic silane solution as a primer and 3 wt .-% distilled water as a wetting agent in the preparation was attached.

2. High-strength polyester according to item 1, characterized in that at a binder content of 4.5 to 5.5Gew .-%, based on the total mixture, the binder 5Gew .-%, styrene contains as a plasticizer.

3. High-strength polyester concrete according to item 1 and 2, characterized in that this produced with a binder content of 4.5% to 7 wt .-% of the total mixture, introduced into molds for special components at high compression and postcured for five hours at 353K, has a compressive strength of 120 to 150 MPa, at a slenderness level of λ = 2.

4. High-strength polyester concrete according to item 1 to 3, characterized in that the selected aggregate mixture coated only with a thin film of unsaturated resin, hardener, accelerator and adhesion promoter, compacted by vibration and / or pressure, aufeinanderabstützend with minimal void volume, after hardening of Binder is used as active Beiastungsaufnehmer in plastic concrete body.

Field of application of the invention

High-strength polyester concrete is because of its excellent mechanical and physical properties, its good theological behavior and special tightness, its resistance to aggressive media and its high abrasion resistance as a building material with appropriately stressed civil engineering z. As the mining industry, the chemical industry or power plant construction can be used advantageously.

Characteristic of the known technical solutions

It is known to produce and use polyester concrete or other synthetic resin concretes. Mostly the application is carried out using one of the polyester concrete adhering property, but also the use z. As shaft excavation material in use of the sum of the properties is known from DD-AP 125344.

A disadvantage is the use of expensive binder resin to see, especially in many publications, the view is taken that with continuous binder addition the good properties, in particular to be achieved with resin concrete strengths increase.

The known limits for compressive strengths of around 100 MPa are at a resin content of 8-16% by weight of the total mixture.

The mechanical-physical properties of the synthetic resin concrete are known to depend on the mixing proportions used from additives, binders, synthetic resin, adhesion promoter, accelerator and hardener.

According to DD-AP 125344, a composition of the polyester concrete with a binder mixture of unsaturated polyester resin with structural and Eiastikharz of 12-16% and 84-88Gew .-% aggregates such as quartz flour 10-40%, basalt granules 2-10mm 25-35 % and grain size 10-22mm 35-55% and the hardener chemicals in wt .-% to the binder content with cyclohexanone peroxide 1.5-3%, cobalt naphthenate (2%) 0.6-1.3%, dimethylaniline solution (10% ig) 0.2-0.4% and para-quinone solution (1%) 0.5-3%, proposed. With achieved strength values such as compressive strengths of 95-100 MPa, tensile strengths between 11 and 11.5 MPa, bending tensile strength of 30 to 31 MPa and absolute watertightness up to 20 MPa, this material is to be used for a resilient expansion for mine shafts.

Publications for polyester concrete, production and properties of SCHIRMER show in polyester concrete a strength behavior that increases approximately linearly with increasing resin content between 5-10% to the total mixture. Thus, with a resin content of 5-10%, the compressive strength is from 21.5 to 133.3 MPa, the tensile strength is from 5.0 to 11.5 MPa, and the flexural tensile strength is from 7.7 to 25.0 MPa, with the fines of the aggregates rose with increasing resin content. About 10% resin content of the total mixture results in only a lower increase in strength. Overall, the achievement of appropriate properties and strengths, however, very much depends on the type of resin used, the reported results are very much determined by the test conditions such as test speed, test temperature, specimen dimensions and their age. In many publications, the lack of this information must be described as a defect, since such results do not allow real classifications of the values determined, especially since uniform test conditions for polyester ketones do not exist.

Object of the invention

It is the object of the invention, while avoiding the existing disadvantages, to make the polyester concrete own advantages over other known building materials for special civil engineering projects also economically cheap.

Explanation of the essence of the invention

The invention has for its object to develop a high-strength, binder-minimized and thus economically cheap to produce polyester concrete and to enable its effective use for appropriate construction projects.

According to the invention, this is achieved by the fact that, contrary to the prior art, a strength increase of the polyester concrete is sought and achieved not in increased resin content, but in the utilization of the strength of the aggregate components and a particularly graded grain skeleton structure using the specific grain shapes of natural and fractured fractions with minimized resin content becomes. In this case, an aggregate mixture is to be used, which leaves with high intrinsic strength in the landfill in vibration and / or compression compacting a small void volume.

The thus created active grain skeleton receives thereby the supporting function, while the binder content, as small as possible, used only for all-round wetting of the aggregate and cavity filling, has to fulfill the binding function and tightness of the building body.

When necessary in practical use cold curing are still in a resin-binder-Antei! of 4.5%, based on the total mixture, achieved a surprisingly high pressure resistance, gas and water tightness, resistance to aggressive media and microbial resistance.

The polyester concrete according to the invention consists of 93 to 95.5 wt .-% of mineral aggregates and from 4.5 to 7 wt .-% of unsaturated polyester resin as a binder.

The aggregate are out of this

Basalt chippings of the grain size 2 to 8mm with 24Gew .-%,

Basalt chippings based on the total aggregate mixture,

Basalt chippings of grain size 4 to 11 mm with 15% by weight

Basalt chippings of grain size 11 to 22mm with 6Gew .-%

Eibsand of grit 0 to 14mm with 35Gew .-% and

Grain grade quartz flour with 20% by weight

composed; the used unsaturated polyester resin AS 2333 still contains cyclohexanone peroxide (50% strength) as hardener with 4% by weight of the binder used and cobalt accelerator (1% strength) with 1% by weight.

To achieve a good bond between binder and additives, 3% by weight, based on the proportions of the additives used, of a 2% strength alcoholic methacrylic silane solution and 3% of distilled water were added to wet the additives.

Furthermore, when using the binder with 4.5 to 5.5 wt .-%, a proportion of 5 wt .-% of styrene contained in the binder.

The starting material polyester resin type AS 2333 of VEB Chemische Werke Buna used for concrete production has the following characteristics:

Viscosity at 293 K 90OcP

at 298 K 65OcP

Density ' 1.15 g / cm ³

Acid number _ 26mg / KOH / g

Styrene content '30%

Styrene uptake 30%

Volume shrinkage 8.3% increase in temperature during cold hardening. 27/426 min / K

Heat cure temperature rise 3.0 / 473 min / K Tensile strength of the cured material 57.5 MPa Ε modulus of the cured material 2.0-10 ³ MPa

The mixed in the compulsory mixer and then compacted under load and vibration polyester concrete according to the invention has the following mechanical-physical and chemical properties within the limits listed, being distinguished even after the slenderness of the test specimens with λ = 1 and λ = 2 in the determined compressive strength.

Compressive strength 'Odbi ·;

Compressive strength Οοβγ;

Splitting tensile strength. o _S z

Fracture squeezing sFe _r;

Initial elastic modulus' E _0;

triaxial compressive strength σ1;

at σ ₂ = O ₃ = 10 MPa

Density [kg / dm ³ ] 2,47

Gas tightness k2-10 ~ ³ mD

Waterproof to 100 MPa waterproof

For special, highly stressed moldings, these are produced from polyester concrete according to the invention with 4.5% to 7% by weight binder content and subjected to a post-curing with a heat treatment at 353 ° K. for five hours, which means a further improvement of the mechanical-physical properties not expected with this low resin content

allows the following values:

λ = 2 100 MPa to 140 MPa λ = 1 110 MPa to 160 MPa 15MPabis17MPa λ = 2 0.7% to 1.05% λ = 2 2,3 -10 ⁴ MPa to 1,1 -10 ⁴ MPa λ = 2 164MPa

Compressive strength λ = 2; O ₀ Br 120 to 150 MPa splitting tensile strength σ SZ 15bis19MPa Compressive failure ε _ΒΓ 0.4 to 0.9% Initial elastic modulus E ₀ 4.05-10 ⁴ MPa to 2.9-10 ⁴ MPa triaxial compressive strength O ₁ 185MPa at σ ₂ = O ₃ = 10 MPa

Density, gas and water tightness are identical to the previously mentioned results.

Long-term tests carried out show the following improvements in their characteristic values compared to the non-post-cured polyester concrete with 7% by weight binder content:

without aftertreatment aftercare 63MPa Qauerstandsstand Od ₀ 52 MPa 0.45% instantaneous compression ε ₀ 0.5% 92MPa Creep strength O _1D 90 MPa triaxial at O ₂ = O ₃ = 10 MPa

All stated strength values were determined under the test conditions mentioned in the exemplary embodiment.

The polyester concrete produced by the above composition is said to be flame-retardant in combustibility, and the flame extinguishes when the fire source is removed. It has a high microbial resistance and a high resistance to aggressive media. Its shrinkage is between 0.23 and 0.25%. The thermal expansion coefficient corresponds to 18 10 ~ ⁶ grd ~ ¹ .

Due to its waterproofness, the polyester concrete has a high freeze-thaw cycling stability.

The high-strength polyester concrete according to the invention, due to its minimized resin-binder content and its good properties in terms of high strength, gas and water tightness, aggression resistance to different, aggressive media and abrasion-stressed civil engineering structures, as well as for the production of polyester concrete Moldings and special expansion elements high strength and tightness, which can be connected by gluing together to form corresponding building structures.

embodiment

The invention will be explained in more detail below with reference to three exemplary embodiments:

Example 1:

The dried at about 473 K and cooled again aggregates are well mixed in appropriate proportions and particle sizes in a rotor mixer. For this purpose, the suitably prepared adhesion promoter is added as alcoholic methacrylic silane solution together with 5 wt .-% of the additive content of distilled water and mixed until uniform wetting of the aggregate grain. The distilled water serves as a wetting aid. After the cooling and cooling, the adhesion promoter-coated aggregate mixture with the binder prepared from corresponding proportions of polyester resin, 50% cyclohexanone peroxide as a hardener, 1% cobalt accelerator as a mixture, which at a binder content of 4.5 to 5.5Gew .-% also Contains 5 wt .-% styrene, well mixed in a rotor mixer and in one for concreting z. B. by shuttering limited space or filled into a shape corresponding to the desired polyester concrete elements. Here is a high compression, for example by vibration, vibration and pressure

 For 1 000 kg of polyester concrete, the following materials are used for a concrete produced with 4.5% by weight of binder:

-4- 253 60ί

a) polyester concrete - net -

b) binders

1. polyester resin

2. Cyclohexanone peroxide (50%)

3. Cobalt accelerator (1%)

4. styrene

c) aggregates

5. Basalt chippings 2-8 mm

6. Basalt chippings 4-11 mm

7. Basalt chippings 11-22 mm

8. Elbe sand .0-4 mm

9. Quartz flour

d) additives

10. Alcoholic methacrylic silane solution (2%)

e) aids

11. distilled water

100% by weight = 1000 kg 4.5% by weight, v. a = 45 kg 90% by weight v. b = 40.5 kg 4% by weight v. b = 1.8 kg 1% w / v. b = 0.45 kg 5% by weight v. b = 2.25kg 95.5wt% v.a = 955.0kg 24.0wt% v. c = 229.2 kg 15.0% w / v. c = 143.25 kg 6.0% by weight v. c = 57.3 kg 35.0% by weight, v. c = 334.25 kg 20.0% by weight v. c = 191.0 kg

3.0% by weight, v. c = 28.65 kg 3.0% by weight, v. c = 28.65 kg

Example 2:

In the same sequence as described in Example 1, the following materials are used for 1 000 kg of polyester concrete with 7 wt .-% binder content, wherein the addition of styrene is omitted in the production of the concrete.

a) polyester concrete - net -

b) binders

1. polyester resin

2. Cyclohexanone peroxide (50%)

3. Cobalt accelerator (1%)

c) aggregates

4. Basalt chippings 2-8 mm

5. Basalt chippings 4-11 mm

6. Basalt chippings 11-22 mm

7. Elbe sand 0-4 mm

8. Quartz flour

d) additives

9. Alcoholic methacrylic silane solution (2%)

e) aids

11. distilled water

100Gew .-% = 1

7Gew .-% v.a

95Gew .-% v. b =

4 wt .-% v. b

1% by weight, v. b

93Gew .-% v. a

24Gew .-% v. c

15wt .-% v. c =

6Gew .-% v. c

35Gew .-% v. c =

20wt .-% v. c

000 kg = 70.0 kg = 66.5 kg = 2.8 kg = 0.7 kg = 930 kg = 223.2 kg = 139.5 kg = 55.8 kg = 325.5 kg = 186.0 kg

3.1% by weight, v. c = 28.83 kg 3.1% by weight v.c = 28.83 kg

Example 3:

The polyester concrete prepared according to Example 1 or 2 is provided according to this example only for appropriate moldings, is then "high density" in dedicated molds and subjected to the normal curing of a post-curing with five hours of heat treatment at 353 K, allowing further improvement of the properties.

The mechanical-physical and chemical properties of the polyester concrete according to the invention or the values named for this purpose were determined by observing the following test conditions:

The specimens were 28 days old and had the dimensions 46 mm 0 and 92 mm in length for the slenderness λ = 2 and 46mm 0 and 46mm in length for λ = 1.

The test temperature was always 293 K at a relative humidity of 60%.

The test specimens are cores drilled out of the polyester concrete cube by 90 ° to the direction of compaction.

The test specimen surfaces were not specially treated.

When the splitting tensile strength was determined, specimens measuring 46 mm in diameter and 25 mm in length were used.

The tests were carried out at a test speed

V = 0.6 ^^ performed

 s

Tests in the triaxial stress state with Karman chamber (σ ₂ = O ₃ * σ-ΐ) were performed mito ₂ = σ ₃ = 10 MPa on test specimens with λ = 2, the results indicating the maximum unbroken endurance stress.

Claims (1)

- 1 - £ .Όύ OUÖ Invention claim: 1. High-strength polyester concrete, which is prepared using mineral additives, unsaturated polyester resin, cyclohexanone peroxide as a hardener and cobalt accelerator, characterized in that it is 93 to 95.5 wt .-%, based on the total mixture of mineral aggregates and 4 , 5 to 7 wt .-% binder of unsaturated polyester resin and at high densification after its curing on specimens with the slenderness λ = 2 has a compressive strength of 100 to 140 MPa, wherein as an aggregate mixture of basalt chippings Vacha grain size , 2-8 mm with 24 wt .-%, Basalt split Vacha of grain size 4-11 mm with 15% by weight, Basalt split Vacha of grain 11-22 mm with 6% by weight, Eibsand Vacha of grain size 0-4 mm with 35% by weight, Quartz flour Vacha of grain size with 20% by weight, based on the total amount of aggregate, and as binder unsaturated polyester resin AS 2333, in which Cyclohexanone peroxide (50%) with 4% by weight