PL243638B1 - Cement-glass composite mix and method of its production - Google Patents

Abstract

The subject of the invention is a mixture and a method for its production, which is a glass composite consisting of glass granulate with a particle size of 0.9/1.5 mm and glass granulate with a particle size of 0/0.9 mm in the proportion 6-9:4-6, sealing additive consisting of glass flour with a thickness of 0/200 μm, or fly ash, or metakaolinite or zeolite in the proportion of 0.15-0.3:10-15 or 0.4-0.7:10-15 or 0, respectively, 6-1:10-15, and cement in the proportions of 5-7:11-14 or 5-7:11-14 or 5-7:11-14, respectively, and a solution of superplasticizer with water with a concentration in the range of 4-10% in the amount of 0.4-0.8% of the weight of the cement used and mixing water in the amount of 20-35% of the weight of the cement used.

Description

Description of the invention

The subject of the invention is a cement-glass composite mixture and a method of its production, which can be used in large-scale and special construction.

The invention belongs to the field of civil engineering of building materials.

Composites containing recycled polymer fibers, combustion by-products - fly ash, waste clays are known from the state of the art.

There are known methods of producing composites by gradually adding aggregate fractions (e.g. quartz sand, basalt, granite) and constantly mixing them with water, cement and other additives (e.g. fluidizers, accelerators, retarders).

The state of the art describes a method for producing a concrete mixture using glass raw materials, described in the application PL391157, intended to create special layers on concrete products, such as the faces of paving stones, the faces of decorative elements, etc. The method involves crushing glass cullet, cleaning, sieving and sorting into fractions. The crystals, preferably multi-colored, are then mixed with the aggregate concrete, preferably adding inorganic paints. The mixture thus prepared is applied to concrete products, creating facing surfaces with special properties.

The solution described in application PL332772 is also known, which consists of cement compositions used to produce concrete and products obtained from these compositions. These compositions contain cement and glass particles, most of which are finely divided. Glass in the form of very fine particles is used as an aggregate for the production of concrete products. Glass is characterized by a large number of particles smaller than 150 microns. The glass is preferably combined with slag, more preferably they are pre-melted together and then ground to particles of the desired size.

Also known is the invention disclosed in application EP0661240, which aims to provide a glass granulate with an alkali-resistant chemical composition in a cement matrix, preferably using recycled glass, in particular bottle and flat glass, and at the same time a method enabling the production of foam glass with specific composition and specific properties. This goal was achieved thanks to the innovative composition of the glass, the oxide content of which for cellular glass granulates is in the following ranges, provided that the sum of all ingredients is 100% by weight: SO2 68.5-75% by weight, Na2O 10-14% by weight, K2O up to 2.5% by weight, Al2O3 1.8-3% by weight, CaO 6-11% by weight, MgO 0.5-4% by weight, Fe2O3 up to 0.5% by weight, SO3 up to 0.4% by weight, TO2 up to 1% by weight, BaO 0.5-3% by weight, others up to 0.5% by weight. The invention relates to cellular glass granules as a lightweight aggregate in, preferably, lightweight cement mortars, lightweight concretes and thermal insulation plasters, and to a method of producing them.

Modern recycling technologies enable the use of waste products in the composition of modern concrete and composite materials. The consequence of using waste materials in composite technology is a reduction in the harmful impact of production on the environment and reduced costs associated with waste disposal.

The compositions of composites based on cement binder are constantly modified and improved by using ingredients (mineral and synthetic additives) from recycled waste materials. Tendencies to deviate from the use of classic mineral aggregates in the composition of modern composite materials are increasingly observed.

One of the proposals to replace conventional aggregates in the composition of concrete and other composites is the use of glass, polymer, metal and organic granulates obtained in the recycling process.

Glass granules in composites act not only as the main component constituting 70-75% of the volume composition (aggregate constituting the crumb pile), but also as a filler, positively influencing the physical properties of the composite - thermal and insulating properties, reduced element weight. Additionally, glass granulate requires less water due to the lack of water absorption compared to pebble or crushed mineral aggregate. The addition of glass in the form of flours with specific fractions has a positive effect on the rheological properties of the composite - ensuring better workability, protection against segregation of mixture components, and obtaining self-compacting properties of the composite.

PL 243638 Β1

The purpose of the invention is a method of producing a building material in the form of an ecological composite with a strength of not less than 80 MPa when compressing a material sample with dimensions of 100-100-100 mm.

At the stage of designing the quantities of individual ingredients of the cement-glass composite mixture recipe, general principles and rules for designing high-quality composites (concrete types: BWW, BBWW and BUWW) were used.

Calculations of the amount of mixing water and cement binder were based on the general formula, the so-called Larrard's formula for the compressive strength of the composite after 28 days. The formula assumed the use of a type II additive specified in concrete standards (an additive with explicit pozzolanic properties or with hidden binding properties using setting reaction activators) in the recipe.

For the needs of the original recipe, Larrard's formula was modified by eliminating the addition of silica fume from the composition of the composite and replacing it with glass flour that does not have binding properties and only seals the crumb stack (as a type I additive - filling additive). The consequence of using glass flour was the reduction of individual quantities included in Larrard's formula (simplification of the formula).

The following assumptions were made at the stage of determining the amount of mixing water and cement:

- the addition of silica dust was eliminated from the composition - the value of the PWC coefficient was reduced to zero;

- the assumed value of the aggregate quality coefficient is kk = 4.9 (dimensionless coefficient in the range of 4.9 + 5.2);

- the assumed strength of the composite after 28 days is 85 MPa (compressive strength of cubic samples).

Larrard's general formula takes the form:

_ ^k ' fcem ^ic ™ “ 1 + 3.1 · w/c

1.4 - 0.4exp (-1.1 where:

kk - coefficient taking into account the influence of aggregate (values in the range of 4.9 + 5.2);

fcem - actual cement strength (standard) [MPa];

w/c - water-cement ratio [dimensionless].

After performing the transformations, the value of the c/w ratio was determined based on the simplified Larrard formula, and then the value of the w/c ratio was determined.

The value of the p/w ratio was (for the assumed data) equal to 3.60149. The value of the w/c ratio was 0.277 (water-cement ratio).

The determined value of the w/c ratio was reduced to 0.26 due to the use of a superplasticizer.

The proportion of these ingredients was selected (experimentally) based on the determined water-cement ratio.

The following water and cement values were determined based on the w/c ratio: water content 125 liters/m ³ and cement 480 kg m ³ (w/c = 0.26).

The amount of filler - glass flour was determined in relation to the determined mass of cement. 5% of cement mass was assumed. The amount of glass flour in the recipe was 24 kg/m ³ .

The chemical admixture used is a third-generation superplasticizer based on an aqueous solution of modified polycarboxylic ether. Experimentally, it was dosed in an amount of 4.5% of the cement mass, which gave 21.6 kg/m ³ .

The amount of aggregate in the recipe was determined based on assumptions and experimental tests of the most advantageous aggregate pile were performed. Having the above-mentioned glass granulate fractions, the granulometric composition was determined using the "dry" sieving method using a laboratory sieve using a basic set of standard sieves. A sieve analysis was performed, based on which the percentage content of individual granulate fractions was determined.

Assumptions for the stage of determining the composition of the crumb pile:

- glass granulate constitutes a maximum of 70% of the volume composition of the entire composite (according to the experimental method, a value of 67% was obtained);

- the ratio of the 0.9-1.5 mm fraction to the 0-0.9 mm fraction group in the range of 1.50 + 1.58 (according to the experimental method, the value of 1.55 was obtained).

Based on the above assumptions, the proportion between the granulate fractions was determined. Finally, the following fraction contents in the composite recipe were determined experimentally: 0-0.9 mm fraction in the amount of 510 kg/m ³ and the 0.9-1.5 mm fraction group in the amount of 790 kg/m ³ (which gives the ratio of these fractions 1.55 granules). The total content of granules was 1,300 kg/m 3.

The composition of the cement-glass composite recipe was developed using existing, general methods for designing high-quality composites. A computational-experimental design method was used. Some assumptions were made that influenced the final general formula for determining the water-cement ratio. Currently, there are no computational methods (without performing experimental tests) that would ensure the possibility of obtaining high-strength composites with repeatable results. The design used general calculations and assumptions that were verified experimentally and finally corrected.

The essence of the invention is a mixture of cement-glass composite containing cement, water and a superplasticizer, which consists of glass granulate with a particle size of 0.9-1.5 mm and glass granulate with a particle size of up to 0.9 mm in a ratio of 6-9:4 -6, where these granulates constitute 2.24-2.7:1 relative to the weight of cement; a sealing additive selected from the group: glass powder with a thickness of up to 200 μm in a proportion of 0.05:1 of the mass of the cement used, fly ash in a proportion of 0.1:1 of the mass of the cement used, metakaolinite in a proportion of 0.15:1 of the mass of the cement used, zeolite in a proportion of 0.2:1 of the weight of the cement used and cement in a dry state and a superplasticizer solution with water with a concentration ranging from 4-10% in an amount of 0.4-0.8% of the weight of the cement used and mixing water in an amount of 20-35 % of the dry weight of cement used.

The essence of the invention is also a method for producing a mixture of cement-glass composite containing cement, water and a superplasticizer, in which glass granulate with a particle size of 0.9-1.5 mm is mixed with glass granulate with a particle size of 0-0.9 mm in a ratio of 6 -9:4-6, so that the mass of the mixture is 2.24-2.7:1 relative to the mass of the cement used, then the obtained mixture of glass granulates is mixed with a sealing additive selected from the group: glass powder with a thickness of up to 200 μm in a proportion of 0 .05:1 of the mass of cement used, fly ash in the proportion of 0.1:1 of the mass of cement used, metakaolinite in the proportion of 0.15:1 of the mass of cement used, zeolite in the proportion of 0.2:1 of the mass of cement used, and then to the obtained mixture a solution of superplasticizer with water with a concentration in the range of 4-10% is added in an amount of 0.4-0.8% of the weight of the cement used, and then the obtained mass is mixed with cement in a dry state, and then mixing water is added in an amount of 20- 35% of the weight of the cement used, stirring constantly, but not less than 3 minutes.

The mixture according to the invention was made according to the following recipes, where the composition of the cement-glass composite recipe was finally determined:

Example 1:

1. Water - 125 liters/m ³ ;

2. Cement - 480 kg/m ³

3. Glass powder up to 200 μm - 24 kg/m ³ ;

4. Superplasticizer - 21.6 kg/m ³ ;

5. Glass granulate 0-0.9 - 510 kg/m ³ ;

6. Glass granulate 0.9-1.5 - 790 kg/m ³ .

Example 2:

1. Cement - 580 kg/m ³ ;

2. Glass granulate 0-0.9 mm - 790 kg/m ³ ;

3. Glass granulate 0.9-1.5 mm - 510 kg/m ³ ;

4. Fly ash - 58 kg/m ³ ;

5. Mixing water - 152 l/m ³ ;

6. Superplasticizer based on an aqueous solution of modified polycarboxylic ether 8.7 kg/m ³ ;

Example 3:

1. Cement - 580 kg/m ³ ;

2. Glass granulate 0-0.9 mm - 790 kg/m ³ ;

3. Glass granulate 0.9-1.5 mm - 510 kg/m ³ ;

4. Metakaolinite - 87 kg/m ³ ;

5. Mixing water - 160 l/m ³ ;

6. Acrylate-based superplasticizer - 8.7 kg/m ³ ;

Example 4:

1. Cement - 580 kg/m ³ ;

2. Glass granulate 0-0.9 mm - 790 kg/m ³ ;

3. Glass granulate 0.9-1.5 mm - 510 kg/m ³ ;

4. Zeolite - 116 kg/m ³ ;

5. Mixing water - 152 l/m ³ ;

6. Acrylate-based superplasticizer - 8.7 kg/m ³ ;

Example 5

In a preferred embodiment, the invention was implemented by mixing 790 kg of glass granulate with a particle size of 0.9-1.5 mm with 510 kg of glass granulate with a particle size of 0-0.9 mm in a laboratory mixer. Mixing took three minutes and was carried out using a zet mixer. Then, the obtained mixture of glass granulates was mixed with 24 kg of sealing additive, which is glass flour with a particle size of up to 200 μm, and mixed for another three minutes. Then, a superplasticizer solution with water with a concentration in the range of 8%, weighing 21.6 kg, was added to the obtained mixture and mixed for three minutes. Then, CEM I cement weighing 480 kg and mixing water with a volume of 125 liters were added to the obtained mixture and the mixture was mixed for another three minutes. After mixing, the cement-glass composite mass was obtained, ready for use.

Example 6

In a preferred embodiment, the invention was implemented by mixing 790 kg of glass granulate with a particle size of 0.9-1.5 mm with 510 kg of glass granulate with a particle size of 0-0.9 mm in a laboratory mixer. Mixing took three minutes and was carried out using a zet mixer. The resulting glass granulate mixture was then mixed with 58 kg of fly ash and mixed for another three minutes. Then, a superplasticizer based on an aqueous solution of modified polycarboxylic ether weighing 8.7 kg was added to the obtained mixture and mixed for three minutes. Then, CEM I cement weighing 580 kg and mixing water with a volume of 152 liters were added to the obtained mixture and the mixture was mixed for another three minutes. After mixing, the cement-glass composite mass was obtained, ready for use.

Example 7

In a preferred embodiment, the invention was implemented by mixing 790 kg of glass granulate with a particle size of 0.9-1.5 mm with 510 kg of glass granulate with a particle size of 0-0.9 mm in a laboratory mixer. Mixing took three minutes and was carried out using a zet mixer. Then the resulting mixture of glass granulates was mixed with 87 kg of the sealing additive, metakaolinite, and mixed for another three minutes. Then, an acrylate-based superplasticizer weighing 8.7 kg was added to the obtained mixture and mixed for three minutes. Then, CEM I cement weighing 580 kg and mixing water with a volume of 160 liters were added to the obtained mixture and the mixture was mixed for another three minutes. After mixing, the cement-glass composite mass was obtained, ready for use.

Example 8

In a preferred embodiment, the invention was implemented by mixing 790 kg of glass granulate with a particle size of 0.9-1.5 mm with 510 kg of glass granulate with a particle size of 0-0.9 mm in a laboratory mixer. Mixing took three minutes and was carried out using a zet mixer. The resulting mixture of glass granulates was then mixed with 116 kg of zeolite and mixed for another three minutes. Then, an acrylate-based superplasticizer weighing 8.7 kg was added to the obtained mixture and mixed for three minutes.

Then, CEM I cement weighing 580 kg and mixing water with a volume of 152 liters were added to the obtained mixture and the mixture was mixed for another three minutes. After mixing, the cement-glass composite mass was obtained, ready for use.

Claims (2)

1. A mixture of cement-glass composite containing cement, water and a superplasticizer, characterized in that it consists of glass granulate with a particle size of 0.9-1.5 mm and glass granulate with a particle size of up to 0.9 mm in a ratio of 6-9 :4-6, where these granulates constitute 2.24-2.7:1 relative to the weight of cement; sealing additive selected from the group: glass powder up to 200 μm thick in a proportion of 0.05:1 of the weight of the cement used, fly ash in a proportion of 0.1:1 of the weight of the cement used, metakaolinite in a proportion of 0.15:1 of the weight of the cement used, zeolite in a proportion of 0.2:1 of the weight of the cement used and dry cement and a superplasticizer solution with water with a concentration ranging from 4-10% in an amount of 0.4-0.8% of the weight of the cement used and mixing water in an amount of 20-35 % of the dry weight of cement used. 2. A method for producing a cement-glass composite mixture containing cement, water and a superplasticizer, characterized in that glass granulate with a particle size of 0.91.5 mm is mixed with glass granulate with a particle size of 0-0.9 mm in a ratio of 6-9 :4-6 so that the mass of the mixture is 2.24-2.7:1 relative to the mass of the cement used, then the obtained mixture of glass granulates is mixed with a sealing additive selected from the group: glass powder up to 200 μm thick in a proportion of 0.05: 1 of the mass of cement used, fly ash in the proportion of 0.1:1 of the mass of cement used, metakaolinite in the proportion of 0.15:1 of the mass of cement used, zeolite in the proportion of 0.2:1 of the mass of cement used, and then the solution is added to the obtained mixture superplasticizer with water with a concentration ranging from 4-10% in an amount of 0.4-0.8% of the weight of the cement used, and then the obtained mass is mixed with cement in a dry state, and then mixing water is added in an amount of 20-35% of the weight cement used, stirring constantly, but not less than 3 minutes.