KR102283993B1 - Modified concrete composition used for building flooring and construction method of flooring using the same - Google Patents

Abstract

The present invention provides: a modified concrete composition used for building flooring, in which a synthetic emulsion is mixed instead of water in a material mixture of concrete to improve adhesion between cement and aggregate, and thus, strength and waterproofness of the installed flooring can be improved, and smooth finish and abrasion resistance can be increased; and a construction method of the flooring using the same. The modified concrete composition used in the building flooring according to the present invention is obtained by mixing 18 to 27 parts by weight of cement, 38-47 parts by weight of fine aggregate, 33-37 parts by weight of coarse aggregate and 2-5 parts by weight of a synthetic emulsion.

Description

Modified concrete composition used for building flooring and construction method of flooring using the same {Modified concrete composition used for building flooring and construction method of flooring using the same}

The present invention relates to modified concrete, and more particularly, modified concrete used for building flooring, which can significantly improve the adhesion between aggregates used in concrete to enhance the strength, abrasion resistance and waterproofness of the constructed flooring material. It relates to a composition and a method of constructing a flooring material using the same.

In general, concrete is made by mixing cement, water, fine aggregate, coarse aggregate, and admixtures as needed. General concrete is inexpensive, durable, and easy to install, making it easy to maintain and maintain, and the shape of the structure to be built can be arbitrarily chosen. There are many advantages such as being able to change it, but the construction speed is slow due to the long curing time and cracks are generated due to drying shrinkage. There is this. When mixing concrete materials, the properties of the composition vary depending on the amount of water and materials mixed. If unnecessarily mixed with a lot of water, workability is improved and the work can be done conveniently and quickly, but the durability of concrete is reduced as well as a lot of problems. As voids are formed, many problems occur, such as cracks in the structure due to drying shrinkage.

Therefore, in the process of making a lot of effort to improve the cracking, durability degradation, and surface wear rate of such concrete structures, Roller Compacted Concrete (RCC) was born. Voltage concrete uses less water and has fewer cracks due to drying and shrinkage, while improving durability, waterproofness, and abrasion resistance. Voltage concrete paving method is a method of voltage compaction after pouring, rather than completing the work by pouring concrete like the general cement concrete paving method. . This voltage concrete pavement has almost no hydration reaction and drying shrinkage that occur during the cement hardening process, and the strength is expressed through the formation of high-density concrete by roller voltage and the interlocking effect between aggregates, and has relatively low unit quantity and unit cement quantity. In spite of this, it has similar strength development characteristics and crack resistance to the existing concrete pavement.

As such, voltage concrete pavement is similar in properties and behavior to general concrete pavement, but it uses much less unit quantity and unit cement quantity and does not require finishing equipment. In addition to strength expression mechanisms such as reaction and voltage effect, voltage concrete using a small amount of unit yields cement with few voids, which induces a decrease in voids in the concrete and improves strength. This voltage concrete pavement is used as a base-layer type of floating road or road with low traffic volume and complex pavement, and is used in some places such as external parking lots.

In relation to voltage concrete, technologies such as Patent Registration No. 1146300 "Construction Method of Road Pavement Structure for Bicycles" and Patent Registration No. 1763346 "Concrete Composition for RCCP" have emerged.

However, not only the above patents but also the voltage concrete that has appeared so far, first, since voltage concrete uses a small amount of water cement, there are fewer cracks due to drying shrinkage, and the compressive strength is increased due to the aggregate bite caused by compaction. , the surface is rough and the aggregate detachment occurs during operation, and the flatness is not constant and road noise and vibration are large during driving, so it is difficult to apply to general parking lot, factory flooring, distribution center flooring, etc.

Second, because cement, aggregate, and a very small amount of water are mixed, there is a limit in improving the adhesion and strength between cement and aggregate, which eventually adversely affects durability, and there is a problem that waterproofness is lowered because a small amount of water is used.

Third, there is a problem in that the frictional force between the concrete floor plate and the voltage concrete increases, but the adhesive force decreases, and the adhesion between the floor plate and the voltage concrete deteriorates, causing a lifting phenomenon during operation.

The present invention has been devised to solve the above problems, and an object of the present invention is to improve the adhesion between cement and aggregate by mixing a synthetic emulsion instead of water when mixing concrete materials, thereby improving the strength and waterproofing properties of the constructed flooring and An object of the present invention is to provide a modified concrete composition for use in building flooring, which can increase smooth finish and abrasion resistance, and reduce cracking factors due to drying shrinkage, and a method of constructing a flooring material using the same.

The modified concrete composition used for the flooring material according to the present invention is composed of 18 to 27 parts by weight of cement, 38 to 47 parts by weight of fine aggregate, 33 to 37 parts by weight of coarse aggregate, and 2 to 5 parts by weight of synthetic emulsion. do.

Another embodiment of the modified concrete composition according to the present invention is mixed with 18 to 27 parts by weight of cement, 37 to 46 parts by weight of fine aggregate, 32 to 36 parts by weight of coarse aggregate, 2 to 5 parts by weight of synthetic emulsion, and 1-3 parts by weight of water. is formed by

Preferably, the synthetic emulsion is, 51 to 54 parts by weight of water, 1-3 parts by weight of sodium dodecyl benzenesulfonate, 46 to 49 parts by weight of copolymer of Styrene butadiene, a A mixture of 1 to 2 parts by weight of chelen and 0.2 to 0.5 parts by weight of a fatty acid vulcanization accelerator is used.

Preferably, the synthetic emulsion is prepared by heating the copolymer stalene butadiene to 90-110° C., then mixing water, acrylicene and a fatty acid vulcanization accelerator at 55-65° C. and mixing for 23-25 hours. After reheating to 90~110℃, mixing and mixing sodium dodecylbenzenesulfonate for 47~50 hours, and then aging while lowering the temperature to 35~40℃ for 95~98 hours.

The method of constructing a flooring material for a building using modified concrete according to the present invention comprises the steps of performing a brooming operation on the base surface in order to increase the adhesion of the modified concrete, mixing and mixing the modified concrete material, and mixing the modified concrete. It is characterized in that the construction is carried out through a step of compaction while installing, a step of flattening the compacted floor surface, and a step of curing.

Preferably, in the step of the brewing operation, the synthetic emulsion and water are mixed in a weight ratio of 1:3 and applied thinly to the base surface.

Since the modified concrete according to the present invention is made by mixing a synthetic emulsion such as SBS synthetic rubber instead of water mixed to cause a hydration reaction with the cement while mixing cement and aggregate with the modified concrete, the synthetic emulsion acts as an adhesive between cement and aggregate. As the adhesive strength of the flooring material is greatly improved, the strength and waterproofness of the installed flooring are remarkably improved, as well as smooth finishing and abrasion resistance can be significantly increased. It is suitable for the construction of interior flooring materials such as In addition, since there are few voids in the concrete, there is no cracking factor due to drying shrinkage, so cracks do not occur.

1 is a flowchart schematically illustrating a construction method of a building flooring material using modified concrete according to the present invention.

The greatest technical feature of the modified concrete according to the present invention is that by using a synthetic emulsion instead of water used while mixing cement and aggregate, the adhesion between cement and aggregate, strength, and waterproofness are improved, and smooth finish as well as abrasion resistance are significantly improved. that it could be increased.

The modified concrete according to the present invention has excellent adhesion, waterproofness, crack resistance, and excellent resistance to chemicals, oil, gasoline, alcohol, solvents, etc. It is suitable for the construction of road and underground parking lot flooring, especially for indoor flooring that requires mechanical stress and flatness.

The mixing ratio of the modified concrete composition according to the present invention is 18 to 27 parts by weight of cement, 38 to 47 parts by weight of fine aggregate, 33 to 37 parts by weight of coarse aggregate, and 2 to 5 parts by weight of synthetic emulsion. First, cement and fine aggregate and After mixing the coarse aggregate, it is preferable to mix the synthetic emulsion and mix it on site.

In addition, depending on the site conditions, if the temperature is 25℃ or higher or if the room where the flooring is installed is dry, a little water may be added. It is composed by mixing 32 to 36 parts by weight of aggregate, 2 to 5 parts by weight of synthetic emulsion, and 1-3 parts by weight of water. First, cement, fine aggregate and coarse aggregate are mixed, and then the synthetic emulsion and water are added and mixed and mixed on site. desirable.

Synthetic emulsion contains 51 to 54 parts by weight of water, 1-3 parts by weight of Sodium Dodecyl benzenesulfonate, 46 to 49 parts by weight of Copolymer of Styrene butadiene, and 1 to 2 parts by weight of Achillene. parts, and 0.2 to 0.5 parts by weight of a fatty acid vulcanization accelerator.

The synthetic emulsion is prepared by first heating the copolymer stalenbutadiene to 90~110℃ to release the particles in the solid state, and then mixing water, acetylene and fatty acid vulcanization accelerator at 55~65℃ for 23~25 hours. After dispersing the copolymer stalenbutadiene particles while reheating to 90 to 110 ° C, mixing sodium dodecyl benzenesulfonate for 47 to 50 hours to ensure fluidity, and then temperature to 35 to 40 ° C for 95 to 98 hours It is preferable to prepare through the steps of aging and stabilizing the synthetic emulsion while lowering it.

Sodium dodecyl benzenesulfonate is a surfactant, and it is a soap component that allows copolymer stalene butadiene, cement, and aggregate to be mixed well with each other. increased, resulting in material separation, and when less than 1 part by weight, it is difficult to mix with each other.

Achillene is an ethylene-based hydrocarbon, and it is used for the purpose of preventing the loss of moisture in the synthetic emulsion. If the amount of acetylene added is more than 2 parts by weight, moisture does not evaporate after construction, so that it does not harden, and when it is less than 1 part by weight, it hardens too quickly.

The fatty acid vulcanization accelerator is an accelerator that gives elasticity in the liquid state by softening the hard crystal form of copolymer stalenbutadiene when compounding the synthetic emulsion. This becomes weak, and when it is less than 0.2 parts by weight, the particles become hard.

Copolymer stalenbutadiene is a synthetic rubber latex produced by emulsion copolymerization. Since water is used as a solvent, it has excellent dispersibility in water and is a synthetic rubber that is stable against cement. If the solid content is more than 49 parts by weight, the compressive strength is lowered and the cement does not harden.

Measurement of change in strength according to the change in the amount of synthetic emulsion in the modified concrete composition Item standard Example 1 Example 2 Example 3 Example 4 Example 5 Synthetic emulsion (parts by weight) - 2-5 0 One 6-10 11-15 Flexural strength (MPa) 4.5 or higher 4.8 1.8 2.6 4.6 4.3 Compressive strength (MPa) 35 or more 39 41 39 34 33 Adhesive strength (㎫) 1.4 or later 1.7 0.0 0.6 1.8 1.8

As shown in [Table 1], when the amount of the synthetic emulsion is large, the adhesion strength is greatly increased, but the compressive strength and the flexural strength are slightly increased, but it can be seen that the strength increase is not large. In addition, when no synthetic emulsion is added or a small amount is added, the compressive strength is increased, but the adhesive strength and the flexural strength are decreased, which is found to be less than the standard value. Therefore, it can be seen that it is not always good to add a lot of synthetic emulsion, and about 2 to 5 parts by weight is the most appropriate.

The construction method of the flooring material for a building using the modified concrete according to the present invention basically cleans the base surface and removes foreign substances and then performs the construction work. In order to increase the adhesion of the modified concrete to the cleaned base surface, A step of brooming (S1), a step of mixing and mixing the modified concrete material (S2), a step of compacting while laying the mixed modified concrete (S3), a step of leveling the compacted floor surface (S4) , it is constructed through a curing step (S5).

In the step (S1) of the brewing operation, since the base surface is cleaned and the base surface is dry, it is preferable to make it wet so that the modified concrete can adhere well to the base surface. Before pouring the modified concrete by mixing :3, sweep it with a brush, etc. and apply it thinly to the base surface.

In the step of installing the reformed concrete, it is desirable to use a dedicated layer to install the thickness of about 3 to 8 cm, and the dedicated layer applies vibration while laying the reformed concrete and compacts it. Since the modified concrete of the present invention uses a synthetic emulsion instead of water, the surface after laying is rough. It is preferable to set the indoor temperature to 5℃ or higher during construction, and 3 to 6 days of curing is sufficient. Existing modified concrete or voltage concrete needs to be compacted separately using compactor rollers and tandem rollers after installation. is a characteristic feature. Since the dedicated layer is not the subject of the present invention, a detailed description of the dedicated layer will be omitted. In addition, since the present invention is constructed through the flattening step (S4), the constructed floor surface is finished very smoothly and the abrasion resistance is also significantly improved.

The results of testing the flexural strength, compressive strength and adhesion strength of the flooring material constructed according to the construction method of the flooring material for a building using the modified concrete of the present invention will be described.

[Flexural strength test]

The specimen for the flexural strength test was manufactured in accordance with KS F 2403 (Method for manufacturing a specimen for strength test of concrete), the cross section of the specimen was 10 cm square, and the length of the specimen was 40 cm. It was tested according to the flexural strength test method of concrete). Flexural strength was calculated according to the following formula.

where R: flexural strength (kg/cm2)

p : Maximum load displayed on the test instrument (kg)

l : length of the trunk (cm)

b: average width (cm)

d: average thickness (cm)

[Compressive strength test]

To measure the compressive strength, according to KS F 2403 (Manufacturing method of specimen for strength test of concrete), three specimens for each age of Φ10×20㎝ were produced and cured in water at 23±15℃ for 7 days. After 7 days, it was cured in an environment of temperature 20±15℃ and humidity 65±20%, and after 28 days of age, a compressive strength test was performed according to KS F 2405 (Testing method for compressive strength of concrete). The compressive strength of the specimen was obtained by dividing the maximum load received by the specimen by the average cross-sectional area of the specimen.

[Adhesive strength test]

For the preparation of the test specimen for adhesion strength test, apply the mixed sample to a 70×70 cm concrete plate according to the mixing ratio with an iron trowel, brush, roller, etc. Specimens cured for 28 days were used for strength test.

Adhesive strength test is in accordance with 5.8 of KS F 4715. Place the specimen after predetermined curing in the curing room horizontally, apply adhesive to the sample application surface, place the upper tension jig (steel) gently, rub gently to adhere, harden for 24 hours, and attach the upper tension jig The maximum tensile load was obtained by applying a tensile force to the specimen at a load rate of 10 mm/min in the vertical direction to the sample surface using an attachment test device. The adhesion strength was calculated by the following formula.

where T : Maximum tensile load N(kgf)

The test results measured by testing according to the test method are shown in [Table 2].

Strength measurement test results Item Standard (KS) the present invention Comparison 1 Comparison 2 Comparison 3 Comparison 4 Flexural strength (MPa) 4.5 or higher 4.8 3.8 3.5 4.1 3.9 Compressive strength (MPa) 35 or more 39 34 39 32 38 Adhesive strength (㎫) 1.4 or higher 1.7 0.2 0.6 0.9 1.0

In [Table 2], Comparative 1 is the existing modified concrete mixed with water, and Comparative 2 to Comparative 4 are specimens prepared using the mixed modified concrete.

When explaining the test results,

① Flexural strength test

Compressive force, shear force, and bending moment force act on the stress acting on a concrete structure. Among them, the most vulnerable is the bending moment force in concrete. In order to supplement the weakness of concrete, reinforced concrete using reinforcing bars and glass fiber reinforced concrete using reinforcing fabric such as glass fiber are used for the purpose of reinforcing various bending forces.

As a result of this test, the flexural strength was 4.8 MPa at the age of 28 days, which is 1.26 times higher than that of the conventional modified concrete using water at 3.8 MPa. This is thought to be due to the strong bonding of aggregates by the integrated co-matrix characteristics between the synthetic emulsion formed inside the concrete and the cement hydrated tissue, and it is expected that the brittleness of the concrete will be improved.

② Compressive strength test

Compressive strength, a physical property of concrete, is representative of other strengths to the extent that the word concrete strength is generally referred to as compressive strength. This is because the compressive strength is considerably larger than other strengths, and it is also effectively used in the design of members, and the size of other strengths and the properties of concrete other than the strength can be roughly estimated from the compressive strength.

As a result of this test, the compressive strength was 39 MPa at the age of 28 days, which was higher than that of general concrete, and the result was higher than the existing modified concrete using water of 34 MPa. It is judged that the strength improvement of the concrete is superior to that of the conventional voltage concrete using water.

③ Adhesive strength test

Adhesion strength is a test item that can evaluate the performance of adhesion to the substrate directly after construction in the field. It can be said that the basic principle is that all materials must be strongly attached to the concrete layer in order to properly express their performance.

As a result of the adhesion strength test, it is 8.5 times higher than that of the existing modified concrete using water, and as a result of applying the sample to a thickness of 5 mm, which is thicker than the normal regulations, even in the drop-off phenomenon, the existing modified concrete using water does not fall between the concrete base and the mortar. However, in the case of the present invention, all of the cases of the present invention showed a phenomenon of biting and falling down to the base concrete. It is judged that the present invention showed excellent improvement in physical properties due to the influence of not only the bonding strength of cement but also the adhesive strength of the film by the synthetic emulsion, compared to relying only on the bonding strength between cement and aggregate.

The above description is illustrative of the present invention, and the embodiments published in the specification are for explanation rather than limiting the technical idea of the present invention, so those of ordinary skill in the art to which the present invention pertains. Various modifications and variations will be possible without departing from the technical idea of Therefore, the protection scope of the present invention should be construed by the matters described in the claims, and technical matters within the scope equivalent thereto should be construed as being included in the scope of the present invention.

Claims (8)

18 to 27 parts by weight of cement;
38 to 47 parts by weight of fine aggregate;
33 to 37 parts by weight of coarse aggregate;
2-5 parts by weight of synthetic emulsion;
It is composed by mixing, and the synthetic emulsion is
51-54 parts by weight of water;
1 to 3 parts by weight of sodium dodecyl benzenesulfonate;
Copolymer of Styrene butadiene 46 to 49 parts by weight;
1 to 2 parts by weight of acrylic;
0.2 to 0.5 parts by weight of a fatty acid vulcanization accelerator;
A modified concrete composition used for building flooring, characterized in that it is a mixture of
18 to 27 parts by weight of cement;
37-46 parts by weight of fine aggregate;
32 to 36 parts by weight of coarse aggregate;
2-5 parts by weight of synthetic emulsion;
1 to 3 parts by weight of water;
It is composed by mixing, and the synthetic emulsion is
51-54 parts by weight of water;
1 to 3 parts by weight of sodium dodecyl benzenesulfonate;
Copolymer of styrene butadiene (Copolymer of Styrene butadiene) 46 to 49 parts by weight;
1 to 2 parts by weight of acrylic;
0.2 to 0.5 parts by weight of a fatty acid vulcanization accelerator;
A modified concrete composition used for building flooring, characterized in that it is a mixture of
delete 3. The method of claim 1 or 2,
The synthetic emulsion is prepared by heating the copolymer stalenbutadiene to 90 to 110° C., then mixing water, acetylene, and a fatty acid vulcanization accelerator at 55 to 65° C. and mixing for 23 to 25 hours.
Reheating to 90~110℃, mixing and mixing sodium dodecylbenzenesulfonate for 47~50 hours, and then aging it while lowering the temperature to 35~40℃ for 95~98 hours. concrete composition.
Brooming to the base surface to increase the adhesion of the reformed concrete;
mixing and mixing the modified concrete material;
compacting while laying the mixed modified concrete;
flattening the compacted floor surface;
curing;
Constructed through
The modified concrete is composed by mixing 18 to 27 parts by weight of cement, 38 to 47 parts by weight of fine aggregate, 33 to 37 parts by weight of coarse aggregate, and 2 to 5 parts by weight of synthetic emulsion,
The synthetic emulsion is, 51 to 54 parts by weight of water, 1 to 3 parts by weight of sodium dodecyl benzenesulfonate, 46 to 49 parts by weight of copolymer of Styrene butadiene, 1 to acetylene 2 parts by weight and 0.2 to 0.5 parts by weight of a fatty acid vulcanization accelerator. Construction method of a building flooring material using modified concrete, characterized in that.
6. The method of claim 5,
In the step of the brewing operation, a method of constructing a flooring material using modified concrete, characterized in that the synthetic emulsion and water are mixed in a weight ratio of 1:3 and applied to the base surface.
delete 6. The method of claim 5,
The modified concrete is characterized in that it is composed by mixing 18 to 27 parts by weight of cement, 37 to 46 parts by weight of fine aggregate, 32 to 36 parts by weight of coarse aggregate, 2 to 5 parts by weight of synthetic emulsion, and 1-3 parts by weight of water. Construction method of building flooring using modified concrete.

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