KR102661980B1 - Composition for emergently recovering road or ground joint and emergently recovering method road or ground joint - Google Patents

Abstract

A composition for emergency repair of a road or ground cavity, comprising a binder that is a mixture of reduced slag and hemihydrate gypsum, coal bottom ash, and water, wherein the hemihydrate gypsum is contained in 25% by weight of the binder, and the coal bottom ash is the binder and It is contained in 65 to 82% by weight of the total sum of the coal bottom ash, and the binder is contained in 18 to 35% by weight of the total sum of the binder and coal bottom ash, and a composition for emergency restoration of a road or ground cavity, the composition A road or ground cavity emergency repair method comprising the steps of applying is disclosed.

Description

Composition for emergency recovery of road or ground cavity and method of emergency recovery of road or ground cavity {COMPOSITION FOR EMERGENTLY RECOVERING ROAD OR GROUND JOINT AND EMERGENTLY RECOVERING METHOD ROAD OR GROUND JOINT}

The present invention was conceived as a result of research on “Development of commercialization technology for reactive self-leveling filler for emergency recovery based on reclaimed coal material,” and the purpose of the present invention is to provide a fluid fill composition. More specifically, the present invention relates to a composition for emergency repair of a road or ground cavity and a method for emergency repair of a road or ground cavity.

Holes such as sink holes may form in roads or ground due to external forces. If this hole is left as is, it is dangerous because people passing by may fall into it. However, it takes a considerable amount of time to return this hole to its original state. Therefore, it is necessary to temporarily fill this hole with a cavity restoration composition, then dig it out again, and return it to its original state using a composition that can restore it to its original state (commonly referred to as a 'subsequent process').

In general, a composition containing cement or the like has been used as a composition for repairing the cavity. However, existing compositions for cavity restoration have a problem in that the curing speed is not appropriate and the compressive strength is excessively low even in a short period of time.

Therefore, there is a need to develop a composition for cavity restoration that facilitates subsequent processes by ensuring fluidity and bleeding rate while having an appropriate range of compressive strength.

Background technology related to the present invention is disclosed in Republic of Korea Patent Publication No. 10-1720690 (title of the invention: Concrete composition for winter tunnel lining).

It is an object of the present invention to provide a composition for emergency repair of road or ground cavities, which provides the desired fluidity, bleeding rate and compressive strength after curing.

Another object of the present invention is to provide a composition for emergency restoration of roads or ground cavities, which facilitates subsequent processes by having an appropriate range of compressive strength after curing.

One aspect of the present invention is a composition for emergency repair of roads or ground cavities.

The composition for emergency repair of a road or ground cavity includes a binder that is a mixture of reduced slag and hemihydrate gypsum, coal bottom ash, and water, wherein the hemihydrate gypsum is contained in 25% by weight of the binder, and the coal bottom ash is It is contained in 65 to 82% by weight of the total sum of the binder and the coal bottom ash, and the binder is contained in 18 to 35% by weight of the total sum of the binder and the coal bottom ash.

Another aspect of the present invention is a method for emergency repair of a road or ground cavity.

The method for emergency repair of a road or ground cavity includes applying the composition for emergency repair of a road or ground cavity of the present invention to the road or ground cavity.

The present invention provides a composition for emergency repair of road or ground cavities that provides the desired fluidity, bleeding rate, and compressive strength after curing.

The present invention provides a composition for emergency restoration of roads or ground cavities, which facilitates subsequent processes by having an appropriate range of compressive strength after curing.

In describing the present invention, if it is determined that a detailed description of related known technology or configuration may unnecessarily obscure the gist of the present invention, the detailed description will be omitted.

In addition, the terms described below are terms defined in consideration of the functions in the present invention, and may vary depending on the intention or custom of the user or operator, so the definitions should be made based on the content throughout the specification explaining the present invention.

The present invention relates to a composition for emergency repair of roads or ground cavities. The present invention provides a composition for emergency repair of road or ground cavities that simultaneously provides the flowability, bleeding rate, and compressive strength after curing described below.

The fluidity is 210 mm or more when measured according to ACI 229-99, the bleeding rate is 3% or less when measured according to ACI 229-99, and the compressive strength after 4 hours of curing is 0.4 MPa to 2 MPa when measured in UTM. It can be.

If the fluidity is less than 210mm, when the composition is applied to the cavity, it may not flow down properly and the cavity may not be properly filled. If the bleeding rate exceeds 3%, the binder, coal bottom ash, and water in the composition are separated from each other to form a layer, making it difficult to apply to the cavity. If the compressive strength after curing for 4 hours is less than 0.4 MPa, when the composition is applied to the cavity, the strength is weak and it may be difficult to achieve the purpose of emergency recovery of the cavity. If the compressive strength is greater than 2 MPa after curing for 4 hours, subsequent processing may be difficult because the compressive strength is too high after the composition is applied to the cavity.

In one embodiment, the fluidity may be 210 to 300 mm, 240 to 300 mm, the bleeding rate may be 0 to 0.5%, and the compressive strength after curing for 4 hours may be 0.4 to 1.9 MPa.

For detailed measurement methods of fluidity, bleeding rate, and compressive strength after curing, refer to the experimental examples below.

The present invention is a controlled low strength material (CLSM) composition, and is directed to a composition for emergency use on roads or ground cavities.

In order to provide the above-mentioned fluidity, bleeding rate, and compressive strength after curing, the present invention includes only a binder that is a mixture of reduced slag and hemihydrate gypsum as a solid component, and coal bottom ash, and only water as a solvent, and the solid component and Contains no other ingredients other than solvent. The present invention is characterized by providing the above-described fluidity, bleeding rate, and compressive strength after hardening despite being composed of the above-described reduced slag, hemihydrate gypsum, coal bottom ash, and water.

In one embodiment, the composition may have a total amount of reduced slag, hemihydrate gypsum, coal bottom ash, and water of 99 to 100% by weight, preferably 100% by weight of the composition.

In the present invention, the binder is a mixture of reduced slag (CAC) and hemihydrate gypsum, the hemihydrate gypsum is included in 25% by weight of the binder, and the coal bottom ash is 65 to 82% of the total of the binder and the coal bottom ash. It is included in weight%, and the binder is included in 18 to 35% by weight of the total sum of the binder and the coal bottom ash.

Reduction slag is a waste slag with a high basicity that is generated during the process of reducing iron back to iron after oxidation in the electric furnace process of producing iron from scrap iron. Generally, steel slag is divided into blast furnace slag, converter slag, and electric furnace slag, and the electric furnace slag is divided into oxidation slag and reduction slag. In the present invention, the fluidity, bleeding rate, and compressive strength after curing of the present invention were provided by using reduced slag in the composition for emergency restoration of cavities consisting of the above-described hemihydrate gypsum, coal bottom ash, and water.

Reduced slag can be used as slag generated in the electric furnace process, but preferably, powder produced by grinding can be used.

In the present invention, hemihydrate gypsum was used as a binder used with reduced slag. Hemihydrate gypsum is calcium sulfate hemihydrate, a compound expressed as CaSO ₄ .1/2H ₂ O. Generally, gypsum is known as hemihydrate gypsum (CaSO ₄ .1/2H ₂ O), anhydrous gypsum (CaSO ₄ ), and dihydrate gypsum (CaSO ₄ .2H ₂ O). In the present invention, by using hemihydrate gypsum as a binder combined with reduced slag, it is easy to provide the fluidity, bleeding rate, and compressive strength after curing of the present invention.

In the present invention, hemihydrate gypsum is contained in 25% by weight of the binder. In the present invention, it is easy to reach the compressive strength after curing of the present invention by ensuring that the hemihydrate gypsum in the binder, which is a mixture of reduced slag and hemihydrate gypsum, is 25% by weight,

The compressive strength of the present invention becomes too high after curing, making it difficult to remove after curing within the cavity, lowering the re-excavability of the composition into the cavity, and reducing economic feasibility due to the high unit price of hemihydrate gypsum.

The binder is included in 18 to 35% by weight of the total of the binder and coal bottom ash. If the binder is less than 18% by weight, it may be difficult to achieve the fluidity, bleeding rate, and compressive strength after curing of the present invention. If the binder of the present invention exceeds 35% by weight, it may be difficult to achieve the fluidity, bleeding rate, and compressive strength after curing of the present invention.

In the present invention, the binder, which is a mixture of reduced slag and hemihydrate gypsum, additionally includes coal bottom ash, and the coal bottom ash is contained in an amount of 65 to 82% by weight of the total of the binder and coal bottom ash.

In the present invention, the fluidity, bleeding rate, and compressive strength after curing of the present invention were realized by using coal bottom ash in the above content range among coal ash. If the coal bottom ash is included in less than 65% by weight, it may be difficult to achieve the fluidity, bleeding rate, and compressive strength after curing of the present invention. If the coal bottom ash is included in more than 82% by weight, it may be difficult to achieve the fluidity, bleeding rate, and compressive strength after curing of the present invention.

Coal bottom ash is named “bottom ash”. Coal ash is a by-product that remains after burning coal in a coal-fired power plant and is classified into fly ash and bottom ash. Fly ash is ash that is small in size and collected in the air, while bottom ash is ash that is relatively large in size and falls to the bottom of the boiler.

The composition further contains water in addition to reduced slag, hemihydrate gypsum, and coal bottom ash. Water may be contained in the composition in the remaining amount excluding reduced slag, hemihydrate gypsum, and coal bottom ash.

In one embodiment, the ratio of the water content to the binder content in the composition may be 190 to 210% by weight, preferably 200% by weight. Within the above range, it can be easy to implement the effects of the present invention.

In one embodiment, the weight ratio of water to the total of the binder and coal bottom ash in the composition may be 37 to 70% by weight. Within the above range, the fluidity and bleeding rate of the present invention can be easily achieved when the composition of the present invention is applied to the cavity.

The composition of the present invention includes 200 to 300 parts by weight of the binder per unit volume of 1 m ³ of the road or ground cavity to which the composition of the present invention is applied. If the binder is less than 200 parts by weight, the curing rate decreases when the composition is placed in the cavity and cured, making it impossible to achieve the emergency recovery effect of the cavity. If the binder exceeds 300 parts by weight, the curing rate becomes too high when the composition is put into the cavity and cured, so it may be difficult to dig out the cured product after putting it into the cavity and curing it again for post-processing. .

The method for emergency repair of a road or ground cavity of the present invention includes the step of applying the composition for emergency repair of a road or ground cavity to a road or ground cavity.

In one embodiment, the method includes applying the composition for emergency road or ground cavity repair of the present invention to a road or ground cavity and curing the composition. Curing the composition can be performed by conventional methods known to those skilled in the art.

Hereinafter, the configuration and operation of the present invention will be described in more detail through preferred embodiments of the present invention. However, this is presented as a preferred example of the present invention and should not be construed as limiting the present invention in any way. Any information not described here can be technically inferred by anyone skilled in the art, so description thereof will be omitted.

Example 1

A recovery composition was prepared by preparing reduced slag, hemihydrate gypsum, coal bottom ash, and water and mixing them in the amounts shown in Table 1 below.

Examples 2 to 5

A restoration composition was prepared in the same manner as Example 1, except that the content of each component was changed as shown in Table 1 below.

Comparative Examples 1 to 6

A restoration composition was prepared in the same manner as Example 1, except that the content of each component was changed as shown in Table 1 below.

The compositions prepared in Examples and Comparative Examples were evaluated for fluidity, bleeding rate, and compressive strength after curing for 4 hours, 1 day, and 28 days respectively in Table 1 below, and the results are shown in Table 1 below.

(1) Flow (unit: mm): Conducted in accordance with ASTM D 6103「Standard Test Method for Flow Consistency of Controlled Low Strength Material」.

(2) Bleeding rate (unit: %): Evaluated by KS F 2433「Testing method for bleeding rate and expansion rate of injection mortar」.

(3) Compressive strength after curing for 4 hours, 1 day, and 28 days respectively (unit: MPa): In accordance with KS F 2405「Concrete Compressive Strength Test Method」, the test specimen is a mold in the form of a cylinder with a height-to-diameter ratio of 2:1. Use to produce and evaluate a specimen with a height of 100 mm and a diameter of 50 mm.

Reduction slag (kg) Semi-hydrated gypsum (kg) Coal bottom ash (kg) Binder (kg) Reduced slag + hemihydrate gypsum + coal bottom ash (kg) water (kg) Coal bottom ash ratio (% by weight) Binder ratio
(weight%) Hemihydrate gypsum ratio
(weight%) W/B (weight%) W/S (weight%) Comparative Example 1 0.375 0.125 7.52 0.50 8.02 1.00 93.8 6.2 25.0 200.0 12.5 Comparative example 2 0.45 0.15 7.04 0.60 7.64 1.21 92.1 7.9 25.0 200.8 15.8 Comparative example 3 0.525 0.175 6.58 0.70 7.28 1.40 90.4 9.6 25.0 200.0 19.2 Comparative Example 4 0.60 0.20 6.12 0.80 6.92 1.60 88.4 11.6 25.0 200.0 23.1 Comparative Example 5 0.675 0.225 5.64 0.90 6.54 1.81 86.2 13.8 25.0 200.6 27.6 Comparative Example 6 0.75 0.25 5.17 1.00 6.17 2.01 83.8 16.2 25.0 200.5 32.5 Example 1 0.825 0.275 4.72 1.10 5.82 2.20 81.1 18.9 25.0 200.0 37.8 Example 2 0.90 0.30 4.25 1.20 5.45 2.40 78.0 22.0 25.0 200.0 44.0 Example 3 0.975 0.325 3.78 1.30 5.08 2.60 74.4 25.6 25.0 200.0 51.2 Example 4 1.05 0.35 3.32 1.40 4.72 2.80 70.3 29.7 25.0 200.0 59.4 Example 5 1.125 0.375 2.85 1.50 4.35 3.00 65.5 34.5 25.0 200.0 69.0

*Coal bottom ash ratio: Weight ratio of coal bottom ash among (total binder + coal bottom ash)

*Binder ratio: Weight ratio of binder among (total binder + coal bottom ash)

*Hemihydrate gypsum ratio: The weight ratio of hemihydrate gypsum in the binder

*W/B: weight ratio of water to binder

*W/S: Weight ratio of water to (total of binder + coal bottom ash)

division Flow
(mm) Bleeding
(%) Compressive strength as a function of cure time
(MPa) 4hrs 1day 28day Comparative Example 1 205 6.25 0 0 0.21 Comparative example 2 240 4.30 0.03 0.1 0.31 Comparative example 3 250 0.31 0.07 0.15 0.37 Comparative example 4 240 0.65 0 0.31 0.52 Comparative Example 5 270 0.74 0.14 0.32 1.03 Comparative Example 6 260 0.00 0.2 0.49 1.21 Example 1 290 0.00 0.43 1.11 1.82 Example 2 255 0.31 0.95 1.49 2.10 Example 3 255 0.42 1.06 1.91 2.40 Example 4 255 0.30 1.43 2.14 3.00 Example 5 245 0.19 1.84 2.96 3.27

As shown in Table 1 above, the composition of the present invention provided the desired fluidity, bleeding rate, and compressive strength after curing. In addition, the composition of the present invention has a compressive strength within an appropriate range after curing, thereby providing a composition for emergency restoration of roads or ground cavities to facilitate subsequent processes.

On the other hand, the composition of the comparative example that deviates from the composition of the present invention did not achieve all the effects of the present invention.

So far, the present invention has been examined focusing on the embodiments. A person skilled in the art to which the present invention pertains will understand that the present invention can be implemented in a modified form without departing from the essential characteristics of the present invention. Therefore, the disclosed embodiments should be considered from an illustrative rather than a restrictive perspective. The scope of the present invention is indicated in the claims rather than the foregoing description, and all differences within the equivalent scope should be construed as being included in the present invention.

Claims (5)

A composition for emergency restoration of roads or ground cavities,
A binder that is a mixture of reduced slag and hemihydrate gypsum; coal bottom ash; and water,
The hemihydrate gypsum is included in 25% by weight of the binder,
The coal bottom ash is included in 65 to 82% by weight of the total sum of the binder and the coal bottom ash, and the binder is included in 18 to 35% by weight of the total sum of the binder and the coal bottom ash,
The ratio of the water content to the binder content in the composition is 190 to 210% by weight,
A composition for emergency repair of a road or ground cavity, wherein the weight ratio of the water to the total of the binder and the coal bottom ash in the composition is 37 to 70% by weight.
delete delete The composition for emergency repair of a road or ground cavity according to claim 1, wherein the total amount of the reduced slag, the hemihydrate gypsum, the coal bottom ash, and the water is 99 to 100% by weight of the composition.
A method for emergency repair of a road or ground cavity comprising the step of applying the composition for emergency repair of a road or ground cavity of claim 1 or 4.