KR101649262B1 - Method for proportioning recycled aggregate concrete using equivalent mortar - Google Patents

Abstract

A method of recycling aggregate concrete using recycled aggregate without removing the mortar attached to the surface of the aggregate, comprising the step of mixing recycled aggregate concrete with equivalent mortar to reduce the volume of the aggregate aggregate, There is provided a method of recycling aggregate concrete using an equivalent mortar which can easily form recycled aggregate concrete, improve formability, and can be easily applied to low-carbon green airport packaging.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a method for reclaimed concrete using recycled aggregate,

The present invention relates to a method of recycling aggregate concrete, and more particularly, to a method of recycling aggregate concrete using recycled aggregate without removing mortar attached to the surface, Carbon and Green Airport Pavement), and the like. The present invention relates to a method of mixing recycled aggregate concrete using equivalent mortar.

In the face of global pollution and resource depletion problems, the construction of buildings with enormous amount of capital and materials, and the simultaneous use and conservation of resources and energy consumed by the characteristics of the construction industry, The recovery and recycling of resources and energy are required more and more.

For example, the aggregate used in the construction site is a situation where stone aggregates produced in the mountain are commonly used due to depletion of natural aggregate. In order to supply the aggregate of construction, the development of the mountain is progressing, , Which is causing difficulties in the supply and demand of aggregate.

Due to this background, as a construction aggregate for recycled aggregate, which has been recently used as an existing construction waste and used as packing aggregate for embankment cover during illegal landfilling or road pavement, the perception of its utilization is improving.

In the case of construction metropolitan cities, the collection and transportation companies in the jurisdictions receive the waste from the construction site and sort them by their property in the collection house. There is a lot of ways to dispose of the garbage to the landfill site by entrusting it to the intermediate processing company. At this time, after the construction waste is crushed and sorted, the intermediate processing company collects and sells valuable materials such as rebar and recycled aggregate, and the residues are incinerated or landfilled.

However, since the quality and performance of recycled aggregates used in Korea have not yet been shown to be inferior to the quality of natural aggregates and collarbone materials, and it is recognized that it is difficult to apply them to architectural applications, it can be utilized as a high value- There is a desperate need for a plan.

Here, the recycled aggregate refers to aggregates suitable for the provisions of Article 2 (7) of the "Act on the Promotion of Recycling of Construction Waste" (which conforms to the quality standards of Article 35 through physical or chemical treatment processes, etc.) "Recycled aggregate can cause a slight deterioration in the quality of concrete due to the water uptake when the concrete is reproduced. In other words, the recycled aggregate refers to an aggregate that is recycled and reused in the form of aggregate, Aggregate is an aggregate in which the aggregate is recycled and reused in combination with another. Here, although it is usually used indiscriminately, the recycled aggregate is an official name and the recycled aggregate is a name used in the field.

On the other hand, since the amount of waste concrete generated from such construction waste is large, there is no problem in terms of supply, and the composition is also a relatively simple composition of cement mortar and aggregate. Therefore, when the waste concrete is crushed and recycled, And it is estimated that the recycling value is high.

As a recycling method of waste concrete, waste concrete is shredded and used as recycled aggregate for road construction and backfill, method of mixing with natural aggregate in production of concrete secondary product, And a method of cutting and recycling it as a member.

 Recently, it is recommended to mix a certain amount of recycled aggregate with natural aggregate in concrete mix, and it is necessary to select recycled aggregate and natural aggregate in concrete mixture.

Specifically, the recycled aggregate produced by crushing waste concrete has cured cement attached to the aggregate surface. When the recycled aggregate having the cement attached to the surface is exposed to air or reacted with water, the pH rises sharply It becomes strongly alkaline. For example, according to the result of measuring the pH concentration of the recycled aggregate by the waste process test method, it is reported that the recycled aggregate has a pH of about 12 or more.

On the other hand, the amount of unit cement currently applied to concrete pavement at the airport (Airport) is about 60 ~ 100 kg / ㎡ more than the amount of unit cement used in concrete road pavement. Which means more emissions. Accordingly, there is a need to develop a low - carbon, high - strength concrete for airports that can replace cement used in airport concrete pavement with admixture or reduce the amount of unit cement to reduce carbon dioxide emissions and ensure long - term durability.

Especially, airport pavement concrete requires higher strength and higher durability due to higher load than road pavement concrete, so the amount of unit cement is used at a high level. However, there are many types of breakage at present and frequent maintenance is applied . Therefore, it is required to develop a new carbon footprint airport concrete that can achieve high strength and durability required by airport pavement concrete.

On the other hand, in order to reduce the transportation cost and reduce the carbon dioxide emission during the use of the recycled aggregate (or recycled aggregate) in the airport packaging rehabilitation, the natural aggregate Granite), airport site recycled aggregate, and factory recycled aggregate. The properties of coarse aggregate tested are shown in Table 1.

As shown in Table 1, the specific gravity of the natural aggregate is generally 2.6 to 2.7, and the water absorption rate is less than 1%. On the other hand, in the case of recycled aggregate, the specific gravity falls to 2.3 ~ 2.4 due to the mortar attached to the surface, and the absorption rate increases to 3 ~ 5%. At this time, the specific gravity of the mortar is lower than that of the natural stone by about 2.0, so that the specific gravity is lowered, and the absorption rate is increased because of the porous material. In addition, there is an increase in the absorption rate due to the presence of more abrasive grains in the case of making the recycled aggregate than in the conventional natural stone.

In addition, although the recycled aggregate has a low specific gravity and a high water absorption rate as described above, the recycled aggregate has been blended using the same mixing method as the natural aggregate as shown in Table 2 in the conventional concrete formulations.

Specifically, Table 2 shows the concrete formulation table by the general recycled aggregate formulating method, and unit water amount, unit cement amount, coarse aggregate volume, fine aggregate amount, and AE amount are used equally. At this time, in the case of the recycled aggregate, since the water absorption rate is high, if the water content management can not be thoroughly managed, the water is rapidly sucked at the same time as the mixing, and the amount of slump decreases as shown in Table 2.

At this time, when the slump amount is lowered, the workability is reduced at the site construction, and in order to increase the workability in the field, the amount of slump is increased to the same amount of slump as that of the existing natural aggregate. At this time, when the water is increased, there is a side effect of decreasing the strength, and in the case of increasing the water reducing agent, there is a loss in economy.

As another case, there is a case where only the slump amount is blended without controlling the water content of the aggregate in the field. In this case, when the amount of slump is made equal to that of the existing natural aggregate, the water is excessively introduced and the strength is decreased. Also, because of the porosity of the surface of the recycled aggregate, the amount of air tends to be slightly higher than that of the existing natural aggregate.

2 is a view showing the elastic modulus of the natural aggregate, the airport site recycled aggregate, and the plant recycled aggregate, and Fig. 3 is a graph showing the compressive strength of the natural aggregate, the airport field recycled aggregate, Shrinkage ratio of aggregate, airport site recycled aggregate and plant recycled aggregate.

Generally, it is economically more advantageous to use recycled aggregate by controlling the amount of water and adjusting the admixture even if the mixing is difficult compared with the mixing of natural aggregate. However, as shown in FIG. 1, when the natural aggregate and the airport site recycled aggregate are compared, the natural aggregate and the airport site recycled aggregate are compared, Of the total population.

Also, as shown in FIG. 3, when the natural aggregate 1 and the airport field recycled aggregate 1 are compared, the drying shrinkage ratio also increases. This means that even if the strength can be adjusted, the reduction of the material properties other than the strength, such as the elastic modulus and the drying shrinkage, can not be avoided.

4A to 4C are views for explaining the composition of natural aggregate concrete (NAC), conventional recycled aggregate concrete (RAC), and equivalent mortar volume concrete (EMVC).

4A, the natural aggregate 11, the sand 12, the cement 13, the water 14 and the air 15 in the case of the natural aggregate concrete (NAC) The natural aggregate 11 corresponds to a coarse aggregate and the fine aggregate sand 12, cement 13, water 14 and air 15 correspond to mortar.

Referring to FIG. 4B, the recycled aggregate concrete (RAC) 20 includes a raw aggregate 21, an old mortar 22, fine aggregate sand 23, cement 24, water 25 and air 26. The recycled aggregate includes the aggregate 21 and the old mortar 22 as the aggregate-added mortar, and the aggregate 21 corresponds to a coarse aggregate, Old mortar (22), fine aggregate sand (23), cement (24), water (25) and air (26) are mortars.

4C, in the case of equivalent mortar volume concrete (EMVC) 30, the natural aggregate 31, the aggregate 32, the old mortar 33, the sand 34 as a fine aggregate, Wherein the recycled aggregate comprises a wick aggregate (32) and an old mortar (33) which is the mortar-bonded mortar, and the natural aggregate (31) and the water (36) The aggregate 32 corresponds to a coarse aggregate and the old mortar 33, fine aggregate sand 34, cement 35, water 36 and air 37 correspond to the mortar.

Referring to FIGS. 4A to 4C, it is assumed that the amount of the mortar is large as shown in FIG. 4B in the conventional recycled aggregate formulations. For example, comparing FIGS. 4A and 4B, it is assumed that both of them are blended according to a conventional combination, and that the old mortar 22 attached to the recycled aggregate is a mortar having the same properties as the mortar newly formed, The total amount of mortar of the recycled aggregate-form concrete 20 of the concrete aggregate 20 becomes significantly larger than that of the natural aggregate-form concrete 10 shown in FIG. 4A.

As shown in FIG. 4C, when the total mortar volume added with the new mortar volume and the old mortar volume is designed to have the total mortar volume according to the above-described natural aggregate mixing method, the conventional mortar volume Many of the properties can be improved. That is, the equivalent mortar volume concrete (EMVC: 30) refers to designing the total mortar volume plus the new mortar volume and the old mortar volume so as to have the total mortar volume according to the natural aggregate mixed concrete method (10).

FIGS. 5A and 5B are diagrams for explaining the mixing concept of natural aggregate-form concrete and equivalent mortar-volume concrete, respectively.

)이 전체 천연골재 체적(

)이 되고, 신규 모르타르 체적(

)이 전체 모르타르 체적(

)이 된다.Referring to FIG. 5A, in the case of the natural aggregate-form concrete 10, the new natural aggregate volume (

) Is the total natural aggregate volume (

), And the new mortar volume (

) Is the total mortar volume (

).

)이 전술한 천연골재 배합 방법에 따른 전체 모르타르 체적(

)과 동일한 체적으로 설계되며, 전체 모르타르 체적(

)은 다음의 수학식 1과 같이 주어진다.Referring to FIG. 5B, in the case of the equivalent mortar volume concrete 30, the total mortar volume (

) The total mortar volume according to the above-described natural aggregate formulation method (

), And the total volume of mortar (

) Is given by the following equation (1).

은 신규 모르타르 체적을 나타내고,

은 구모르타르 체적을 나타낸다. 또한, 순환골재 체적(

)은 모골재 체적(

)과 구모르타르 체적(

)을 포함한다.here,

Represents a new mortar volume,

Represents the volume of old mortar. Also, the recycled aggregate volume (

) Is the volume of the aggregate (

) And the old mortar volume (

).

)은 전술한 천연골재 배합 방법에 따른 전체 모르타르 체적(

)과 같아지게 되지만, 경화 이전에 유동하는 모르타르량은 감소하게 된다.However, in the case of the above-mentioned equivalent mortar mixing method, the total mortar volume after curing

) Is the total mortar volume according to the above-described natural aggregate mixing method

), But the amount of mortar flowing before curing is reduced.

For example, in the case of conventional structural concrete, a slump of 15 cm is used considering the workability. In this case, when the equivalent mortar volume composition is used, the slump amount is reduced to about 12 cm, but the use is not impaired. However, in the case of conventional concrete mix for pavement, the slump is adjusted to about 4 cm even considering the workability. In this case, when the equivalent mortar volume composition is used, the volume of the coarse aggregate becomes excessively large and the volume of the flowing mortar Is too small to be compounded or causes problems in moldability.

Korean Patent No. 10-1410855 filed on December 2, 2011, entitled "Concrete Mixture Composition and Concrete Mixing Method" Korean Patent Application No. 2009-114162 (Published on November 3, 2009), entitled " Korean Patent No. 10-836598 filed on June 4, 2007, entitled "Concrete Mortar Composition Using Waste Concrete" Korean Patent No. 10-624364 filed on January 12, 2001, entitled "Ready Mixed Concrete Production Method" Korean Patent Publication No. 2011-69743 (Publication date: June 23, 2011), title of the invention: "low carbon emission structural material"

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems and provides a method of recycling aggregate concrete using on-site recycled aggregate without removing mortar adhering to the surface thereof, The present invention is to provide a method for mixing recycled aggregate concrete using equivalent mortar which can reduce the volume of coarse aggregate and increase the volume of flowing mortar to easily form recycled aggregate and improve moldability.

)에 대한 하프 등가모르타르 체적 배합 방법에 따른 신규 천연골재 체적(

)의 비(Ratio)인 R값을 산출하는 단계; d) 하프 등가모르타르 체적 배합 방법에 따른 천연골재의 체적(

) 및 순환골재 체적(

)을 산출하여 전체 굵은골재의 체적(

)을 결정하는 단계; e) 하프 등가모르타르 체적 배합 방법에 따른 신규 모르타르 체적(

)을 산출하는 단계; f) 잔골재(FA), 시멘트(C) 및 물(W) 중량을 산출하는 단계; 및 g) 천연골재의 중량 및 순환골재 중량을 산출하여 하프 등가모르타르 체적 배합 방법에 따른 전체 굵은골재의 중량을 결정하는 단계를 포함하되, 상기 하프 등가모르타르 체적 배합은 순환골재에 부착된 구모르타르 체적을 50%로 축소시키고, 구모르타르 중에서 제1 구모르타르는 굵은골재로 사용하고, 제2 구모르타르는 모르타르로 사용하도록 설계하는 것을 특징으로 한다.As a means for achieving the above technical object, the method of recycling aggregate concrete using the equivalent mortar according to the present invention is characterized by comprising the steps of mixing natural aggregate, (A) calculating an aggregate property for a half equivalent mortar volume; b) determining the natural aggregate formulation according to the natural aggregate formulation method; c) New natural aggregate volume by natural aggregate formulation method (

) Of New Natural Aggregate Volume by Half Equivalent Mortar Volume Mixing Method

(Ratio) between the R value and the R value; d) Volume of natural aggregate according to mixing method of half equivalent mortar volume

) And recycled aggregate volume (

), And the volume of the entire coarse aggregate (

); e) New mortar volume by half-equivalent mortar mixing method

); f) calculating the weight of fine aggregate (FA), cement (C) and water (W); And g) calculating the weight of the natural aggregate and the weight of the recycled aggregate to determine the weight of the entire coarse aggregate according to the half equivalent mortar volume mixing method, wherein the half equivalent mortar volume ratio is calculated by dividing the volume of the old mortar attached to the recycled aggregate Is reduced to 50%, and the first old mortar is used as coarse aggregate and the second old mortar is used as mortar in the old mortar.

)은,

로 주어지고, 여기서,

은 제2 구모르타르 체적을 나타내고,

은 신규 모르타르 체적을 나타내며, 상기 제2 구모르타르 체적(

)은 제1 구모르타르 체적(

)과 동일하며, 구모르타르 체적의 1/2(

)에 해당하는 것을 특징으로 한다.Here, in the half-equivalent mortar volume composition, the total mortar volume (

)silver,

Lt; / RTI >

Represents the volume of the second old mortar,

Indicates a new mortar volume, and the second old mortar volume (

) Is the first former mortar volume (

), Which is 1/2 of the volume of the old mortar (

). ≪ / RTI >

)은, 상기 천연골재 체적(

), 상기 모골재 체적(

) 및 상기 제1 구모르타르 체적(

)을 합산하여 결정되는 것을 특징으로 한다.Here, the volume of the entire coarse aggregate according to the half-equivalent mortar volume mixing method

) Is the natural aggregate volume (

), The parent material volume (

) And the first old mortar volume (

) Are added to each other.

According to the present invention, there is provided a method of recycling aggregate concrete using field recycled aggregate that does not remove the mortar adhered to the surface thereof, wherein the recycled aggregate concrete is mixed using the equivalent mortar to reduce the volume of the aggregate aggregate, The recycled aggregate concrete can be easily compounded and the formability can be improved.

According to the present invention, it is easily applicable to low carbon green airport packaging.

1 is a view showing the compressive strengths of natural aggregates, airport site recycled aggregates and plant recycled aggregates.
2 is a view showing elastic modulus of natural aggregate, airport site recycled aggregate and plant recycled aggregate.
3 is a diagram showing the shrinkage ratio of natural aggregate, airport site recycled aggregate and plant recycled aggregate.
4A to 4C are views for explaining the composition of natural aggregate concrete (NAC), conventional recycled aggregate concrete (RAC), and equivalent mortar volume concrete (EMVC).
FIGS. 5A and 5B are views for explaining the concept of mixing of natural aggregate concrete (NAC) and equivalent mortar volume concrete (EMVC), respectively.
6A and 6B are views showing the composition and concept of a half equivalent mortar volume concrete (HEMVC) according to an embodiment of the present invention, respectively.
7 is a flowchart illustrating a method of mixing recycled aggregate concrete using an equivalent mortar according to an embodiment of the present invention.
8 is a diagram illustrating a basic property combination table of materials required for half-equivalent mortar volume formulation according to an embodiment of the present invention.
FIG. 9 is a graph showing the compressive strength test results according to the half-equivalent mortar volume mixing experiment according to the embodiment of the present invention. FIG.
FIG. 10 is a graph showing the results of bending strength test according to the half-equivalent mortar volume mixing experiment according to the embodiment of the present invention. FIG.
11 is a graph showing the results of the elastic modulus test according to the experiment of mixing the half equivalent mortar volume according to the embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

[Method of recycled aggregate concrete using equivalent mortar]

6A and 6B are views showing the composition and concept of the half-equivalent mortar volume concrete according to the embodiment of the present invention, respectively.

6A, a half-equivalent mortar bulk concrete 100 according to an embodiment of the present invention includes natural aggregate 110, a monolith 120, a first old mortar 131, a second old mortar 132 The recycled aggregate is composed of the aggregate 120, the first old mortar 131 and the second old mortar 140. In this case, The natural aggregate 110, the aggregate 120 and the first old mortar 131 correspond to a coarse aggregate and the second old mortar 132, the sand 140 as a fine aggregate, Cement 150, water 160 and air 170 correspond to the mortar.

)은 다음의 수학식 2와 같이 주어진다.Referring to FIG. 6B, the total mortar volume of the half-equivalent mortar bulk concrete 100 according to the embodiment of the present invention

) Is given by the following equation (2).

은 제2 구모르타르 체적을 나타내고,

은 신규 모르타르 체적을 나타내며, 본 발명의 실시예에 따른 하프 등가모르타르 체적 배합에서 상기 제2 구모르타르 체적(

)은 제1 구모르타르 체적(

)과 동일하며, 구모르타르 체적의 1/2(

)에 해당한다.here,

Represents the volume of the second old mortar,

Represents the new mortar volume, and in the half equivalent mortar volume combination according to the embodiment of the present invention, the volume of the second old mortar (

) Is the first former mortar volume (

), Which is 1/2 of the volume of the old mortar (

).

)은 모골재 체적(

), 제1 구모르타르 체적(

) 및 제2 구모르타르 체적(

)을 포함하고, 전체 굵은골재 체적(

)은 천연골재 체적(

), 모골재 체적(

) 및 제1 구모르타르 체적(

)으로 이루어진다.At this time, the recycled aggregate volume (

) Is the volume of the aggregate (

), The first former mortar volume (

) And second old mortar volume (

), And the total coarse aggregate volume (

) Is the natural aggregate volume (

), The amount of aggregate (

) And the first former mortar volume (

).

In other words, the half-equivalent mortar bulk concrete 100 according to the embodiment of the present invention is a half-mixed model in which the volume of the old mortar is reduced to 50% in the equivalent mortar volume combination shown in FIG. 5B use. In other words, not only concrete properties after curing but also concrete properties before curing are important, so old mortar attached to recycled aggregate is used as mortar and some is designed to behave as coarse aggregate.

Meanwhile, FIG. 7 is a flowchart illustrating a method of mixing recycled aggregate concrete using equivalent mortar according to an embodiment of the present invention.

), 순환골재의 비중(

), 시멘트의 비중(

), 잔골재의 비중, 모골재의 비중(

), 순환골재의 잔류 모르타르 함량(Residual Mortar Content:

)을 각각 산출한다(S110).6A, 6B, and 7, a method of mixing recycled aggregate concrete using equivalent mortar according to an embodiment of the present invention is characterized in that aggregate characteristics for half-equivalent mortar volume mixing, for example, (

), The proportion of recycled aggregate (

), The specific gravity of cement

), Specific gravity of fine aggregate, specific gravity of aggregate (

), Residual mortar content of recycled aggregate (Residual Mortar Content:

( S110 ).

), 물 함량(

), 천연골재의 절대 건조중량(

), 절대 건조 잔골재 함량(

) 및 천연골재 건조중량(

)을 포함한 천연골재 배합을 결정한다(S120).Next, the cement content (%

), Water content (

), Absolute dry weight of natural aggregate (

), Absolute dry fine aggregate content (

) And natural aggregate dry weight (

) Is determined ( S120 ).

값을 산출한다(S130). 여기서,

값은 다음의 수학식 3과 같이 정의되는 순환골재 콘크리트 내의 천연골재의 함량비로서, 다음의 수학식 4와 같이 구해질 수 있다.Next, the ratio of the natural aggregate volume to the natural aggregate volume according to the method of mixing the equivalent mortar volume with the natural aggregate volume according to the natural aggregate mixing method

( S130 ). here,

Is a content ratio of the natural aggregate in the recycled aggregate concrete defined by Equation (3), and can be obtained by the following Equation (4).

는 천연골재 배합 방법에 따른 신규 천연골재 체적을 나타내고,

는 하프 등가모르타르 체적 배합 방법에 따른 신규 천연골재 체적을 나타낸다.here,

Represents a new natural aggregate volume according to the natural aggregate mixing method,

Represents the volume of new natural aggregate according to the method of mixing the half-equivalent mortar volume.

는 순환골재의 잔류 모르타르 함량을 나타내고,

는 순환골재의 비중을 나타내며,

는 모골재의 비중을 나타낸다.here,

Represents the residual mortar content of the recycled aggregate,

Represents the specific gravity of the recycled aggregate,

Represents the specific gravity of the aggregate.

)을 다음의 수학식 5를 이용하여 산출하고, 천연골재 배합 방법에 따른 천연골재의 체적(

)을 다음의 수학식 6을 이용하여 산출함으로써 본 발명의 실시예에 따른 하프 등가모르타르 체적 배합 방법에 따른 전체 굵은골재의 체적(

)을 결정한다(S140). 이때, 상기 전체 굵은골재 체적(

)은 천연골재 체적(

), 모골재 체적(

) 및 제1 구모르타르 체적(

)으로 이루어진다.Next, the volume of the recycled aggregate according to the half-equivalent mortar volume mixing method

) Was calculated using the following equation (5), and the volume of the natural aggregate according to the natural aggregate formulation method

) Was calculated by using the following equation (6) to calculate the volume of the entire coarse aggregate according to the half-equivalent mortar volume mixing method according to the embodiment of the present invention

( S140 ). At this time, the total coarse aggregate volume (

) Is the natural aggregate volume (

), The amount of aggregate (

) And the first former mortar volume (

).

는 천연골재 배합 방법에 따른 천연골재 체적을 나타내고, 다음의 수학식 7과 같이 주어진다.here,

Represents the natural aggregate volume according to the natural aggregate mixing method, and is given by the following Equation (7).

는 천연골재의 절대 건조중량을 나타내고,

는 천연골재의 비중을 각각 나타낸다.here,

Represents the absolute dry weight of the natural aggregate,

Represents the specific gravity of the natural aggregate.

)을 다음의 수학식 8을 이용하여 산출한다(S150). 이때, 하프 등가모르타르 체적 배합의 경우, 일반적으로 순환골재에 부착된 구모르타르 체적이 증가하는 만큼 새로 추가되는 모르타르 체적이 감소하는 경향을 나타낸다.Next, the volume of the new mortar according to the half-equivalent mortar volume mixing method according to the embodiment of the present invention

) Using the following equation (8) ( S150 ). At this time, in the case of the half-equivalent mortar volume composition, as the volume of old mortar attached to the recycled aggregate generally increases, the volume of the newly added mortar tends to decrease.

는 천연골재 배합 방법에 따른 신규 모르타르 체적을 나타내고,

는 하프 등가모르타르 배합 방법에 따른 순환골재의 체적을 나타내며, 이때, 상기 천연골재 배합 방법에 따른 신규 모르타르 체적(

)은 다음의 수학식 9와 같이 주어진다.here,

Shows the new mortar volume according to the natural aggregate mixing method,

Represents the volume of the recycled aggregate according to the half-equivalent mortar mixing method. At this time, the volume of the new mortar according to the method of mixing the natural aggregate

) Is given by the following equation (9).

는 천연골재 배합 방법에 따른 신규 천연골재 체적을 나타낸다.here,

Represents the new natural aggregate volume according to the natural aggregate formulation method.

Next, the new mortar volume is divided by the volume ratio, divided by the respective densities, and the weight of the fine aggregate FA given by the equation (10), the weight of the cement (C) given by the equation (11) ( S160 ).

는 천연골재 배합 방법에 따른 신규 모르타르 체적을 나타내고,

는 하프 등가모르타르 배합 방법에 따른 신규 모르타르의 체적을 나타내며,

는 천연골재 배합 방법에 따른 절대 건조 잔골재 함량을 나타내고,

는 천연골재 배합 방법에 따른 시멘트 함량을 나타내며,

는 천연골재 배합 방법에 따른 물 함량을 각각 나타낸다.here,

Shows the new mortar volume according to the natural aggregate mixing method,

Represents the volume of new mortar according to the half-equivalent mortar combination method,

Shows the absolute dry fine aggregate content according to the natural aggregate formulation method,

Shows the content of cement according to the method of mixing natural aggregate,

Represents the water content according to the method of mixing the natural aggregate.

Next, the volume of the natural aggregate and the volume of the recycled aggregate are divided by the respective densities, and the weight of the natural aggregate given by the following equation (13) and the weight of the recycled aggregate given by the equation (14) ( S170 ).

는 하프 등가모르타르 체적 배합 방법에 따른 신규 천연골재 체적을 나타내고,

는 천연골재의 비중을 각각 나타낸다.here,

Represents the new natural aggregate volume according to the half-equivalent mortar volume mixing method,

Represents the specific gravity of the natural aggregate.

는 하프 등가모르타르 체적 배합 방법에 따른 순환골재의 체적을 나타내고,

는 순환골재의 비중을 각각 나타낸다. 이에 따라 전체 굵은골재의 중량은 천연골재의 중량 및 순환골재의 중량에 따라 결정된다.here,

Represents the volume of the recycled aggregate according to the half-equivalent mortar volume mixing method,

Represents the specific gravity of the recycled aggregate. Accordingly, the weight of the entire coarse aggregate is determined by the weight of the natural aggregate and the weight of the recycled aggregate.

In the case of the recycled aggregate concrete mixing method using the equivalent mortar according to the embodiment of the present invention, the method of recycling aggregate concrete using field recycled aggregate without removing the mortar attached to the surface, The volume of the entire coarse aggregate is reduced and the volume of the flowing mortar is increased. Accordingly, the recycled aggregate concrete can be easily compounded and the formability can be improved.

[Experiment result]

8 is a diagram illustrating a basic property combination table of materials required for half-equivalent mortar volume formulation according to an embodiment of the present invention.

8, for example, the specific gravity of the cement is 3.15, the specific gravity of the fine aggregate is 2.66, and the specific gravity of the natural aggregate is 2.63 , The specific gravity of recycled aggregate is 2.45, and the old mortar amount is given as 32%. The mixing ratio was calculated as 37.3% of water cement ratio, 480 of unit cement content, 46% of fine aggregate content, and 0.39% of AE admixture ratio. At this time, as shown in FIG. 8, the calculated composition is a result of correction through surface water amount and correction through particle size.

In the half-equivalent mortar volume combination method according to the embodiment of the present invention, as shown in Table 3, there are five variables, 1) natural aggregate composition (NA) according to the natural aggregate formulation method, 2) half equivalent mortar volume (EMV50), 3) 100% recycled aggregate volume (EMV100) according to the half-equivalent mortar volume combination method, 4) Circulation according to the existing recycled aggregate mixture method 50% of aggregate volume (RCON50), and 5) 100% recycled aggregate volume (RCON100) according to the existing recycled aggregate formulation method.

Specifically, as shown in Table 3, the natural aggregate mixing method (NV) and the conventional recycled aggregate mixing methods (RCON50 and RCON100) have the same volume ratio when calculated by the volume ratio. However, it can be seen that the half-equivalent mortar volume mixing method (EMV50, EMV100) according to the embodiment of the present invention has a unit water quantity of about 86.1% as compared with the unit quantity of the natural aggregate mixture (NV). In addition, since AE water reducing agent uses a certain magnification of unit cement amount, it can be seen that the use amount of AE water reducing agent is decreased in the case of using a half equivalent mortar volume mixing method (EMV50, EMV100).

Meanwhile, FIG. 9 is a graph showing the results of compressive strength test according to the experiment of mixing the half equivalent mortar volume according to the embodiment of the present invention.

As shown in FIG. 9, the results of the compressive strength test according to the half-equivalent mortar volume mixing experiment according to the embodiment of the present invention show a slight variation depending on the water cement ratio at the time of mixing the half equivalent mortar volume, It can be seen that there is no big difference when compared. Rather, when recycled aggregate is used, it may appear to have a slightly higher compressive strength. For example, in the case of indoor experiment, it is easier to control the hydration state than that of the field mixing because the recycled aggregate is immersed in water for at least one day and then dried at one time in the shade , So that the compressive strength can be increased when the recycled aggregate is used.

10 is a graph showing the results of the bending strength test according to the half-equivalent mortar volume mixing experiment according to the embodiment of the present invention.

As shown in FIG. 10, the results of the bending strength test according to the half-equivalent mortar volume mixing experiment according to the embodiment of the present invention show that there is a certain level change in all the blends based on 7 days old.

11 is a graph showing the results of the elastic modulus test according to the half-equivalent mortar volume mixing experiment according to the embodiment of the present invention.

As shown in FIG. 11, the results of the elastic modulus test according to the experiment of the half-equivalent mortar volume combination according to the embodiment of the present invention are as follows. In the test of the compression strength and the bending strength described above, , It can be seen that the elastic modulus shows a constant tendency. In addition, compared with the natural aggregate method (NA), the 100% recycled aggregate utilization method (RCON100) using the conventional recycled aggregate formulations showed a decrease in the modulus of elasticity of 5.5% Can be seen. On the other hand, in the case of the 100% recycled aggregate utilization ratio (EMV100) according to the half-equivalent mortar volume method according to the embodiment of the present invention, compared with the natural aggregation method (NA), the compressive strength increased by 2.34% Of the total population decreased by only 3.7%.

In the case of the half-equivalent mortar volume combination according to the embodiment of the present invention, when the above-described equivalent mortar volume combination is used, the volume of the coarse aggregate becomes excessively large and the volume of the flowing mortar becomes too small, It is possible to solve the problem of occurrence of a problem in the performance, and a new compounding model such as a 1/3 compounding model other than the 1/2 compounding model can be applied as occasion demands.

As a result, according to the embodiment of the present invention, by using the half-equivalent mortar volume combination to form the recycled aggregate concrete, the volume of the entire coarse aggregate is reduced and the volume of the flowing mortar is increased to easily form the recycled aggregate concrete , And the moldability can be improved. In addition, it can be easily applied to low carbon green airport packaging.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

100: Half equivalent mortar Concrete with volume (HEMVC)
110: Natural aggregate
120:
131: First mortar
132: Second mortar
140: Sand (fine aggregate)
150: Cement
160: water
170: air

Claims (11)

The circulation of the natural aggregate 110, the aggregate 120, the first old mortar 131, the second old mortar 132, the fine aggregate 140, the cement 150, the water 160 and the air 170 In the method of mixing the aggregate concrete (100)
a) calculating an aggregate property for a half equivalent mortar volume;
b) determining the natural aggregate formulation according to the natural aggregate formulation method;
c) New natural aggregate volume by natural aggregate formulation method (

) Of New Natural Aggregate Volume by Half Equivalent Mortar Volume Mixing Method

(Ratio) between the R value and the R value;
d) Volume of natural aggregate according to mixing method of half equivalent mortar volume

) And recycled aggregate volume (

), And the volume of the entire coarse aggregate (

);
e) New mortar volume by half-equivalent mortar mixing method

);
f) calculating the weight of fine aggregate (FA), cement (C) and water (W); And
g) calculating the weight of the natural aggregate and the weight of the recycled aggregate, and determining the weight of the entire coarse aggregate according to the half equivalent mortar volume mixing method
, ≪ / RTI &
In the half-equivalent mortar volume combination, the volume of the old mortar attached to the recycled aggregate is reduced to 50%. In the old mortar, the first old mortar 131 is used as coarse aggregate and the second old mortar 132 is used as mortar In addition,
The aggregate characteristics of the step a)

), The proportion of recycled aggregate (

), The specific gravity of cement

), Specific gravity of fine aggregate, specific gravity of aggregate (

), Residual mortar content of recycled aggregate (Residual Mortar Content:

The method of recycling aggregate concrete using the equivalent mortar according to claim 1, delete The method according to claim 1,
The volume of the entire coarse aggregate according to the half-equivalent mortar volume mixing method

) Is the natural aggregate volume (

), The parent material volume (

) And the first old mortar volume (

) Is added to the total amount of the aggregate concrete. delete The method according to claim 1,
In the step b), the natural aggregate is mixed with the cement content

), Water content (

), Absolute dry weight of natural aggregate (

), Absolute dry fine aggregate content (

) And natural aggregate dry weight (

A method of recycled aggregate concrete using equivalent mortar. The method according to claim 1,
In step c)

The value is the ratio of the content of natural aggregate in the recycled aggregate concrete,

Lt; / RTI >

Represents a new natural aggregate volume according to the natural aggregate mixing method,

Represents the volume of the new natural aggregate according to the half-equivalent mortar volume mixing method,
remind

The value,

Lt; / RTI >

Represents the residual mortar content of the recycled aggregate,

Represents the specific gravity of the recycled aggregate,

Wherein the weight ratio of the aggregate to the total weight of the aggregate is in the range of 0.1 to 10% by weight. [7] The method of claim 6, wherein the volume of the recycled aggregate according to the half equivalent mortar volume mixing method of step d)

)silver,

, Where the volume of the natural aggregate according to the natural aggregate formulation method

)silver

Lt; / RTI >

Represents the volume of the natural aggregate according to the method of mixing the natural aggregate,

Quot;

Lt; / RTI >

Represents the absolute dry weight of the natural aggregate,

Wherein the weight ratio of the natural aggregate to the total weight of the natural aggregate is in the range of 0.1 to 10% by weight. 8. The method of claim 7, wherein the volume of the new mortar according to the half-equivalent mortar volume mixing method in step e)

)silver,

Lt; / RTI >

Shows the new mortar volume according to the natural aggregate mixing method,

Represents the volume of the recycled aggregate according to the half-equivalent mortar mixing method. At this time, the volume of the new mortar according to the method of mixing the natural aggregate

)silver,

Lt; / RTI >

Wherein the natural aggregate volume represents a new natural aggregate volume according to a natural aggregate mixing method. 6. The method of claim 5, wherein the weight of fine aggregate (FA) in step f)

Lt; / RTI >

Shows the new mortar volume according to the natural aggregate mixing method,

Represents the volume of new mortar according to the half-equivalent mortar combination method,

Wherein the amount of the fine aggregate is in the range of 0.1 to 10% by weight based on the total weight of the aggregate. 6. The method of claim 5, wherein the weight of the cement (C) in step (f)

Lt; / RTI >

Shows the new mortar volume according to the natural aggregate mixing method,

Represents the volume of new mortar according to the half-equivalent mortar combination method,

Wherein the cement content of the concrete aggregate is in the range of 0.1 to 10% by weight based on the total weight of the aggregate. The recycled aggregate concrete formulated by the method of recycling aggregate concrete using the equivalent mortar according to any one of claims 1, 3, and 10 to 10.

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