KR100472345B1 - Concrete composition comprising recycled fine aggregates and recycled coarse aggregates and artificial fishing reef produced by thereof - Google Patents

Abstract

The present invention relates to a concrete composition using recycled aggregate and artificial reef prepared by the concrete composition, more specifically cement 291 ~ 457kg / m ³ , recycled coarse aggregate 764 ~ 994kg / m ³ , natural sand, crushed sand At least one fine aggregate selected from the group consisting of reclaimed sand, 0 to 909 kg / m ³ , a concrete composition comprising water of 35 to 55% of cement weight and a high performance AE reducing agent of 2% or less of cement weight, and the concrete composition It relates to an artificial reef manufactured. Concrete compositions and artificial reefs according to the present invention is excellent in technical development, economic benefits, and socio-environmental effects of using recycled aggregates.

Description

CONCRETE COMPOSITION COMPRISING RECYCLED FINE AGGREGATES AND RECYCLED COARSE AGGREGATES AND ARTIFICIAL FISHING REEF PRODUCED BY THEREOF}

The present invention relates to a concrete composition comprising recycled aggregates and artificial reefs prepared by the concrete composition, more specifically concrete including various fine aggregates such as crushed sand, recycled sand, natural sand and waste concrete recycled coarse aggregates. It relates to a composition and artificial reef prepared by the concrete composition.

In recent years, the company has been promoting sea ranching for offshore fisheries. Artificial reef is a fish house in the sea, and artificially manufactured shapes and materials close to natural grass to maximize the shading effect, feed effect, swirling effect and shelter effect of fish reef, thus improving the productivity of fish and shellfish. It is a structure. In the sea with artificial reefs, phytoplankton and phytoplankton are concentrated, as well as meat shelters and spawning places, forming new fishing grounds, which have more than doubled catches.

According to a survey of fishermen in Jeollanam-do, 92% of the total fishermen say artificial reefs contribute to income improvement. In other words, the catch is stable year-round and catches a lot of high-quality fish. As the artificial reef has proved to be excellent due to continuous experiments and observations, the artificial reef business for protecting fish stocks is gradually increasing. As the artificial reef business is active, technical research on artificial reefs is being conducted. have.

Korean Patent No. 195529 describes an environmental problem caused by manufacturing artificial reefs using new concrete and putting them into the sea and using them, and manufacturing artificial reefs to be discarded in the sea with new concrete is environmentally and costly. In view of this, it is considered to be very unreasonable to solve this problem, and it discloses artificial reef made by pouring and curing the aggregate and cement blended into the reinforcing bar, and the aggregate is a fine aggregate prepared from gravel or waste concrete. And the ratio of the non-aggregate aggregate is characterized in that 1: 6.

In addition, as a technique related to artificial reefs using waste concrete, that is, recycled aggregates, the inventors of the present inventors registration No. 0300704 utility model (concrete artificial reefs using raw aggregate) and `` manufacture technology of artificial reefs using recycled aggregate concrete (Korea Society of Civil Engineers, 2002) Academic papers, etc. are known.

The reason for using recycled aggregates as the main material of artificial reefs is firstly to promote the recycling of construction wastes. According to the comprehensive measures for promoting construction waste recycling (2002) announced by the Ministry of Environment, the annual amount of domestic construction waste is estimated to be about 40,000 thousand tons, of which 24,108 thousand tons are concrete, accounting for 60.9%. The generation of construction waste is expected to increase further, and the rate of construction waste recycling increased to 85.9% in 2001 due to the government's emphasis on recycling policies. However, the use of construction waste accounts for 90% of landfills and landfills, and the performance of recycling in high value-added fields such as road foundations and concrete aggregates is very low, requiring proper countermeasures.

Second, because of the advantages such as excellent permeability and water absorption of the recycled aggregate. Recycled aggregates have a greater permeability than ordinary aggregates, and thus have continuous pores and are capable of producing porous concrete having excellent permeability and permeability. Therefore, it is a material suitable for the production of marine vegetation structures, such as artificial reefs, because it is superior in permeability and absorption than porous concrete using conventional aggregate.

Third, waste concrete recycled aggregates are free from harmful substances. Recycled aggregate refers to recycled crushed stone produced by grinding and processing waste concrete, which is a construction waste, and is classified as a harmless waste and does not require a separate chemical treatment process. In other words, it is environmentally harmless.

However, in order to use such recycled aggregates in artificial artificial reefs, at least 210 kgf / cm ² of compressed aggregate concrete should be developed, and Patent No. 195529 does not provide the required compressive strength. The artificial reefs disclosed in the Utility Model have not only various uses of fine aggregates, but also have disadvantages of economic disadvantage because they have a large unit weight of cement used to provide necessary compressive strength.

Therefore, there are many demands in the art for concrete compositions and artificial reefs manufactured by the concrete compositions, which can use various fine aggregates and provide the required compressive strength while using a small amount of cement.

In order to solve this problem, the present invention is to provide a concrete composition comprising a variety of fine aggregates such as crushed sand, recycled sand, natural sand and waste concrete recycled coarse aggregate and artificial reef manufactured by the concrete composition do.

Another object of the present invention is to provide a concrete composition that can provide the minimum compressive strength required for artificial reefs while reducing the amount of water and cement and artificial reefs made by the concrete composition.

Still another object of the present invention is to provide an artificial reef with a structure that maximizes the vortex effect by the artificial reef while at the same time simplifying the construction.

As an embodiment of the present invention for achieving the above object, the content ratio of water and cement is 35-55%, at least one fine aggregate selected from the group consisting of recycled coarse aggregate and natural sand, crushed sand, recycled sand and high-performance AE water reducing agent It provides a concrete composition comprising a.

The present invention as an embodiment, the cement is 291 ~ 457kg / m ³ , the regenerated coarse aggregate is 764 ~ 994kg / m ³ , the natural sand, crushed sand, at least one fine aggregate selected from the group consisting of regenerated sand 0 ~ 909 kg / m ³ , the high performance AE reducing agent provides a concrete composition that is 2% of the cement weight.

The present invention is an embodiment, the fine aggregate is a combination of any one selected from the crushed sand and natural sand, recycled sand and natural sand, recycled sand and crushed sand, concrete each included in the weight of 330 ~ 460kg / m ³ To provide a composition.

The present invention is an embodiment, the cement is 300-330kg / m ³ , the recycled coarse aggregate is 800-985 kg / m ³ , water is 48-53% of the weight of the cement, the natural sand, crushed sand, reclaimed sand At least one fine aggregate selected from the group consisting of 700 ~ 890 kg / m ³ , the high performance AE reducing agent provides a concrete composition containing 0.5-1.5% of the weight of the cement.

In one embodiment, the fine aggregate is a combination of any one selected from the crushed sand and natural sand, recycled sand and natural sand, recycled sand and crushed sand, each provides a concrete composition comprising 350 ~ 450kg / m ³ do.

As an embodiment of the present invention, any one aggregate aggregate included in the concrete composition provides a concrete composition in which each component is combined at a ratio of 1: 1.

In one embodiment, the recycled coarse aggregate provides a concrete composition of aggregates of between 10 and 25 mm in aggregate size among one, two, and three kinds of aggregates of KS F 2573.

In another aspect, the present invention provides an artificial reef made by the concrete composition, the side of the artificial reef as a circular space, and provides a concrete artificial reef with an X-shaped beam installed inside the reef.

Hereinafter, with reference to the embodiments and the drawings will be described in more detail the technical configuration of the present invention.

The recycled coarse aggregate used in the concrete composition of the present invention is an aggregate of 5 to 25 mm among one, two, and three kinds of aggregates of KS (Korea Standard) F (Civil) 2573 (Compressive Strength Regulation), more preferably. It is to use aggregate between 10 and 25 mm. That is, by removing the coarse aggregate less than 10mm, the absorption rate and wear loss of the aggregate is reduced.

The fine aggregate used in the concrete composition of the present invention should conform to KS regulations, and at least one of natural sand, crushed sand, and recycled sand can be used. Here, natural sand means sand collected naturally from beach, mountain, riverside, etc. Crushed sand means sand made by crushing rock, and recycled sand means sand made by crushing waste concrete.

In the concrete composition of the present invention to improve the chemical resistance by using the blast furnace cement as cement.

On the other hand, high performance AE water reducer is hardened poorly when used in large amount, so in general concrete, it is used within 0.15-0.5% of cement weight. However, in the concrete composition of the present invention, a high performance AE water reducing agent is added in the range of 2% or less of the cement weight, more preferably 0.5-1.5% of the cement weight.

Example 1

Concrete composition using crushed sand, natural sand or crushed sand and natural sand as fine aggregate

Concrete mix ratio shown in Table 1 under the condition that the specific gravity of crushed sand is 2.60, the specific gravity of natural sand is 2.58, the specific gravity of cement is 3.04, the high-performance AE water reducing agent is 1.2% of cement weight, and the air volume is 4.5% of concrete volume. As concrete aggregate of the present invention was prepared using fine aggregate and recycled coarse aggregate.

Example 2

Concrete composition using recycled sand, natural sand or recycled sand and natural sand as fine aggregate

The recycled sand is used instead of the crushed sand and the specific gravity of the recycled sand is 2.58, and the remaining conditions are the same as those of Example 1, and the concrete composition of the present invention was prepared using the fine aggregate and the coarse aggregate of the recycled concrete as shown in Table 2. .

Example 3

Concrete composition using recycled sand, crushed sand or recycled sand and crushed sand as fine aggregate

The recycled sand is used instead of natural sand, and the specific gravity of the recycled sand is 2.58, and the remaining conditions are the same as those of Example 1, and the concrete composition of the present invention was prepared using fine aggregate and recycled coarse aggregate at the concrete mixing ratio shown in Table 3. .

In each table, W / C is water-cement ratio, S / a is fine aggregate ratio, W is unit quantity (water quantity), C is unit cement amount (blast furnace cement), S is unit fine aggregate (S1 = crushed sand, S2). = Sea breeze, S3 = reclaimed sand), G is a unit recycled coarse aggregate.

Experimental Example 1

Experimental results of the ultrasonic speed, slump, and compressive strength of the artificial reef structure manufactured by curing the concrete composition (crushed sand-natural sand as fine aggregate) manufactured by the mixing design of Example 1 (Table 1) are shown. 4 is shown.

Experimental Example 2

The ultrasonic speed, slump, and compressive strength of the artificial reef structure manufactured by curing the concrete composition (regenerated sand-natural sand as fine aggregate) manufactured by the mixing design of Example 2 (Table 2) were tested. 5 is shown.

Experimental Example 3

The ultrasonic speed, slump and compressive strength of the artificial reef structure manufactured by curing the concrete composition (reclaimed sand-crushed sand as fine aggregate) prepared by the mixing design of Example 3 (Table 3) were tested. 6 is shown.

Through the slump results of Tables 4 to 5, it is possible to know workability, and thus the compressive strength.

In addition, Figure 1 shows the relationship between the water-cement ratio (W / C) ratio and the compressive strength according to the use of crushed sand and natural sand as fine aggregate in the concrete composition of Example 1, the higher the water-cement ratio, the higher the compressive strength The lower the unit cement amount. It can be seen that the strength is higher when the mixed sand and the natural sand are used in combination with 100% respectively. It is believed that the compressive strength and the ultrasonic speed are increased because the particle size and workability of fine aggregates due to mixed use are improved.

2 shows the correlation between the residual aggregate ratio (S / a) and the compressive strength as the water-cement ratio increases in the crushed sand-natural sand blending ratio of the concrete composition of Example 1. As the aggregate aggregate increases from 40% to 45% and 50%, the strength tends to increase. In other words, the higher the mixing ratio of the sand can be produced with high strength concrete, it can be seen that the optimum fine aggregate ratio is 50%.

Figure 3 shows the relationship between the water-cement ratio and the compressive strength in the concrete composition according to the use of mixed sand-natural sand, recycled sand-natural sand, recycled sand-crushed sand, based on 50% aggregate aggregate. . When the water-cement ratio is 55%, it is the cheapest in terms of economical efficiency, and it can be seen that the design strength is 210kgf / cm ² or more. When the premium rate is set to 20% to 30%, it can be seen that the compounding strength is in the range of 252kgf / cm ² to 273kgf / cm ² . Even in consideration, the I-WC50Sa50S50 model is suitable.

Although the experimental results for the concrete composition according to the use of recycled sand and natural sand and mixed sand and crushed sand are not shown, the results are similar to those of FIGS. 2 and 3.

On the other hand, the product (D (cm) × V (cm / sec)) of the height (D) and the flow rate (V) of the reef or group of reefs is 1000 or more as the vortex generation condition caused by the artificial reef dropped in the sea desirable. The vortices caused by the waves occur before and after the reefs, and their size is determined by the height, depth and height of the reefs, and is carried downstream by birds. Thus, the occurrence and size of the vortex are determined by various variables.

Therefore, the artificial reef according to the present invention uses a concrete composition composed of the mixing ratios of Examples 1 to 3 to complicate the internal structure in terms of its shape as shown in Figure 4 to make the algae flowing in the sea hit the artificial reef It is designed to maximize the effect of moving the nutrients accumulated in cotton to the upper layer. In this way, if the inside of the square reef is artificially designed to be fine, the microvortices are greatly generated at the front, the bottom, and the rear of the reef, and the formation of the vortex area is larger and wider than the conventional simple square reef. Therefore, because the width and length of the vortices are increased, such as the small vortices inside, the complex vortices behind the reefs, the vortex effect is maximized, the stimulating effect on the fish is increased, and the surface area of the algae is widened. In addition, it is advantageous for preventing settlement of fish and effective stimulation of fish.

However, if the inside of the reef is complicated, it is difficult to manufacture the reef, but when the X-shaped beam is installed inside the artificial reef of the square type as in the present invention, the inside of the reef is complicated, but the construction has a simple advantage. In other words, after assembling the formwork at the top of the reefs can be laid at a time to simplify the construction.

In other words, in order to construct the artificial reefs according to the present invention, first, the reinforcing bars are assembled, and then the formwork is assembled, and the concrete composition prepared according to the present invention is poured at once from the upper surface of the reefs. The structure of the artificial reefs according to the present invention is designed to be easy to construct because the finished reef is cured and then the mold is removed to produce the finished product.

The present invention is not limited to the above-described specific embodiments, and various modifications can be made by those skilled in the art without departing from the gist of the invention as claimed in the claims. Such changes are intended to fall within the scope of the claims.

The present invention proposes the mixing ratio of concrete composition for producing artificial reefs expressing compressive strength of 210kgf / cm ² or more using various fine aggregates and coarse aggregates, and in preparing artificial reefs using the concrete composition of the present invention. There is a remarkable effect that can lead to the optimal formulation design suitable for the aggregate environment in each region of the country.

In addition, the present invention has proposed a variety of formulation design to be used in the production of artificial reefs concrete composition containing recycled aggregates has a remarkable effect of bringing significant technological advances in artificial reefs manufacturing technology.

In addition, according to the present invention, by using waste concrete, which is generated more than 20 million tons per year, in high value-added concrete secondary products, direct economic benefits are generated more than about 40 billion won.

Furthermore, according to the present invention, the recycling of construction wastes, fundamentally solving illegal landfilling and dumping, revitalization of the recycling industry through the consumption of recycled aggregates, and the use of natural aggregates do not use natural aggregates. Environmental expectations are expected.

In addition, the artificial reef of the present invention has an effect of significantly increasing the vortex generation due to the complex structure therein, plankton can be reproduced in large quantities, stimulates various fish species, and widens the surface area of attachment.

1 is a graph showing the water-cement ratio and the compressive strength when using the crushed sand, natural sand, crushed sand-natural sand as the fine aggregate included in the concrete composition of the present invention

FIG. 2 is a graph showing the correlation between fine aggregate fraction and compressive strength with increasing water-cement ratio in FIG.

3 is a relationship between the water-cement ratio and the compressive strength when the residual aggregate contained in the concrete composition of the present invention as 50%, respectively, when using the crushed sand-natural sand, recycled sand-natural sand, recycled sand-crushed sand Graph

Figure 4 is a perspective view of the artificial reef structure manufactured by the concrete composition of the present invention

Claims (8)

Water and cement content ratio of 35-55%, concrete composition comprising one or more fine aggregate and high performance AE reducing agent selected from the group consisting of recycled coarse aggregate, natural sand, crushed sand, recycled sand. According to claim 1, the cement is 291 ~ 457kg / m ³ , the regenerated coarse aggregate is 764 ~ 994kg / m ³ , the one or more fine aggregate selected from the group consisting of the natural sand, crushed sand, regenerated sand 0 ^~ 909 kg / m ³ , The high performance AE reducing agent concrete composition comprising less than 2% of the weight of the cement. The concrete composition of claim 2, wherein the fine aggregate is a combination of any one selected from crushed sand and natural sand, recycled sand and natural sand, recycled sand and crushed sand, and each includes a weight of 330 to 460 kg / m ³ . According to claim 2, wherein the cement is 300-330kg / m ³ , the recycled coarse aggregate is 800-985 kg / m ³ , water is 48-53% of the weight of the cement, the group consisting of the natural sand, crushed sand, recycled sand At least one fine aggregate selected from 700 to 890kg / m ³ , the high-performance AE reducing agent concrete composition containing 0.5-1.5% of the weight of the cement. In claim 4, wherein the fine aggregate is crushed sand and natural sand, it reproduced sand and natural sand, reproduced sand and crushed as any of the combination is selected from sand, respectively 350~450kg / m ³ comprising a concrete composition is. The concrete composition of claim 5, wherein any one of the aggregate aggregates included in the concrete composition is combined in a ratio of 1: 1. The concrete composition according to any one of claims 1 to 6, wherein the recycled coarse aggregate is an aggregate having an aggregate size of 10 to 25 mm among one, two, and three kinds of aggregates of KS F 2573. An artificial reef made of the concrete composition of any one of claims 1 to 7, wherein the side of the artificial reef is a circular space, the concrete artificial reef is provided with an X-shaped beam inside the reef.