KR102014953B1 - Ground improvement material for deep sea with deep cement mixing by utilizing siliceous slag binder - Google Patents

Abstract

The present invention relates to a solidifying material for a deep seawater mixing method using a silica-based slag fine powder, characterized in that it comprises a stabilizer made of blast furnace slag and cement, and a silica-based slag fine powder. Therefore, the present invention includes a stabilizer and a fine silica-based slag powder as the solidifying material used in the deep seawater mixing method, while realizing the equivalent strength performance while reducing the price compared to the conventional solidified material and at the time of application in the field in addition to the strength performance It improves the locality of the overlap of the city and provides the effect of constructing a composite of equivalent strength or more at the age of 28 days.

Description

GROUND IMPROVEMENT MATERIAL FOR DEEP SEA WITH DEEP CEMENT MIXING BY UTILIZING SILICEOUS SLAG BINDER}

The present invention relates to a solid material for marine deep mixing method using a silica-based slag fine powder, and more particularly to a solid material for a marine deep mixing method using a silica-based slag fine powder used in the marine deep mixing method.

The production of mixed concrete using industrial by-products such as thermal power plants and steel mills has been mass-produced, and as its scope of use expands, its utilization is gradually increasing at home and abroad.

In other words, the development of various cement substitutes is the original technology leading to the development of concrete, such as cost reduction aspect of existing OPC (ordinary Portland Cement) or blast furnace slag cement, or high performance, high durability, high strength, high fluidity, etc. In addition to the development of related cement substitutes, the interest of those in the field is also focused on the development of high performance admixtures and optimum substitution rates to accelerate the securement of the required performance of cement substitutes.

Here, representative examples of those that are conventionally treated as various industrial wastes and recently recognized as admixtures include blast furnace slag powder, fly ash, silica fume, and the like.

In addition, in the case of blast furnace slag powder and fly ash, the demand and supply of domestic products are organically compromised, and in the case of silica fume, the total amount of silica fume is excellent despite the high quality due to the lack of related factories and mass production facilities. Since it depends on the import and the price is high, there was a problem that the purchase cost is considerable.

Republic of Korea Patent No. 10-1035876 (May 20, 2011) Republic of Korea Patent No. 10-1247707 (March 25, 2013) Republic of Korea Patent Publication No. 10-2013-0142470 (December 30, 2013)

The present invention has been made to solve the above-mentioned conventional problems, while lowering the cost compared to the conventional solidified material, while achieving the equivalent strength performance, in addition to the strength performance of the overlapping portion at the time of the initial solidification construction in the field application It is an object of the present invention to provide a solid material for the deep seawater mixing process using silica-based slag fine powder which can be improved and constitute a composite having an equivalent strength or more at the age of 28 days.

In addition, another object of the present invention is to provide a solid material for the deep seawater mixing method using silica-based slag fine powder that can densify the pores of the cement and accelerate the secondary hydration reaction to accelerate the potential hydraulic properties.

In addition, the present invention provides an independent pattern according to the required characteristics of each replacement rate and the purpose of the silica-based slag fine powder, and the cost of the replacement of cement through the improvement of its use and performance improvement while reducing the cost of concrete replacement under various environmental conditions It is another object of the present invention to provide a solid material for deep mixing method using the fine silica-based slag powder that can be applied to construction and manufacturing of various mixed concrete structures requiring high durability.

It is another object of the present invention to provide a solidifying material for a deep seawater mixing method using a fine silica-based slag powder which can improve the reactivity performance while embodying the mechanism of the secondary hydration reaction for the stabilizer and the silica-based slag powder. It is done.

The present invention for achieving the above object, as a solidifying material used in the deep seawater mixing method, a stabilizer made of blast furnace slag and cement; And fine silica-based slag powder.

The said stabilizer of this invention consists of 95-97 weight part with respect to 100 weight part of total, The said silica-type slag fine powder consists of 3-5 weight part with respect to 100 weight part of total.

The fine silica-based slag powder of the present invention is characterized in that the fine powder of handmade ferronickel slag, which is an industrial by-product of ferronickel, is pulverized to a particle size of 3,800 to 26,300 cm 2 / g, and the content of SiO ₂ is 45 to 70%.

The stabilizer of the present invention reacts with water to produce a hydration product, the generated hydration product is reacted with clay minerals in the earth and sand to produce a pozzolanic reaction compound, the silica-based slag powder, It is characterized by forming a modified soil by performing a secondary hydration reaction of the synthesis reaction and additional iron silicate (iron silicate) reaction.

As described above, the present invention includes a stabilizer and a silica-based slag fine powder as the solidifying material used in the deep seawater mixing method, while realizing the equivalent strength performance while reducing the price compared to the conventional solidified material, in addition to the strength performance field application It improves the locality of the overlapped part during the initial solidification construction and provides the effect of constituting a composite of equivalent strength or more at the age of 28 days.

In addition, by limiting the mixing amount of the stabilizer and the silica-based slag fine powder to a predetermined weight part, it is possible to densify the pores of the cement and accelerate the secondary hydration reaction to provide the effect of accelerating the potential hydraulic properties.

In addition, by limiting the particle size of the silica-based slag powder and the content of SiO ₂ to a predetermined amount, it is possible to provide independent patterns according to the required characteristics for each substitution rate and the purpose-specific purposes of the silica-based slag powder, and to improve its use and improve performance. Through the reduction of the cost of replacing cement, it provides an effect that can be applied to the manufacture of mixed concrete structures requiring concrete construction and high durability under various environmental conditions.

In addition, by forming a refined soil by reacting with the stabilizer and the silica-based slag powder, it provides the effect of embodying the mechanism of the secondary hydration reaction for the stabilizer and the silica-based slag powder and at the same time improving the reactivity. do.

1 and 2 are graphs showing the average compressive strength according to the amount of the solidified material for the marine deep mixing method using the silica-based slag fine powder according to an embodiment of the present invention.
Figure 3 is a graph showing the caustic ratio of the solidified material for the marine deep mixing method using a silica-based slag fine powder according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 and 2 are graphs showing the average compressive strength according to the amount of the solidified material for the marine deep mixing method using the silica-based slag fine powder according to an embodiment of the present invention, Figure 3 is a view according to an embodiment of the present invention It is a graph which shows the caustic ratio of the solidification material for the deep sea mixing method using the silica type slag fine powder.

The solidification material for the marine deep mixing method using the silica-based slag fine powder of this embodiment is a solidification material which consists of the stabilizer which consists of blast furnace slag and cement, and a silica-type slag fine powder, and is used for the marine deep mixing method.

The stabilizer is a stabilizer composed of blast furnace slag and cement, and it is composed of 95 to 97 parts by weight based on 100 parts by weight in total, and the stabilizer reacts with water to produce a hydration product, and the hydration product produced therein is clay Reaction with minerals results in the formation of pozzolanic compounds.

The silica-based slag fine powder is a fine powder of handmade ferronickel slag, which is an industrial by-product of ferronickel, at a particle size of 3,800 to 26,300 cm 2 / g, and an additive having a content of SiO ₂ of 45 to 70%, based on 100 parts by weight in total. It is preferable that it consists of 3-5 weight part.

The silica-based slag powder is subjected to the secondary hydration reaction of the pozzolanic reaction compound produced by the stabilizer with a synthetic reaction and an additional iron silicate (Fe ₂ SiO ₄ ) reaction to form an improved soil.

As such, ferronickel slag that emerged as a fourth material as a by-product of the steel industry was originally a ferronickel by-product of steel production, and ferronickel itself is most often used as a main raw material for stainless steel production, and its by-product ferronickel slag Nickel-based stainless steel is excellent in heat resistance, corrosion resistance, acid resistance, abrasion resistance and the like, and has good workability and is used in tableware and kitchen utensils used in general homes as an eco-friendly material harmless to human body.

The main processes of ferronickel production include raw material processing, drying, preliminary reduction, melt reduction (electric furnace), refining and casting, and finally ferronickel containing about 20% nickel and 80% iron. Ferronickel slag refers to handmade by-products that occur in the middle of the furnace process during ferronickel production.

Such ferronickel slag is a useful resource obtained after nickel ore, bituminous coal, etc. used as a raw material for producing ferronickel is melted at high temperature and separated from ferronickel. Ferronickel slag is an environmentally friendly resource with excellent physical and chemical properties, which is used as a substitute for natural resources such as concrete aggregates, foundry sand, abrasives and serpentine substitutes, contributing to the conservation of resources and the environment.

Ferronickel slag is classified into prime stone produced by molten slag rapidly cooling by spraying water with prime stone produced by natural air cooling. In the case of the prime stone, the molten slag is gradually cooled by natural air cooling to produce a gravel form, and the compaction rate is excellent when used as a civil aggregate such as a fill material, subgrade material, asphalt aggregate, and serpentine substitute.

In particular, in the case of prime sand refers to a product produced in the form of sand by spraying water on the molten slag, it has excellent characteristics than natural sand can be used as concrete sand.

In addition, the present invention shows the differentiation and excellence for various indicators through the analysis of comparative literature with the characteristics of the conventional deep sea solidified material, comparative literature analysis in the field where the existing ferronickel slag powder is applied, the contents are as follows: .

First, the raw material quality of silica-based slag fine powder through the milling of ferronickel slag is defined, and secondly, the performance verification for the case of using silica-based slag fine powder as a deep sea solidified material is shown.

Thirdly, when the application of the deep solidified fire at the site called the ground cement, it proved the effect of initial strength delay to resist the occurrence of construction joints and the interference resolution of the overlapping section for sudden environmental conditions such as typhoons and heavy rains, and at the same time, 28 days The result of the superior performance on the effect of on-site agitation performance on the part that satisfies the required design standard strength through the increase in strength at the time of strength is shown.

Fourthly, the theoretical mechanism of the second hydration deformation mechanism of the present invention and data on actual measurement are shown, and fifthly, the result of the test mixture and the results of caustic ratio (price / performance ratio), etc. To present.

Lastly, in terms of price, strength, and durability compared to foreign countries due to the mixed use of fine silica-based slag powder, it is expected to improve the life of the structure and improve competitiveness with overseas countries.

Through this, it is possible to reduce the price competitiveness and increase high value of construction materials by expanding the scope of application to various infrastructures and power plant structures such as roads, bridges, dams, breakwaters, berths, submarine tunnels, and vehicle bases. It will rethink its image as an industry.

First, in relation to the quality of the silica-based slag fine powder through the milling of ferronickel slag, as shown in Table 1, conventional cement (OPC; Ordinary Portland Cement), blast furnace slag fine powder (GGBS; ground granulated blast slag) ), PFA (Pulverised Fly Ash), Silica Fume (SF), and other chemical components.

division CaO SiO ₂ Al ₂ O ₃ MgO OPC 61.4 20.5 6.4 3.0 GGBS 33.5 44.2 14.0 4.9 PFA 4.2 55.0 21.1 1.2 SF 0.6 96.7 0.3 0.2 Silica Slag Powder 2.1 62.8 1.9 24.7

In addition, in the present invention, the basis as a binder through the variables for the specific surface area (powder degree: cm ² / g) of the general cement and three types of ferronickel slag (FNS (Low), FNS (Medium), FNS (High)) Comparative evaluation of the physical properties is shown as shown in Table 2.

% Powder
(cm ² / g) importance
(g / cm ³ ) Ignition loss
(%) Cl ^-
(%) Cr ⁶⁺
(mg / kg) SO ₃ OPC 3,712 3.10 2.43 0.017 7 2.23 FNS (L) 4,666 3.05 0.00 0.024 0 0.53 FNS (M) 8,600 3.02 0.00 0.020 0 0.29 FNS (H) 26,300 3.02 0.01 0.029 0 0.26

In addition, to explain the performance verification for the case of using the silica-based slag fine powder of the present embodiment as a deep sea solid material, the contents of various basic physical property tests will be shown as follows.

Table 3 below shows the results of the basic physical properties of the sandy soil.

Table 4 below shows the compounding conditions.

Hereinafter, Table 5 shows the amount of material for compounding.

Target soil classification Target soil
Water content (%) Target volume
(kg / m ³ ) Binding capacity
(B) (kg / m ³ ) Water (sea water)
(kg / m ³ ) W / B sand 30 2013 210 147 70 30 2013 230 161 70 30 2013 250 175 70 30 2013 280 196 70 30 2013 300 210 70 sand 30 2013 210 168 80 30 2013 230 184 80 30 2013 250 200 80 30 2013 280 224 80 30 2013 300 240 80

Table 6 below shows the yield of each material according to the compounding table. (Test specimen 5cm * 10cm, 9 production conditions)

The following is a test example for the mixing of materials and the preparation and curing of the specimens. The binder and the number of water used were weighed using a weighing capacity of 4 kg and a sensitivity of 0.01, and the weighing of the soil was used with a weighing scale of 30 kg and a sensitivity of 1 g.

In addition, the sand mixed material was filled in a test mold (5 cm in diameter x 10 cm in height), and then chopped with a compaction rod to smooth the surface and sealed with vinyl. Surface finish was capped with cement paste.

Next, the prepared specimens were cured with wet curing (20 ± 3 ° C., humidity of 95% or more) to a predetermined age.

Table 7 shows the compressive average compressive strength (MPa) for each age.

In addition, it has the initial strength delay effect to resist the occurrence of construction joints against sudden environmental loads when the deep solidified material is applied at the site called the ground cement, as well as the required design standard strength by increasing the strength at the 28-day strength point. The results of the verification of the effect of on-site agitation for the part satisfying the results are shown in Table 7.

Two types of cement and blast furnace slag are used as existing stabilizers, and the rapid strength expression at these early ages makes it difficult to overlap construction during actual site construction.

In addition, the purpose of applying the diameter cement as described above is to ensure the cutting and overlapping of the existing ground even after the atmosphere and the sea, the atmosphere and the rest, and to improve the reliability of the overlapping part by adopting the discharge during penetration, and to develop the initial strength. It becomes possible to suppress it.

Therefore, the mixed cement using the silica-based slag fine powder of the present invention can increase the stability of the soil under medium-term age according to the increase in long-term strength, and the sound durability by improving the salt resistance and chemical erosion resistance compared to the general cement It can increase the lifespan.

In addition, as a result of the test of the cemented marine deep solidified material indoors, the initial strength is suppressed on the 7th and 14th days, and the result is exceeded at the 28th day. Continuous construction is possible by improving the reliability of the phosphorus overlapping portion.

As described above, according to the present invention, by including the stabilizer and the silica-based slag fine powder as the solidifying material used in the deep seawater mixing method, the field application in addition to the strength performance while at the same time lowering the price compared to the conventional solidified material It improves the locality of the overlapped part during the initial solidification construction and provides the effect of constituting a composite of equivalent strength or more at 28 days of age.

In addition, by limiting the mixing amount of the stabilizer and the silica-based slag fine powder to a predetermined weight part, it is possible to densify the pores of the cement and accelerate the secondary hydration reaction to provide the effect of accelerating the potential hydraulic properties.

In addition, by limiting the particle size of the silica-based slag powder and the content of SiO ₂ to a predetermined amount, it is possible to provide independent patterns according to the required characteristics for each substitution rate and the purpose-specific purposes of the silica-based slag powder, and to improve its use and improve performance. Through the reduction of the cost of replacing cement, it provides an effect that can be applied to the manufacture of mixed concrete structures requiring concrete construction and high durability under various environmental conditions.

In addition, by forming a refined soil by reacting with the stabilizer and the silica-based slag powder, it provides the effect of embodying the mechanism of the secondary hydration reaction for the stabilizer and the silica-based slag powder and at the same time improving the reactivity. do.

The present invention described above can be embodied in many other forms without departing from the spirit or main features thereof. Therefore, the above embodiments are merely examples in all respects and should not be interpreted limitedly.

Claims (1)

As a solid material used in the deep sea mixing process,
Stabilizer composed of blast furnace slag and cement; And
Including silica-based slag fine powder,
The stabilizer is composed of 95 to 97 parts by weight based on 100 parts by weight of the total,
The fine silica-based slag powder is composed of 3 to 5 parts by weight based on 100 parts by weight of the total,
The cement consists of hard cement,
The fine silica-based slag powder is finely ground the handmade ferronickel slag, which is an industrial by-product of ferronickel, at a particle size of 3,800 to 26,300 cm 2 / g, and the content of SiO ₂ is 60 to 70%.
The stabilizer reacts with water to produce a hydration product,
The produced hydration product is reacted with the clay mineral in the soil sand to produce a pozzolanic reaction compound,
The fine silica-based slag powder is a silica-based slag, characterized in that to form an improved soil by performing a secondary hydration reaction of the produced pozzolan reaction compound and the addition of iron silicate (Fe ₂ SiO ₄ ) reaction Solid fire for deep mixing process using fine powder.

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