KR20130068371A - Management method of ultra high strength concrete for maximizing strength properties - Google Patents

Management method of ultra high strength concrete for maximizing strength properties Download PDF

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KR20130068371A
KR20130068371A KR20110135476A KR20110135476A KR20130068371A KR 20130068371 A KR20130068371 A KR 20130068371A KR 20110135476 A KR20110135476 A KR 20110135476A KR 20110135476 A KR20110135476 A KR 20110135476A KR 20130068371 A KR20130068371 A KR 20130068371A
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strength concrete
ultra
high strength
strength
concrete
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KR101314799B1 (en
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이승훈
이우진
이주하
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삼성물산 주식회사
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Priority to SG2013012828A priority patent/SG190763A1/en
Priority to MYPI2013000581A priority patent/MY160215A/en
Priority to PCT/KR2012/010795 priority patent/WO2013089431A2/en
Priority to IN309MUN2013 priority patent/IN2013MN00309A/en
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    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/02Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B18/00Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
    • C04B18/04Waste materials; Refuse
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B14/00Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
    • C04B14/02Granular materials, e.g. microballoons
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B40/00Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
    • C04B40/0028Aspects relating to the mixing step of the mortar preparation
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B40/00Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
    • C04B40/0028Aspects relating to the mixing step of the mortar preparation
    • C04B40/0032Controlling the process of mixing, e.g. adding ingredients in a quantity depending on a measured or desired value
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B40/00Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
    • C04B40/02Selection of the hardening environment
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/60Flooring materials
    • C04B2111/62Self-levelling compositions
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2201/00Mortars, concrete or artificial stone characterised by specific physical values
    • C04B2201/50Mortars, concrete or artificial stone characterised by specific physical values for the mechanical strength
    • C04B2201/52High compression strength concretes, i.e. with a compression strength higher than about 55 N/mm2, e.g. reactive powder concrete [RPC]
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02WCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00Technologies for solid waste management
    • Y02W30/50Reuse, recycling or recovery technologies
    • Y02W30/91Use of waste materials as fillers for mortars or concrete

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Civil Engineering (AREA)
  • Environmental & Geological Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Inorganic Chemistry (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)
  • On-Site Construction Work That Accompanies The Preparation And Application Of Concrete (AREA)
  • Preparation Of Clay, And Manufacture Of Mixtures Containing Clay Or Cement (AREA)

Abstract

PURPOSE: A manufacturing method of ultrahigh strength concrete is provided to reinforce the stability of a structure by establishing the structure on the basis of the ultrahigh strength concrete. CONSTITUTION: Ultrahigh strength concrete is made of water, cement, silica fume, blast furnace slag, gypsum, fine aggregate, and coarse aggregate and is admixed to have 20 weight% or less of a water-admixture ratio and 120 Mpa or more of compressive intensity. A management method of the ultrahigh strength concrete includes the following steps: the slump flow of ultrahigh strength concrete admixture is designed to be at the level of 850±50mm; the air volume of the ultrahigh strength concrete admixture is designed to be in a range between 1.0 and 2.0%; the coarse aggregate and the silica fume are dry-mixed for 20-50 seconds, and other materials are mixed; water is lastly introduced into the admixture, and the admixture is mixed for 150-200 seconds, maintained for 200-400 seconds, and re-mixed for 150-200 seconds; the ultrahigh strength concrete is self-compacting placed; and the ultrahigh strength concrete is wet-cured for 14-28 days and is air dry-cured.

Description

강도발현의 극대화를 위한 초고강도 콘크리트의 관리방법{Management Method of Ultra High Strength Concrete for Maximizing Strength Properties}Management Method of Ultra High Strength Concrete for Maximizing Strength Properties

본 발명은 초고강도 콘크리트의 강도발현을 극대화하기 위한 방법에 관한 것으로, 더욱 상세하게는 동일한 배합재료에 의한 동일한 배합설계에서 초고강도 콘크리트 경화체의 강도발현을 극대화할 수 있는 방법에 관한 것이다.
The present invention relates to a method for maximizing the strength expression of ultra-high strength concrete, and more particularly, to a method for maximizing the strength expression of hardened concrete of the ultra-high strength concrete in the same mixing design by the same compounding material.

최근 초고층 구조물의 증가에 따라 초고강도 콘크리트에 대한 관심이 증대하고 있다. 초고강도 콘크리트의 적용으로 기둥, 보 등의 부재 단면을 줄일 수 있어 골조경비를 절감할 수 있고, 나아가 부재 단면의 축소에 따라 넓은 내부 공간을 확보할 수 있어 효율적인 공간 활용이 가능해지기 때문이다.Recently, with the increase of the high-rise structure, interest in ultra-high strength concrete is increasing. This is because the application of ultra-high strength concrete can reduce the cross section of columns and beams, which can reduce the cost of framing, and furthermore, it is possible to make efficient use of space by securing a large internal space as the cross section is reduced.

초고강도 콘크리트라고 하면 경화 콘크리트가 120MPa 이상의 압축강도를 발현하는 경우를 의미한다. 초고강도 콘크리트는 시멘트 외에 실리카퓸, 고로슬래그 미분말, 플라이애시, 석고 등을 결합재로 채택하고 낮은 물-결합재비로 배합설계하며, 최근에는 200MPa급 극초고강도 콘크리트의 배합설계 방법까지 제안되고 있다.Ultra-high strength concrete means a case where the hardened concrete expresses a compressive strength of 120 MPa or more. Ultra-high strength concrete adopts silica fume, blast furnace slag powder, fly ash, gypsum as a binder in addition to cement, and mixes it with low water-bonding ratio. Recently, it has been proposed to mix the design of ultra-high strength concrete of 200MPa grade.

한편 초고강도 콘크리트는 낮은 물-결합재비를 갖기 때문에 배합재료 간 혼합이 잘 이루어지지 않으며, 그 결과 실제 경화체는 설계강도대로 강도발현이 이루어지지 않을 수 있다. 소정의 설계강도에 따라 배합하더라도 배합재료 간 혼합이 어려워 설계강도보다 한참 낮게 강도발현이 이루어지는 것이다. 극히 낮은 물-결합재비의 200MPa급 초고강도 콘크리트는 더욱 그러하다.
On the other hand, because the ultra-high strength concrete has a low water-bonding material ratio, mixing between the blending materials is not performed well, and as a result, the actual hardened body may not be formed at the strength of the designed strength. Even when formulated according to the predetermined design strength, it is difficult to mix the blending materials, so that the strength is significantly lower than the design strength. This is especially true for 200MPa class super high strength concrete with extremely low water-binding ratio.

본 발명은 종래 초고강도 콘크리트의 낮은 물-결합재비에 따른 강도발현 문제를 개선하고자 개발된 것으로서, 동일한 배합재료에 의한 동일한 배합설계에서 강도발현을 극대화시킬 수 있는 방법을 제공하고자 한다.
The present invention was developed in order to improve the strength expression problem according to the low water-bonding material ratio of the conventional ultra-high strength concrete, and to provide a method that can maximize the strength expression in the same mixing design by the same compounding material.

상기한 기술적 과제를 해결하기 위해 본 발명은 물, 시멘트, 실라카퓸, 고로슬래그, 석고, 잔골재, 굵은 골재를 포함하는 배합재료를 가지고 20중량% 이하의 낮은 물-결합재비로 120MPa 이상의 압축강도로 배합설계되는 초고강도 콘크리트의 강도발현을 극대화하기 위한 방법으로서, 다음의 방법을 제공한다. In order to solve the above technical problem, the present invention has a compounding material containing water, cement, silica carbure, blast furnace slag, gypsum, fine aggregate, coarse aggregate, and is formulated with a compressive strength of 120 MPa or more at a low water-binding ratio of 20% by weight or less. As a method for maximizing the strength expression of the designed ultra-high strength concrete, the following method is provided.

첫째, 초고강도 콘크리트 배합에서 슬럼프 플로우를 850±50mm 수준으로 배합설계하는 것을 통해 초고강도 콘크리트의 강도발현을 극대화하고자 한다.First, the design of the slump flow at the level of 850 ± 50mm is used to maximize the strength expression of the super high strength concrete.

둘째, 초고강도 콘크리트 배합에서 공기량을 1.0~2.0%로 배합설계하는 것을 통해 초고강도 콘크리트의 강도발현을 극대화하고자 한다.Second, we will maximize the strength expression of ultra high strength concrete by designing the air volume at 1.0 ~ 2.0% in the ultra high strength concrete mix.

셋째, 초고강도 콘크리트 비빔에서 먼저 굵은 골재와 실리카퓸을 투입하여 20~40초 동안 건비빔한 후 다른 배합재료를 투입하여 비빔하는 것을 통해 초고강도 콘크리트의 강도발현을 극대화하고자 한다.Third, in the ultra-high-strength concrete bibeam, first, coarse aggregate and silica fume are used to dry the beam for 20 to 40 seconds, and then, by adding other compounding materials to the beam, to maximize the strength expression of the ultra-high strength concrete.

넷째, 초고강도 콘크리트 비빔에서 맨 나중에 물을 투입하여 150~200초간 비빔한 후 200~400초 동안 비빔을 멈추어 그대로 놓아두는 정치(定置)과정을 거친 다음 다시 150~200초 동안 비빔하는 것을 통해 초고강도 콘크리트의 강도발현을 극대화하고자 한다.Fourth, in the super high-strength concrete bibimbly, water is added last and then beamed for 150 to 200 seconds, and then the beam is stopped for 200 to 400 seconds. To maximize the strength of high-strength concrete.

다섯째, 초고강도 콘크리트를 무다짐 타설하는 것을 통해 초고강도 콘크리트의 강도발현을 극대화하고자 한다.Fifth, it is intended to maximize the strength expression of ultra high strength concrete by compacting and pouring ultra high strength concrete.

여섯째, 초고강도 콘크리트를 타설한 후 14~28일 동안 습윤 양생한 다음 기건 양생하는 것을 통해 초고강도 콘크리트의 강도발현을 극대화하고자 한다.
Sixth, after pouring ultra-high strength concrete for 14-28 days of wet curing, and then curing by air to maximize the strength expression of ultra-high strength concrete.

본 발명에 따르면 다음과 같은 효과를 기대할 수 있다.According to the present invention, the following effects can be expected.

첫째, 초고강도 콘크리트에서 동일한 배합재료에 의한 동일한 배합설계를 가지고도 적절한 관리를 통해 초고강도 콘크리트의 강도발현을 극대화할 수 있다. 특히 비빔방법, 혼화제 첨가방법, 타설방법, 양생방법 등 관리방법이 간단하기 때문에 현장에 유리하게 적용할 수 있다.First, it is possible to maximize the strength expression of ultra high strength concrete through proper management even with the same mixing design by the same compounding material in ultra high strength concrete. In particular, the management method such as the bibimb method, admixture addition method, pouring method, curing method can be easily applied to the site.

둘째, 초고강도 콘크리트의 강도발현을 극대화시킬 수 있기 때문에 본 발명에 따라 초고강도 콘크리트를 관리하면서 초고강도 콘크리트 구조물을 구축한다면 강도 극대화에 따른 구조물의 안정성을 강화할 수 있다.
Second, because it is possible to maximize the strength expression of the ultra-high strength concrete, if the ultra-high strength concrete structure is constructed while managing the ultra high-strength concrete according to the present invention can increase the stability of the structure according to the maximum strength.

도 1은 슬럼프 플로어에 따른 초고강도 콘크리트의 강도특성을 보여준다.
도 2는 공기량에 따른 초고강도 콘크리트의 강도특성을 보여준다.
Figure 1 shows the strength characteristics of ultra-high strength concrete according to the slump floor.
Figure 2 shows the strength characteristics of ultra-high strength concrete according to the amount of air.

본 발명은 물, 시멘트, 실라카퓸, 고로슬래그, 석고, 잔골재, 굵은 골재를 포함하는 배합재료를 가지고 20중량% 이하의 낮은 물-결합재비로 120MPa 이상의 압축강도로 배합설계되는 초고강도 콘크리트에서, 동일한 배합재료에 의한 동일한 배합설계를 가지고도 초고강도의 강도발현을 극대화할 수 있는 6가지 관리조건을 제안한다. The present invention is the same in ultra-high strength concrete, which is designed to be formulated with a compressive strength of 120 MPa or more at a low water-binding ratio of 20% by weight or less, with a blending material comprising water, cement, silica carbure, blast furnace slag, gypsum, fine aggregates and coarse aggregates. Six management conditions are proposed to maximize the strength expression of ultra high strength even with the same mixing design.

아래 [실시예]에서는 6가지 관리조건 각각에 대한 극초고강도 콘크리트의 압축강도 향상효과를 확인하였다. 이에 따라 6가지 관리조건 각각은 초고강도 콘크리트의 강도발현을 극대화시킬 수 있는 방안이 될 것이며, 나아가 6가지 관리조건을 함께 적용한다면 초고강도 콘크리트의 강도발현을 더욱 상승시킬 수 있을 것으로 기대된다. 특히 6가지 관리조건은 200MPa 이상의 극초고강도 콘크리트로 배합설계되는 경우에 유리하게 적용할 수 있다.In the following [Example], the compressive strength improvement effect of the ultra-high strength concrete for each of the six management conditions was confirmed. Therefore, each of the six management conditions will be a way to maximize the strength expression of ultra-high strength concrete, and if the six management conditions are applied together, it is expected that the strength expression of the ultra-high strength concrete can be further increased. In particular, the six management conditions can be advantageously applied in the case of mixing design of ultra-high strength concrete of 200MPa or more.

(1)사전 건비빔(1) dictionary gunbi beam

콘크리트 믹서에서 배합하기 전에 배합재료 중에 굵은 골재와 실리카흄을 제일 먼저 넣고 20~40초 동안 건비빔을 실시한 후에 다른 배합재료를 투입하여 비빔한다. 이는 골재 표면에 실리카흄을 고르게 분산 코팅시키는 효과를 통해 천이대(시멘트 경화체와 골재의 경계면)의 포졸란 반응을 증진시켜 골재와 시멘트 페이스트 간의 부착력 증진에 도움을 주기 위함인데, 실제 [실시예]에서 30초 동안 건비빔을 한 결과 압축강도의 상승효과가 확인되었다.Before mixing in the concrete mixer, put the coarse aggregate and silica fume first in the compounding material, perform the dry beam for 20 to 40 seconds, and then add another compounding material to the beam. This is to improve the adhesion between the aggregate and cement paste by enhancing the pozzolanic reaction of the transition zone (the cement hardened body and the aggregate interface) through the effect of uniformly dispersing and coating silica fume on the aggregate surface. As a result of the dry beam for a second, the synergistic effect of the compressive strength was confirmed.

(2)중간 정치(定置, Stationing)(2) Stationing

콘크리트 믹서에서 나머지 배합재료를 투입하여 건비빔한 후 맨 나중에 물을 투입하여 배합할 때, 물을 투입하여 150~200초간 비빔한 후 200~400초 동안 비빔을 멈추어 그대로 놓아두는 정치(定置)과정을 거친 다음에 다시 150~200초 동안 비빔한 것을 배출토록 한다. 이는 초기 수화반응을 촉진시키고 콘크리트의 충전성 향상을 도모하기 위함이며, 실제 [실시예]에서 정치과정을 거칠 때 압축강도의 상승효과가 확인되었다.In the concrete mixer, the remaining compounding material is added to dry and then mixed with water, and then, after mixing with water, the water is added for 150 to 200 seconds to mix and then the beam is stopped for 200 to 400 seconds. After passing through it, let it discharge again for 150 ~ 200 seconds. This is to promote the initial hydration reaction and to improve the filling properties of the concrete, the synergistic effect of the compressive strength was confirmed when the static process in the actual Example.

(3)슬럼프 플로우 관리(3) slump flow management

초고강도 콘크리트의 슬럼프 플로우는 강도와 밀접한 관계가 있다. 즉, 높은 슬럼프 플로우를 가질수록 충전성 측면에서 유리하게 작용한다. 이를 감안하여 본 발명에서는 850±50mm 수준의 슬럼프 플로우를 제안하는데, 이보다 작으면 충전성이 떨어져 강도저하가 우려되고 이보다 크면 재료분리가 발생한다. 실제 [실시예]에서 200MPa의 극초고강도 콘크리트 배합에서 슬럼프 플로우와 강도의 관계를 확인한 결과, 850±50mm 수준에서 가장 강도발현이 높게 나타났다. 한편 슬럼프 플로우는 콘크리트 배합설계에 영향을 미치지 않는 각종 혼화제(감수제, 유동화제 등)의 첨가량을 적절히 조절하는 것으로 관리할 수 있다. The slump flow of ultra high strength concrete is closely related to strength. In other words, the higher the slump flow, the more advantageous it is in terms of filling. In view of this, the present invention proposes a slump flow of 850 ± 50mm level, but if smaller than this, the filling property is deteriorated and the strength decreases. In actual [Example], the relationship between the slump flow and the strength in the ultra-high strength concrete mixture of 200MPa was found, and the strength expression was the highest at the level of 850 ± 50mm. On the other hand, the slump flow can be managed by appropriately adjusting the amount of various admixtures (reducing agents, fluidizing agents, etc.) that do not affect the concrete mix design.

(4)공기량 관리(4) air volume management

공기량 2.0% 이하로 관리한다. 공기량은 강도와 반비례하는 현상을 보이기 때문에 공기량이 작을수록 강도에 유리하므로 이를 고려한 결과이다. 실제 [실시예]에서 200MPa의 극초고강도 콘크리트 배합에서 공기량과 강도의 관계를 확인한 결과, 2.0% 이하에서 강도발현이 높게 나타났다. 공기량은 콘크리트 배합설계에 영향을 미치지 않는 각종 혼화제(기포제, 소포제 등)의 첨가량을 적절히 조절하는 것으로 관리할 수 있다.  Manage at less than 2.0% of air volume. Since the air amount is inversely proportional to the strength, the smaller the air amount is, the better the strength is. In actual examples, the relationship between the amount of air and the strength of the ultra-high strength concrete mixture of 200 MPa was confirmed. The amount of air can be managed by appropriately adjusting the amount of various admixtures (foaming agent, antifoaming agent, etc.) that do not affect the concrete mix design.

(5)무다짐 타설(5) compaction casting

유동성이 좋다면 무다짐 타설한다. 바이브레이터를 이용한 진동 다짐을 할 경우 재료분리나 공기량 증가 등을 유발하여 강도저하를 초래할 수 있다. 실제 [실시예]에서 확인할 결과 진동다짐 타설보다 무다짐 타설에서 강도발현이 더 좋았다. 특히 앞서 살펴본 슬럼프 플로우의 관리를 통해 850±50mm의 슬럼프 플로우를 가지도록 설계한다면 유동성이 좋으므로, 무다짐 타설이 가능해진다.If the fluidity is good, compaction is poured. Vibration compaction using a vibrator may cause material separation or increase of air volume, resulting in a decrease in strength. As a result of confirming in the [Example], the strength expression was better in the compaction pour than the vibration compaction pour. In particular, if the slump flow is designed to have a slump flow of 850 ± 50 mm, the fluidity is good, so compaction can be poured.

(6)습윤 양생(6) wet curing

초고강도 콘크리트를 타설한 후 14~28일 동안 습윤 양생한 다음 기건 양생한다. 초고강도 콘크리트는 낮은 물-결합재비로 인해 내부 수분의 건조가 발생할 경우 수화반응에 필요한 물의 양이 모자랄 수 있으므로 수화반응이 활발히 일어나는 시기에는 내부 수분의 증발을 막을 필요가 있는데, 본 발명에서는 타설 후 14~28일간 습윤 양생을 할 것을 제안한다. 하지만 너무 장기간 동안 습윤 양생을 유지할 경우 오히려 강도 저하가 될 수 있으므로 14~28일 동안이 적절하다.
After pouring super high-strength concrete, it is wet curing for 14 ~ 28 days and then air curing. Ultra high-strength concrete is required to prevent the evaporation of internal moisture when the hydration reaction is active, because the amount of water required for the hydration reaction may be insufficient when the internal moisture is dried due to the low water-bonding material ratio, in the present invention Suggest 14 to 28 days of wet curing. However, if you maintain the wet curing for too long, the strength may be rather low, so 14 to 28 days is appropriate.

이하에서는 실시예에 의거하여 본 발명에 따른 관리조건에 의한 초고강도 콘크리트의 강도특성을 살펴본다. 다만, 하기의 실시예는 본 발명을 예시하기 위한 것일 뿐이며, 본 발명의 범위가 이로써 한정되는 것은 아니다.
Hereinafter, look at the strength characteristics of ultra-high strength concrete by the management conditions according to the present invention based on the embodiment. However, the following examples are only for illustrating the present invention, and the scope of the present invention is not limited thereto.

[실시예] 관리조건에 따른 초고강도 콘크리트의 강도특성[Example] Strength Characteristics of Ultra High Strength Concrete According to Management Conditions

1. 시험방법1. Test Method

아래 200MPa 초고강도 콘크리트 배합비를 동일하게 사용하여 각 시험변수별로 강도에 대한 영향을 파악하였다. 각각의 시험변수를 제외하고 다른 조건을 모두 동일하게 하여 시험하였다.The effect of strength on each test variable was determined by using the same 200MPa ultra-high strength concrete mixing ratio. Except for each test variable, all other conditions were tested under the same conditions.

초고강도 콘크리트 배합Ultra High Strength Concrete W/BW / B S/aS / a Unit Weight (kg/m3)Unit Weight (kg / m 3 ) WW OPCOPC Silica FumeSilica fume Blast Furnace SlagBlast furnace slag GypsumGypsum SandSand GravelGravel 12.5%12.5% 35%35% 150150 660660 240240 240240 6060 392392 736736

2. 시험결과2. Test result

(1)비빔조건에 따른 초고강도 콘크리트의 강도특성(1) Strength characteristics of ultra high strength concrete according to bibeam conditions

비빔조건을 달리한 초고강도 콘크리트의 강도특성은 아래 [표 2]와 같이 나타냈다. 보는 바와 같이 굵은 골재와 실리카퓸을 먼저 건비빔한 경우에서 압축강도가 향상된 것을 확인할 수 있다.The strength characteristics of super high strength concrete with different beam conditions are shown in [Table 2] below. As can be seen it can be seen that the compressive strength is improved when the coarse aggregate and silica fume first.

비빔조건에 따른 초고강도 콘크리트의 강도특성Strength Characteristics of Ultra-High Strength Concrete According to Bibeam Conditions 구분division 압축강도 (MPa)Compressive strength (MPa) 재령 7일7 days a year 재령 28일28 days old 재령 91일91 days of age 일반 건비빔General Gunbi Beam 150.4 150.4 184.5 184.5 198.7 198.7 굵은 골재 및 Coarse aggregate and 실리카흄Silica fume 건비빔 30초 선행 Gunbi Beam 30 Seconds Ahead 155.8 155.8 194.4 194.4 207.1 207.1

(2)정치여부에 따른 초고강도 콘크리트의 강도특성(2) Strength characteristics of ultra high strength concrete according to politics

물을 배합하는 과정에서 정치여부에 따른 초고강도 콘크리트의 강도특성은 아래 [표 3]와 같이 나타냈다. 보는 바와 같이 중간 정치과정을 거친 경우에서 압축강도가 향상된 것을 확인할 수 있다.The strength characteristics of the ultra-high strength concrete according to the static state in the process of mixing water are shown in the following [Table 3]. As can be seen, the compressive strength is improved in the case of intermediate fixing process.

정치여부에 따른 초고강도 콘크리트의 강도특성Strength Characteristics of Ultra-High Strength Concrete According to Fixation 구분division 압축강도 (MPa)Compressive strength (MPa) 재령 7일7 days a year 재령 28일28 days old 재령 91일91 days of age 정치 無Politics 144.1144.1 170.3170.3 191.6 191.6 180초 비빔 후 300초 정치한 다음 180초 비빔180 seconds, then 300 seconds, then 180 seconds 147.3147.3 174.9174.9 197.1 197.1

(3)슬럼프 플로우에 따른 초고강도 콘크리트의 강도특성(3) Strength characteristics of ultra high strength concrete according to slump flow

슬럼프 플로우에 변화를 주면서 초고강도 콘크리트의 강도를 평가할 결과 도 1과 같이 나타냈다. 보는 바와 같이 슬럼프 플로우가 800~900mm에서 200MPa 이상의 압축강도를 나타내고 그 이하에서는 200MPa를 넘지 못하는 것을 확인할 수 있다.As a result of evaluating the strength of the ultra-high strength concrete while changing the slump flow is shown in FIG. As can be seen, the slump flow shows a compressive strength of 200 MPa or more at 800 to 900 mm and below 200 MPa.

(4)공기량에 따른 초고강도 콘크리트의 강도특성(4) Strength characteristics of ultra high strength concrete according to air volume

공기량에 변화를 주면서 초고강도 콘크리트의 강도를 평가할 결과 도 2과 같이 나타냈다. 보는 바와 같이 공기량이 2%를 초과할 수록 압축강도가 크게 떨어지는 것을 확인할 수 있다.As a result of evaluating the strength of the ultra-high strength concrete while changing the amount of air is shown in FIG. As can be seen it can be seen that the compressive strength is greatly reduced as the amount of air exceeds 2%.

(5)타설방법에 따른 초고강도 콘크리트의 강도특성(5) Strength characteristics of ultra high strength concrete by pouring method

타설방법에 따른 초고강도 콘크리트의 강도특성은 아래 [표 4]와 같이 나타냈다. 보는 바와 같이 진동다짐보다 무다짐에서 강도발현이 크게 되는 것을 알 수 있다.Strength characteristics of the super high strength concrete according to the pouring method are shown in the following [Table 4]. As can be seen, the strength expression is greater at the compaction than the vibration compaction.

타설방법에 따른 초고강도 콘크리트의 강도특성Strength Characteristics of Ultra High Strength Concrete According to the Placing Method 구 분division 압축강도 (MPa)Compressive strength (MPa) 재령 7일7 days a year 재령 28일28 days old 재령 91일91 days of age 진동다짐Vibration 150.8 150.8 178.0 178.0 192.5 192.5 무다짐Compaction 153.2 153.2 187.2 187.2 201.7 201.7

(6)양생방법에 따른 초고강도 콘크리트의 강도특성(6) Strength characteristics of ultra high strength concrete according to curing method

양생방법에 따른 초고강도 콘크리트의 강도특성은 아래 [표 5]와 같이 나타냈다. 보는 바와 같이 수중양생 14일 진행할 때 압축강도가 가장 크게 발현된 것을 확인할 수 있다.The strength characteristics of the super high strength concrete according to the curing method are shown in the following [Table 5]. As you can see it can be seen that the compressive strength is the greatest expression when 14 days under water curing.

양생방법에 따른 초고강도 콘크리트의 강도특성Strength Characteristics of Ultra High Strength Concrete According to Curing Methods 수중양생 기간Underwater Curing Period 재령 91일 압축강도 (MPa)91-day compressive strength (MPa) 기건Air 179.6179.6 수중양생 3일Underwater Curing 3 Days 191.4191.4 수중양생 7일Underwater Curing 7 Days 202.5202.5 수중양생Underwater Curing 14일 14 days 212.0212.0 수중양생Underwater Curing 28일 28th 211.9211.9 수중양생 91일91 days of underwater curing 189.2189.2

Claims (8)

물, 시멘트, 실라카퓸, 고로슬래그, 석고, 잔골재, 굵은 골재를 포함하는 배합재료를 가지고 20중량% 이하의 낮은 물-결합재비로 120MPa 이상의 압축강도로 배합설계되는 초고강도 콘크리트의 강도발현을 극대화하기 위한 방법으로서,
먼저 굵은 골재와 실리카퓸을 투입하여 20~40초 동안 건비빔한 후 다른 배합재료를 투입하여 비빔하는 것을 특징으로 하는 강도발현의 극대화를 위한 초고강도 콘크리트의 관리방법.
Maximize the strength expression of ultra-high strength concrete that is formulated with a compressive strength of 120MPa or more with a blending material containing water, cement, silica carbure, blast furnace slag, gypsum, fine aggregates and coarse aggregates with a low water-binding ratio of 20% by weight or less. As a method for
First, coarse aggregates and silica fumes are added to dry beam for 20 to 40 seconds, and then other compounding materials are added to the beam to super-high strength concrete management method for maximizing strength expression.
물, 시멘트, 실라카퓸, 고로슬래그, 석고, 잔골재, 굵은 골재를 포함하는 배합재료를 가지고 20중량% 이하의 낮은 물-결합재비로 120MPa 이상의 압축강도로 배합설계되는 초고강도 콘크리트의 강도발현을 극대화하기 위한 방법으로서,
맨 나중에 물을 투입하여 150~200초간 비빔한 후 200~400초 동안 비빔을 멈추어 그대로 놓아두는 정치(定置)과정을 거친 다음 다시 150~200초 동안 비빔하는 것을 특징으로 하는 강도발현의 극대화를 위한 초고강도 콘크리트의 관리방법.
Maximize the strength expression of ultra-high strength concrete that is formulated with a compressive strength of 120MPa or more with a blending material containing water, cement, silica carbure, blast furnace slag, gypsum, fine aggregates and coarse aggregates with a low water-binding ratio of 20% by weight or less. As a method for
Lastly, water is added for 150 to 200 seconds, and then the beam is stopped for 200 to 400 seconds. Management method of ultra high strength concrete.
물, 시멘트, 실라카퓸, 고로슬래그, 석고, 잔골재, 굵은 골재를 포함하는 배합재료를 가지고 20중량% 이하의 낮은 물-결합재비로 120MPa 이상의 압축강도로 배합설계되는 초고강도 콘크리트의 강도발현을 극대화하기 위한 방법으로서,
슬럼프 플로우를 850±50mm 수준으로 배합설계하는 것을 특징으로 하는 강도발현의 극대화를 위한 초고강도 콘크리트의 관리방법.
Maximize the strength expression of ultra-high strength concrete that is formulated with a compressive strength of 120MPa or more with a blending material containing water, cement, silica carbure, blast furnace slag, gypsum, fine aggregates and coarse aggregates with a low water-binding ratio of 20% by weight or less As a method for
Management method of ultra-high strength concrete for maximizing strength expression, characterized by mixing design of slump flow to 850 ± 50mm level.
물, 시멘트, 실라카퓸, 고로슬래그, 석고, 잔골재, 굵은 골재를 포함하는 배합재료를 가지고 20중량% 이하의 낮은 물-결합재비로 120MPa 이상의 압축강도로 배합설계되는 초고강도 콘크리트의 강도발현을 극대화하기 위한 방법으로서,
공기량을 1.0~2.0%로 배합설계하는 것을 특징으로 하는 강도발현의 극대화를 위한 초고강도 콘크리트의 관리방법.
Maximize the strength expression of ultra-high strength concrete that is formulated with a compressive strength of 120MPa or more with a blending material containing water, cement, silica carbure, blast furnace slag, gypsum, fine aggregates and coarse aggregates with a low water-binding ratio of 20% by weight or less. As a method for
Ultra-high strength concrete management method for maximizing strength expression, characterized in that the mixing amount of air to 1.0 ~ 2.0%.
물, 시멘트, 실라카퓸, 고로슬래그, 석고, 잔골재, 굵은 골재를 포함하는 배합재료를 가지고 20중량% 이하의 낮은 물-결합재비로 120MPa 이상의 압축강도로 배합설계되는 초고강도 콘크리트의 강도발현을 극대화하기 위한 방법으로서,
초고강도 콘크리트를 무다짐 타설하는 것을 특징으로 하는 강도발현의 극대화를 위한 초고강도 콘크리트의 관리방법.
Maximize the strength expression of ultra-high strength concrete that is formulated with a compressive strength of 120MPa or more with a blending material containing water, cement, silica carbure, blast furnace slag, gypsum, fine aggregates and coarse aggregates with a low water-binding ratio of 20% by weight or less. As a method for
Management method of ultra-high strength concrete for maximization of strength expression, characterized by compacting and pouring ultra-high strength concrete.
물, 시멘트, 실라카퓸, 고로슬래그, 석고, 잔골재, 굵은 골재를 포함하는 배합재료를 가지고 20중량% 이하의 낮은 물-결합재비로 120MPa 이상의 압축강도로 배합설계되는 초고강도 콘크리트의 강도발현을 극대화하기 위한 방법으로서,
초고강도 콘크리트를 타설한 후 14~28일 동안 습윤 양생한 다음 기건 양생하는 것을 특징으로 하는 강도발현의 극대화를 위한 초고강도 콘크리트의 관리방법.
Maximize the strength expression of ultra-high strength concrete that is formulated with a compressive strength of 120MPa or more with a blending material containing water, cement, silica carbure, blast furnace slag, gypsum, fine aggregates and coarse aggregates with a low water-binding ratio of 20% by weight or less. As a method for
After the super-high strength concrete is poured for 14 to 28 days of wet curing, and then the curing method of ultra-high strength concrete for maximizing strength expression, characterized in that the curing.
물, 시멘트, 실라카퓸, 고로슬래그, 석고, 잔골재, 굵은 골재를 포함하는 배합재료를 가지고 20중량% 이하의 낮은 물-결합재비로 120MPa 이상의 압축강도로 배합설계되는 초고강도 콘크리트의 강도발현을 극대화하기 위한 방법으로서,
초고강도 콘크리트 배합에서 슬럼프 플로우를 850±50mm 수준으로 배합설계하는 관리조건;
초고강도 콘크리트 배합에서 공기량을 1.0~2.0%로 배합설계하는 관리조건;
초고강도 콘크리트 비빔에서 먼저 굵은 골재와 실리카퓸을 투입하여 20~40초 동안 건비빔한 후 다른 배합재료를 투입하여 비빔하는 관리조건;
초고강도 콘크리트 비빔에서 맨 나중에 물을 투입하여 150~200초간 비빔한 후 200~400초 동안 비빔을 멈추어 그대로 놓아두는 정치(定置)과정을 거친 다음 다시 150~200초 동안 비빔하는 관리조건;
초고강도 콘크리트를 무다짐 타설하는 관리조건;
초고강도 콘크리트를 타설한 후 14~28일 동안 습윤 양생한 다음 기건 양생하는 관리조건;
중에서 둘 이상의 관리조건을 선택하는 것을 특징으로 하는 강도발현의 극대화를 위한 초고강도 콘크리트의 관리방법.
Maximize the strength expression of ultra-high strength concrete that is formulated with a compressive strength of 120MPa or more with a blending material containing water, cement, silica carbure, blast furnace slag, gypsum, fine aggregates and coarse aggregates with a low water-binding ratio of 20% by weight or less. As a method for
Management conditions for mixing design of slump flow to the level of 850 ± 50mm in the mixing of high strength concrete;
Management condition to mix and design air volume at 1.0 ~ 2.0% in ultra high strength concrete mix;
In the super high-strength concrete bibeam, first, coarse aggregate and silica fume were added to dry the beam for 20 to 40 seconds, and then other materials were mixed to control the beam conditions.
Management conditions for the high-intensity concrete bibeam after the last injection of water for 150 to 200 seconds and then the beam is stopped for 200 to 400 seconds and then left to remain, and then beamed again for 150 to 200 seconds;
Management condition for compacting and pouring very high strength concrete;
Management conditions for wet curing for 14-28 days after pouring super-high strength concrete, followed by air curing;
Management method of ultra-high strength concrete for maximization of strength expression, characterized in that selecting two or more management conditions.
제1항 내지 제7항 중 어느 한 항에서,
상기 초고강도 콘크리트는, 200MPa 이상의 극초고강도 콘크리트로 배합설계되는 것을 특징으로 하는 강도발현의 극대화를 위한 초고강도 콘크리트의 관리방법.
8. The method according to any one of claims 1 to 7,
The ultra high-strength concrete is a super high strength concrete management method for maximizing strength expression, characterized in that the mixing design of ultra-high strength concrete of 200MPa or more.
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