KR20020045175A - Repair, Reinforce Method of Concrete Structure using High Strength Tension Material - Google Patents

Repair, Reinforce Method of Concrete Structure using High Strength Tension Material Download PDF

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KR20020045175A
KR20020045175A KR1020000074515A KR20000074515A KR20020045175A KR 20020045175 A KR20020045175 A KR 20020045175A KR 1020000074515 A KR1020000074515 A KR 1020000074515A KR 20000074515 A KR20000074515 A KR 20000074515A KR 20020045175 A KR20020045175 A KR 20020045175A
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South Korea
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concrete structure
bars
repair
mortar
mortar layer
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KR1020000074515A
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Korean (ko)
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조대연
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조대연
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    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04GSCAFFOLDING; FORMS; SHUTTERING; BUILDING IMPLEMENTS OR AIDS, OR THEIR USE; HANDLING BUILDING MATERIALS ON THE SITE; REPAIRING, BREAKING-UP OR OTHER WORK ON EXISTING BUILDINGS
    • E04G23/00Working measures on existing buildings
    • E04G23/02Repairing, e.g. filling cracks; Restoring; Altering; Enlarging
    • E04G23/0218Increasing or restoring the load-bearing capacity of building construction elements
    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04GSCAFFOLDING; FORMS; SHUTTERING; BUILDING IMPLEMENTS OR AIDS, OR THEIR USE; HANDLING BUILDING MATERIALS ON THE SITE; REPAIRING, BREAKING-UP OR OTHER WORK ON EXISTING BUILDINGS
    • E04G21/00Preparing, conveying, or working-up building materials or building elements in situ; Other devices or measures for constructional work
    • E04G21/12Mounting of reinforcing inserts; Prestressing

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  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Mechanical Engineering (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Working Measures On Existing Buildindgs (AREA)

Abstract

PURPOSE: A process for repairing/reinforcing a concrete structure is provided to attempt safety of the structure and to extend lifetime of the structure by making mortar layer introduced into sides to be repaired/reinforced to have sufficient tensile stress and anti-shear/bending force. CONSTITUTION: The process comprises, in addition to a common process of applying an adhesive on surface of a concrete structure to be repaired/reinforced, intersecting high strength tensioning bars(11) at right angles and introducing and curing mortar to form a mortar layer, tensioning the bars(11) as intersected then releasing the tension state of the bars(11) after completing curing of the bars to maintain the bars(11) having cured mortar layer under the tensioned state. On the surface, anchor bolts(12) are arranged at equal spaces. Each end of the bars(11) can be secured to the anchor bolts by fixing the end on a fixture plate moving by a hydraulic jack.

Description

고강도 긴장재를 이용한 콘크리트 구조물의 보수, 보강 방법{Repair, Reinforce Method of Concrete Structure using High Strength Tension Material}Repair, Reinforce Method of Concrete Structure using High Strength Tension Material}

본 발명은 고강도 긴장재를 이용한 콘크리트 구조물의 보수, 보강 방법에 관한 것으로, 특히 노화되거나 파손,하자가 발생하여 보수가 필요한 콘크리트 구조물을 보수, 보강하기 위하여 강선등의 고강도 긴장재를 사용하는 보수, 보강 방법에 관한 것이다.The present invention relates to a repair and reinforcement method of a concrete structure using a high-strength tension material, in particular a repair, reinforcement method using a high-strength tension material such as steel wire to repair and reinforce concrete structures that require repair due to aging, breakage, or defects. It is about.

일반적으로, 콘크리트 구조물을 사용 중 일부가 파손되거나, 시간이 경과함에 따른 노후화로 인해 강도가 약화되면, 파손 또는 강도가 약화된 면에 몰타르를타설하거나 또는 강판, 탄소섬유, 유리섬유 등을 설치한 후 몰타르를 타설하는 방법으로 보수 또는 보강을 하여 콘크리트 구조물의 내용연수를 연장시킨다.In general, when some of the concrete structure is damaged or its strength is weakened due to aging over time, it is necessary to cast mortar or install steel, carbon fiber, glass fiber, etc. on the damaged or weakened surface. After that, repair or reinforce the mortar to extend the useful life of the concrete structure.

보수, 보강 방법의 또 다른 예로는 보수, 보강하고자 하는 면에 스텐레스 스틸 와이어 메쉬를 설치한 후 몰타르로 양생하는 방법도 있다.Another example of the repair and reinforcement method is to install a stainless steel wire mesh on the surface to be repaired and reinforcement, and then to cure it in mortar.

그러나 이러한 보수, 보강 방법은 단순히 파손된 면이나 강도가 약화된 면을 몰타르를 덧발라 두껍게 하는 정도에 불과한 것이어서, 보강된 몰타르에 충분한 인장응력( 引張應力), 전단억제력, 휨 억제력을 기대할 수 없었다.However, these repair and reinforcement methods are merely to thicken the damaged or weakened surface by applying mortar, so that sufficient tensile stress, shear inhibition, and bending restraining force could not be expected for the reinforced mortar. .

따라서, 보수, 보강에 많은 비용이 소요되었음에도 불구하고 그 효과가 오래 지속Therefore, the effect lasts for a long time despite the high cost of repair and reinforcement.

되지 못하여 실질적으로 콘크리트 구조물의 내용연수를 연장시키는 효과가 미미한As a result, the effect of extending the useful life of concrete structures is insignificant.

실정이다.It is true.

또한, 대한민국 공개특허공보 공개번호 특 1999-24271호를 보면 이는 "보강하여야 할 콘크리트 구조물의 일측면을 그라인딩 기구에 의하여 면처리 작업을 행하는 면처리공정과, 상기 면처리공정에 의해 면처리된 콘크리트 구조물의 면에 있는 먼지를 제거하는 먼지제거 공정과, 상기 먼지제거공정에서 먼지가 제거된 면에 에폭시 접착제를 도포하는 에폭시 접착제 도포공정과, 상기 에폭시 접착제 도포공정에 의해 에폭시 접착제가 도포된 면에 고정용 앵커핀으로 스텐레스 스틸 와이어 메쉬를 고정시키는 스텐레스 스틸 와이어 메쉬 고정 공정과, 상기 스텐레스 스틸 와이어 메쉬고정공정에서 콘트리트 구조물의 일측면에 고정된 스텐레스 스틸 와이어 메쉬에 보강용 몰타르를 도포하여 몰타르층을 형성하는 몰타르 도포공정으로 이루어진 콘크리트 구조물의 보강 공법"에 관한 것으로 이에 의하여 콘크리트 구조물의 보강 강도를 장기간 동안 유지할수 있음과 동시에 콘크리트 구조물을 비교적 용이하고 저렴하게 보강할수 있다는 효과가 있는 것이다.In addition, Korean Patent Laid-Open Publication No. 1999-24271 discloses that "a surface treatment process for performing a surface treatment operation by a grinding mechanism on one side of a concrete structure to be reinforced, and concrete surface treated by the surface treatment process A dust removal step of removing dust on the surface of the structure, an epoxy adhesive applying step of applying an epoxy adhesive to a surface from which dust is removed in the dust removing step, and a surface coated with the epoxy adhesive by the epoxy adhesive applying step The stainless steel wire mesh fixing process of fixing the stainless steel wire mesh with fixing anchor pins, and the reinforcing mortar is applied to the stainless steel wire mesh fixed to one side of the concrete structure in the fixing process of the stainless steel wire mesh. Concrete structure consisting of mortar coating process to form Water reinforcement method "and thereby it is possible to maintain the reinforcement strength of the concrete structure for a long time and at the same time has the effect that the concrete structure can be reinforced relatively easily and inexpensively.

반면에 이러한 스텐레스 스틸 와이어 메쉬에 몰타르층이 도포된 상태에서는 스텐레스 스틸 와이어 메쉬가 단순히 매설되어 있는 상태이므로 스텐레스 스틸 와이어의 강도가 보수층의 인장응력 증진과 충분한 전단 억제력, 휨 억제력을 얻기 어렵게 되는 문제점이 있는 것이다.On the other hand, in the state where the mortar layer is applied to the stainless steel wire mesh, the stainless steel wire mesh is simply embedded, so that the strength of the stainless steel wire becomes difficult to obtain the tensile stress of the repair layer, sufficient shear restraint, and bending restraint. It is.

본 발명은 상기와 같은 종래의 문제점을 해결하기 위해 발명한 것으로, 본 발명의 목적은 콘크리트 구조물을 보수, 보강할 때, 상기 보수, 보강하려는 면에 타설되어 양생되는 몰타르가 긴장된 고강도 긴장재에 의하여 충분한 인장응력과 전단 억제력, 휨억제력을 가질 수 있도록 하는 고강도 긴장재를 이용한 콘크리트 구조물의 보수, 보강방법을 제공함에 있다.The present invention has been invented to solve the conventional problems as described above, the object of the present invention is sufficient by the high-strength tension material is a mortar is stiffened by curing on the surface to repair, reinforcement, when repairing, reinforcing the concrete structure The present invention provides a method for repairing and reinforcing concrete structures using high-strength tension members to have tensile stress, shear restraint, and flexural restraint.

도 1은 본 발명에 의한 보수, 보강 공정을 도시한 개략도.1 is a schematic diagram showing a repair and reinforcement process according to the present invention.

도 2는 본 발명의 보수, 보강 방법에 의하여 시공된 콘크리트 구조물의 단면도.Figure 2 is a cross-sectional view of the concrete structure constructed by the repair, reinforcement method of the present invention.

*도면의 주요 부분에 대한 부호의 설명** Description of the symbols for the main parts of the drawings *

10 : 콘크리트 구조물 11 : 고강도 긴장재10 concrete structure 11 high-strength tension material

12 : 앵커볼트 13 : 몰타르12: anchor bolt 13: Maltar

이러한 본 발명은 콘크리트 구조물의 보수, 보강하려는 면을 깨끗이 정리하고 접착제를 도포한 다음, 앵커볼트를 설치하고 고강도 긴장재를 앵커볼트에 걸고 가로 세로로 직교시킨 상태로 한 다음 긴장력을 주어 정착시키며, 이후 보강용 몰타르를 타설 양생하여 몰타르층을 경화시킨한 후, 상기 고강도 긴장재의 긴장력을 해제시켜 줌으로써 고강도 긴장재가 긴장상태로 남아 있도록 하여 몰타르층과 결합됨에 따라 보수층의 인장응력, 전단 억제력 및 휨억제력이 상당한 수준으로 유지되도록 함을 특징으로 한다.The present invention is to clean the surface to be repaired, reinforced concrete structure and apply the adhesive, then install the anchor bolt and the high-strength tension material to the anchor bolt to be orthogonal to vertically and then settled by giving a tension force, after After curing the reinforcing mortar to harden the mortar layer, by releasing the tension force of the high-strength tension material so that the high-strength tension material remains in tension, and combined with the mortar layer, the tensile stress, the shear suppression force, and the bending suppression force of the repair layer are increased. Characterized by maintaining a significant level.

이에 따라 콘크리트 구조물의 안전을 기하고 내용연수를 연장시키는 효과가 있다.Accordingly, the safety of the concrete structure and there is an effect to extend the service life.

상기와 같은 본 발명의 구성 및 작용을 첨부한 도면에 의거 상세히 설명하면 다음과 같다.Referring to the configuration and operation of the present invention as described above in detail as follows.

도 1은 본 발명에 의한 보수, 보강 공정을 도시한 개략도이고, 도 2는 본 발명의 보수, 보강 방법에 의하여 시공된 콘크리트 구조물의 단면도이다.1 is a schematic diagram showing a repair and reinforcement process according to the present invention, Figure 2 is a cross-sectional view of a concrete structure constructed by the repair, reinforcement method of the present invention.

상기 도면에서와 같이 본 발명은 보수, 보강하려는 콘크리트 구조물(10)의 면을 깨끗이 정리한 후 접착제를 도포하고, 일정간격으로 앵커볼트(12)를 설치한다.As shown in the figure, the present invention cleans up the surface of the concrete structure 10 to be repaired and reinforced, and then applies an adhesive and installs the anchor bolts 12 at regular intervals.

이후, 고강도 긴장재(11)를 가로와 세로로 배열하고 상기 고강도 긴장재(11)의 각 단부를 예를 들면 수압잭( Hydraulic Jack )에 의하여 이동되는 가동 정착판에 고정시키고 당겨 줌으로써 긴장시킨 상태에서 앵커볼트(12)에 고정한다.Thereafter, the high-strength tension member 11 is arranged horizontally and vertically, and each end of the high-strength tension member 11 is anchored in a tensioned state by being fixed and pulled to a movable fixing plate moved by, for example, a hydraulic jack. Fix it to the bolt (12).

상기 고강도 긴장재(11)는 다수 강선을 연선으로 한 것으로, 고강도 고성능강, 스텐레스강, 클레드강, 아라미드 섬유 등 여러 종류의 고강도 긴장재(11)를 사용할수 있으나, 콘크리트 구조물(10)의 중요도, 진단성격, 경제성 등을 검토하여 선택, 시공한다.The high-strength tension member 11 is made of a plurality of steel wire stranded, high-strength high-performance steel, stainless steel, clad steel, aramid fibers can be used a variety of high-strength tension member 11, but the importance of the concrete structure 10, Examine the diagnosis characteristics and economic feasibility and select and construct.

아울러, 상기한 예에서는 유압잭을 이용한 긴장방법을 설명하였으나, 고강도 긴장재(11)의 긴장을 위하여 기계식 방법, 화학식 방법, 전기식 방법, 프리플렉스방법 등 여러 방법 중 어느 한 방법을 선택하여 긴장시키면 된다.In addition, in the above example, the tension method using the hydraulic jack has been described, but the tension of the high-strength tension member 11 may be selected by any one of various methods such as a mechanical method, a chemical formula method, an electrical method, and a preflex method.

또한, 고강도 긴장재(11)가 직교로 긴장 정착된 위에 몰타르를 타설하여 몰타르층(13)을 형성하고, 상기 몰타르층(13)이 양생되면 앵커볼트(12)에 긴장 정착된 고강도 긴장재(11)의 긴장을 완전 해제시키는 것이며, 이를 위하여 간단히 고강도 긴장재(11)의 양단을 절단하여 주는 것도 무방하다.In addition, the high-strength tension member 11 is placed on the orthogonal tension fixation to form a mortar layer 13 to form a mortar layer, and when the mortar layer 13 is cured, the high-strength tension member 11 is tension-fixed to the anchor bolt 12 It is to completely release the tension, for this purpose simply cut both ends of the high-strength tension material (11).

아울러, 상기 보강용 몰타르층(13)은 보수, 보강이 필요한 콘크리트 구조물(10)의 진단내용, 중요도, 경제성 등을 검토하여 일반 몰타르나 수지 또는 섬유계를 혼합한 특수 몰타르 중 어느 하나를 선정 시공하거나, 복합적으로 시공할 수 있다.In addition, the reinforcement mortar layer 13 is selected and constructed any one of the special mortar mixed with general mortar, resin or fiber based on the diagnosis content, importance, economics, etc. of the concrete structure 10 that needs repair and reinforcement Or it can be combined.

그리고 상기 고강도 긴장재(11)의 긴장을 풀어주면, 몰타르가 이미 양생되었기 때문에 고강도 긴장재(11)의 긴장상태가 완전 해제되지 않고 적당히 긴장된 상태로 유지되어 응력이 남아있게 되는 것이며, 이러한 응력은 몰타르층(13)에 압축응력을 주고, 이 압축응력은 콘크리트 구조물(10)의 사용에 따른 인장응력을 상쇄시키며, 전단 억제력을 강화하고 휨억제력을 얻게 되는 것이며, 고강도 긴장재(11)를 종, 횡방향으로 적정간격 배열하였기 때문에 네트(net)의 역할을 할수 있게 되어 몰타르층과의 결속력이 더욱 강화된다.And when the tension of the high-strength tension member 11 is released, since the mortar has already been cured, the tension state of the high-strength tension member 11 is not completely released and is maintained in a moderately tensioned state so that the stress remains. The compressive stress is imparted to (13), and this compressive stress cancels the tensile stress according to the use of the concrete structure (10), strengthens the shear restraint force, and obtains the bending restraining force. Since the proper intervals are arranged to act as a net (net), the bond with the mortar layer is further strengthened.

상기한 바와 같이 본 발명은 콘크리트 구조물의 보수, 보강될 면에 타설 양생되는 몰타르층이 충분한 인장응력과 함께 전단 및 휨 억제력을 갖게 되어 콘크리트 구조물을 바람직한 상태로 보수, 보강할수 있게 되는 것이어서 콘크리트 구조물의 안전을 기하고 내용연수를 연장시키는 효과가 있다.As described above, the present invention is that the mortar layer that is cured on the surface to be repaired and reinforced has a sufficient tensile stress and shear and bending restraint so that the concrete structure can be repaired and reinforced to a desired state. It has the effect of ensuring safety and extending the useful life.

Claims (1)

콘크리트 구조물(10)의 보수, 보강하려는 면을 깨끗이 정리하고 접착제를 도포한 다음, 고강도 긴장재(11)를 가로, 세로로 직교시킨 상태에서 보강용 몰타르를 타설 양생하여 몰타르층(14)을 경화시키도록 하는 공지의 방법에 있어서,After arranging the surface to be repaired and reinforced of the concrete structure 10 and applying an adhesive, the mortar layer 14 is cured by pouring curing mortar for reinforcement in a state where the high-strength tension member 11 is orthogonal to the horizontal and vertical. In the known method, 상기 고강도 긴장재(11)를 가로, 세로로 직교시킨 상태에서 긴장시키고, 양생완료후 고강도 긴장재(11)의 긴장 상태를 해제함으로써 양생된 몰타르층(14)의 고강도 긴장재(11)의 긴장 상태가 유지되도록 함을 특징으로 하는 고강도 긴장재를 이용한 콘크리트 구조물의 보수 보강 방법.The tension state of the high-strength tension member 11 of the cured mortar layer 14 is maintained by tensioning the high-strength tension member 11 in a horizontally or vertically orthogonal state, and releasing the tension state of the high-strength tension member 11 after completion of curing. Repair reinforcement method of a concrete structure using a high-strength tension material characterized in that.
KR1020000074515A 2000-12-08 2000-12-08 Repair, Reinforce Method of Concrete Structure using High Strength Tension Material KR20020045175A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100403397B1 (en) * 2001-03-15 2003-10-30 황대하 Repairing method of outdated concrete fabric of creek covered by lid
KR100718585B1 (en) * 2006-08-10 2007-05-15 한국건설기술연구원 Punching-shear strengthening method with externally bonded prestressed frp strips
CN104066908A (en) * 2011-12-06 2014-09-24 株式会社丸高工业 Peeling device

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06330586A (en) * 1993-05-24 1994-11-29 Mitsui Constr Co Ltd Reinforcement for concrete, and manufacture thereof
JPH0782709A (en) * 1993-09-14 1995-03-28 Oriental Constr Co Ltd Reinforcing method for concrete structure, employing hollow pc steel bar
JPH09291708A (en) * 1996-04-24 1997-11-11 Kyoryo Hozen Kk Reinforcing lattice material
KR19990024271A (en) * 1998-12-29 1999-03-25 유성권 Reinforcement structure and reinforcement method of concrete structure
JP2000265420A (en) * 1999-03-17 2000-09-26 Civil:Kk Covering net type rock-fall preventive construction method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06330586A (en) * 1993-05-24 1994-11-29 Mitsui Constr Co Ltd Reinforcement for concrete, and manufacture thereof
JPH0782709A (en) * 1993-09-14 1995-03-28 Oriental Constr Co Ltd Reinforcing method for concrete structure, employing hollow pc steel bar
JPH09291708A (en) * 1996-04-24 1997-11-11 Kyoryo Hozen Kk Reinforcing lattice material
KR19990024271A (en) * 1998-12-29 1999-03-25 유성권 Reinforcement structure and reinforcement method of concrete structure
JP2000265420A (en) * 1999-03-17 2000-09-26 Civil:Kk Covering net type rock-fall preventive construction method

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100403397B1 (en) * 2001-03-15 2003-10-30 황대하 Repairing method of outdated concrete fabric of creek covered by lid
KR100718585B1 (en) * 2006-08-10 2007-05-15 한국건설기술연구원 Punching-shear strengthening method with externally bonded prestressed frp strips
CN104066908A (en) * 2011-12-06 2014-09-24 株式会社丸高工业 Peeling device
CN104066908B (en) * 2011-12-06 2016-05-18 株式会社丸高工业 Stripping off device

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