JPH05306560A - Unbonding treated frp tension material - Google Patents

Unbonding treated frp tension material

Info

Publication number
JPH05306560A
JPH05306560A JP13787692A JP13787692A JPH05306560A JP H05306560 A JPH05306560 A JP H05306560A JP 13787692 A JP13787692 A JP 13787692A JP 13787692 A JP13787692 A JP 13787692A JP H05306560 A JPH05306560 A JP H05306560A
Authority
JP
Japan
Prior art keywords
layer
tension material
rubber
layers
frp
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP13787692A
Other languages
Japanese (ja)
Other versions
JP2783373B2 (en
Inventor
Takehiko Kato
武彦 加藤
Toshiyuki Kitsuta
敏之 橘田
Akira Iiizumi
章 飯泉
Hironobu Nishiyama
啓伸 西山
Kentaro Fujii
健太郎 藤井
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Concrete Industries Co Ltd
Kumagai Gumi Co Ltd
NIPPON PRESSED CONCRETE CO Ltd
Original Assignee
Nippon Concrete Industries Co Ltd
Kumagai Gumi Co Ltd
NIPPON PRESSED CONCRETE CO Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nippon Concrete Industries Co Ltd, Kumagai Gumi Co Ltd, NIPPON PRESSED CONCRETE CO Ltd filed Critical Nippon Concrete Industries Co Ltd
Priority to JP13787692A priority Critical patent/JP2783373B2/en
Publication of JPH05306560A publication Critical patent/JPH05306560A/en
Application granted granted Critical
Publication of JP2783373B2 publication Critical patent/JP2783373B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Abstract

PURPOSE:To minimize a friction loss coefficient during prestress introduction time by coating at least three layers out of four coating layers which comprise a first layer of an asphalt rubber, a second layer of butyl rubber, a third layer of protection paper and a fourth layer of waterproof paper in that order from inside. CONSTITUTION:An asphalt-group rubber is applied to the surface of an FRP- made tension material 10 as a first layer and covered, thereby forming a surface covering of the tension material. Then, a butyl-group rubber film is formed on the asphalt-group rubber as a second layer. Then, protection paper is rolled up as a third layer. Finally, waterproof tape is rolled up as a fourth layer. Furthermore, at least three layers are covered from inside in that order out of the four covering layers.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明はプレストレスコンクリー
ト(以下、PCという。)構造物に使用するためのアン
ボンド化表面処理を施したFRP緊張材に関するもので
ある。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an FRP tension material having an unbonded surface treatment for use in a prestressed concrete (hereinafter referred to as PC) structure.

【0002】[0002]

【従来技術とその問題点】PC構造物の構築方法には、
主として工場製品に適用されるプレテンション方式と、
現場打ちのPC構造物に適用されるポストテンション方
式とがある。ポストテンション方式は、現場でPC部材
にコンクリートを打設した後、PC緊張材にプレストレ
スを与えるものであり、大別して、予め、構造物にシ
ースを入れておき、プレストレス導入後シースとPC緊
張材の間にセメントミルクなどのグラウト材を注入して
構造物としての一体化を図る方法と、緊張材の表面に
グリース、被覆材などを用いてアンボンド処理を施した
PC緊張材に、コンクリート打設後、プレストレスを導
入してグラウト作業を省き、施工を簡略化する方法とが
ある。
2. Description of the Related Art The method for constructing a PC structure includes:
A pre-tension method mainly applied to factory products,
There is a post tension method applied to a PC structure cast in situ. The post-tension method is to apply prestress to the PC tension material after placing concrete on the PC member at the site, roughly classifying it into a sheath in advance in advance and introducing the prestress to the sheath and PC. A method of injecting grout material such as cement milk between the tension materials to integrate them as a structure, and a PC tension material that has been unbonded with grease or a covering material on the surface of the tension material, concrete After casting, there is a method of introducing prestress to omit grout work and simplify the construction.

【0003】アンボンド処理はPC鋼棒やPC鋼より線
などのPC鋼材に対して行われる。PC鋼棒の表面は滑
らかでストレートであるため、粘性のあるアスファルト
系の皮膜を施し、その上から滑りを良くするために、保
護紙などを被せている。また、アンボンドPC鋼より線
は、PC鋼より線の外周に防錆と潤滑性に優れたグリー
スを施し、ポリエチレン製などのシースで被覆してい
る。
The unbonding treatment is performed on PC steel materials such as PC steel rods and PC steel strands. Since the surface of the PC steel bar is smooth and straight, a viscous asphalt-based film is applied, and a protective paper or the like is covered on the PC steel bar to improve sliding. In addition, the unbonded PC stranded wire is coated with a sheath made of polyethylene or the like by applying grease having excellent rust prevention and lubricity to the outer periphery of the PC stranded wire.

【0004】このように、従来、PC緊張材としてPC
鋼材が使用されていたが、このPC鋼材は腐食性の点で
耐久性に問題がある。そこで最近、PC鋼材の代わり
に、炭素、アラミド、ガラスなどの繊維をプラスチック
で強化したFRP緊張材を使用する研究開発が行われて
いる。FRP緊張材は高強度かつ軽量で、耐食性にも優
れた材料であるが、現在、そのアンボンド化表面処理に
ついては何ら確立された方法は見出されていない。
As described above, as a conventional PC tension member, PC
Although a steel material was used, this PC steel material has a problem in durability in terms of corrosiveness. Therefore, in recent years, research and development have been conducted in which, instead of the PC steel material, an FRP tension material in which fibers such as carbon, aramid and glass are reinforced with plastic is used. The FRP tension material is a material having high strength and light weight and excellent corrosion resistance, but at present, no established method has been found for its unbonded surface treatment.

【0005】[0005]

【発明の目的】然して、本発明の目的はFRP緊張材に
対してアンボンド化表面処理法を確立することにある。
OBJECTS OF THE INVENTION It is therefore an object of the present invention to establish an unbonded surface treatment method for FRP tendons.

【0006】[0006]

【発明の概要】本発明のアンボンドFRP緊張材は、下
記被覆層のうち少なくとも3層を、内側からその順に被
覆してなることを特徴とするものである。 第1層:アスファルト系ゴム 第2層:ブチル系ゴム 第3層:保護紙 第4層:防水テープ
SUMMARY OF THE INVENTION The unbonded FRP tendon of the present invention is characterized in that at least three of the following coating layers are coated in that order from the inside. First layer: Asphalt rubber Second layer: Butyl rubber Third layer: Protective paper Fourth layer: Waterproof tape

【0007】[0007]

【発明の具体的説明】本発明においてFRP緊張材とし
ては、炭素繊維、アラミド繊維、ガラス繊維などをプラ
スチックで強化したFRP緊張材を用いる。
DETAILED DESCRIPTION OF THE INVENTION In the present invention, as the FRP tension material, an FRP tension material obtained by reinforcing carbon fiber, aramid fiber, glass fiber or the like with plastic is used.

【0008】FRP緊張材の表面には、第1層としてア
スファルト系ゴム、シリコンアスファルト系ゴムおよび
これに類するものを塗布、被覆して、緊張材の表面皮膜
を形成する。このため、FRP緊張材の表面に付着を増
すための異形加工が施されていても、上記ゴムを使用し
ているのでアンボンド化が可能となる。また、ガラス繊
維系のFRP緊張材に対しては、併せて、耐アルカリ性
を付与することができる。
As the first layer, asphalt rubber, silicon asphalt rubber and the like are applied and coated on the surface of the FRP tension material to form a surface film of the tension material. For this reason, even if the surface of the FRP tension material is modified to increase the adhesion, it can be unbonded because the rubber is used. In addition, alkali resistance can also be imparted to the glass fiber-based FRP tension material.

【0009】前記アスファルト系ゴムの上に、第2層と
してブチル系ゴムなど粘り気のあるゴムの皮膜を形成す
る。これはアスファルト系ゴムと同様に、異形加工材に
対する配慮と耐アルカリ性付与をするためである。
A film of viscous rubber such as butyl rubber is formed as a second layer on the asphalt rubber. This is because, like the asphalt rubber, consideration is given to the deformed material and alkali resistance is imparted.

【0010】次に第3層として、滑り性を付与するため
の保護紙を巻く。保護紙で巻くことにより、FRP緊張
材の周囲のコンクリートとの摩擦を低減することができ
る。保護紙を2重にすれば、摩擦を更に低減することも
可能である。
Next, as the third layer, a protective paper for imparting slipperiness is wound. By wrapping with protective paper, it is possible to reduce friction with the concrete around the FRP tendon. If the protective paper is doubled, it is possible to further reduce friction.

【0011】最後に第4層として、防水テープを巻く。
この防水テープは外部からの損傷保護の役目も果たす。
また、防水テープは作業性の点で、延性を有しているこ
とが望ましい。
Finally, a waterproof tape is wound as the fourth layer.
This waterproof tape also serves as a protection against external damage.
Further, it is desirable that the waterproof tape has ductility in terms of workability.

【0012】本発明のアンボンドFRP緊張材は、芯材
となるFRP緊張材の物理的および化学的性質に応じ
て、最適の被覆材を最適の順に、上記各層を組み合わせ
てアンボンド化表面処理を行うものである。例えば、炭
素繊維のように、耐アルカリ性に優れた繊維の場合に
は、第1層のアスファルト系ゴム及び/又は第2層のブ
チルゴムを省略してもよい。但し、炭素繊維系FRP緊
張材の表面は平滑ではないから、第2層のブチルゴムで
被覆した方が摩擦損失が低減するので、滑り性の点では
好ましい。
The unbonded FRP tension material of the present invention is subjected to an unbonded surface treatment by combining the above-mentioned layers in the optimal coating material in the optimal order according to the physical and chemical properties of the FRP tension material as the core material. It is a thing. For example, in the case of a fiber having excellent alkali resistance such as carbon fiber, the asphalt rubber of the first layer and / or the butyl rubber of the second layer may be omitted. However, since the surface of the carbon fiber-based FRP tension material is not smooth, it is preferable to coat it with the butyl rubber of the second layer because friction loss is reduced.

【0013】一方、ガラス繊維の場合は炭素繊維やアラ
ミド繊維と比べ、耐アルカリ性に劣るから、第1層のア
スファルト系ゴム及び/又は第2層のブチルゴムを必須
として、コンクリート中のアルカリ成分からFRP緊張
材を保護するものである。本発明のアンボンドFRP緊
張材は、上記被覆層のうち少なくとも3層を(炭素繊維
系FRP緊張材にあっては、少なくとも2層を)、内側
からその順に被覆するものである。
On the other hand, glass fiber is inferior in alkali resistance to carbon fiber and aramid fiber, so that the first layer of asphalt-based rubber and / or the second layer of butyl rubber is indispensable, and the alkali component in the concrete is used as FRP. It protects the tension material. The unbonded FRP tension material of the present invention covers at least three layers (at least two layers in the case of carbon fiber type FRP tension material) of the above coating layers in this order from the inside.

【0014】アンボンドFRP緊張材は、従来のアンボ
ンドPC鋼材と同じ方法によりPC構造物に用いられ、
プレストレスを導入される。続いて、本発明の好ましい
実施例を説明する。
Unbonded FRP tendons are used in PC structures in the same manner as conventional unbonded PC steel.
Prestress is introduced. Next, preferred embodiments of the present invention will be described.

【0015】[0015]

【実施例】本発明に係るアンボンド処理を施したガラス
繊維系のFRP緊張材について、以下のように摩擦損失
試験を行った。 〔試験方法〕下記表1に示すアンボンド化表面処理した
FRP緊張材を、コンクリート中に埋め込んだ試験体A
〜Dを製作し、これを図1に示す装置を用いて摩擦損失
試験を行った。なお、試験体Eは、コンクリート中にシ
ースの孔を設けてFRP緊張材の引張試験を行ったもの
であり、比較のためのものである。
EXAMPLE A friction loss test was conducted as follows for the glass fiber-based FRP tension material subjected to the unbonding treatment according to the present invention. [Test Method] Specimen A in which the unbonded surface-treated FRP tension material shown in Table 1 below was embedded in concrete.
To D were manufactured and subjected to a friction loss test using the apparatus shown in FIG. In addition, the test body E was prepared by performing a tensile test of the FRP tension material by providing a sheath hole in the concrete, and is for comparison.

【0016】図1において、アンボンド化表面処理した
FRP緊張材10を、コンクリート11中に埋め込んだ
試験体12の左右両側に、プレート13、13、荷重計
測用ロードセル14、14、およびプレート15、15
の順にセットし、片側から反力体となるラムチェア16
を介して、ジャッキ17を用いてFRP緊張材を緊張し
た。
In FIG. 1, plates 13 and 13, load measuring load cells 14 and 14, and plates 15 and 15 are provided on the left and right sides of a test body 12 in which an unbonded surface-treated FRP tension material 10 is embedded in concrete 11.
Set in the order of, and the ramchair 16 becomes a reaction force from one side.
The FRP tendon was tightened using the jack 17 via the.

【0017】このとき、緊張側の荷重と反対側(固定
側)の荷重を各荷重段階で同時に測定し、以下の式に従
って、FRP緊張材の摩擦損失係数λ(緊張材1m長当
たり)を求めた。 PX =P0 ×e-(μα +λL ) 〔但し、P0 :緊張端荷重、PX :固定端荷重、μ:角
変化1 rad当たりの摩擦係数(1/ rad)、α:角変化
( rad)、λ:緊張材1m当たりの摩擦損失係数( 1/
m )、L :緊張材長さ(m)である。〕 ここで、緊張材は直線配置であるため、α=0である。
よって、λ=−1/L ・ln(PX / P0 )となる。
At this time, the load on the tension side and the load on the opposite side (fixed side) are simultaneously measured at each load stage, and the friction loss coefficient λ (per 1 m length of the tension member) of the FRP tension member is calculated according to the following formula. It was P X = P 0 × e- ( μα + λL ) [where P 0 : tension end load, P X : fixed end load, μ: friction coefficient per 1 rad of angular change (1 / rad), α: angular change (Rad), λ: Friction loss coefficient per 1 m of tendon (1 /
m), L: Tension material length (m). ] Here, since the tension members are linearly arranged, α = 0.
Therefore, λ = −1 / L·ln (P X / P 0 ).

【0018】〔試験結果〕本発明に係る試験体A〜Dの
摩擦損失係数λは、表1に示すように試験体Eの摩擦損
失係数λと比較しても遜色なく、従来のアンボンドPC
鋼材とほぼ同じ値であった。
[Test Results] The friction loss coefficient λ of the test bodies A to D according to the present invention is comparable to the friction loss coefficient λ of the test body E as shown in Table 1, and the conventional unbonded PC is used.
It was almost the same value as steel.

【0019】[0019]

【表1】 試験体 アンボンド処理層 摩擦損失係数λ A ++++ 0.00545 (1/m) B +++++ 0.00512 C +++++ 0.00635 D +++ 0.00592 E 無 0.00491 (備考);アスファルト系ゴム、;ブチルゴム、;保護紙、;防水テー プTABLE 1 Specimen unbonded process layer of friction loss coefficient λ A ++++ 0.00545 (1 / m ) B +++++ 0.00512 C +++++ 0.00635 D +++ 0.00592 E No 0.00491 (Notes); asphalt rubber; butyl rubber; protective paper; waterproof Tape

【0020】[0020]

【発明の効果】本発明はFRP緊張材に対してアンボン
ド化表面処理を行うことにより、プレストレス導入時の
摩擦損失係数を小さくするとともに、表面を外的損傷か
ら保護することができる。また、アンボンド表面処理に
より、グラウト作業の手間がなくなり作業工程が短縮で
きるとともに、緊張端から固定端へ伝達する荷重の損失
を小さくでき、従来のアンボンドPC鋼材と同様にして
用いることができる。
INDUSTRIAL APPLICABILITY According to the present invention, by performing an unbonded surface treatment on the FRP tension material, the friction loss coefficient at the time of introducing prestress can be reduced and the surface can be protected from external damage. Further, the unbonded surface treatment eliminates the trouble of grout work, shortens the working process, and reduces the loss of the load transmitted from the tensioned end to the fixed end, and can be used in the same manner as the conventional unbonded PC steel material.

【図面の簡単な説明】[Brief description of drawings]

【図1】FRP緊張材を埋め込んだ試験体の摩擦損失係
数を測定した装置の概要図である。
FIG. 1 is a schematic diagram of an apparatus for measuring a friction loss coefficient of a test body in which a FRP tension material is embedded.

【符号の説明】[Explanation of symbols]

10 FRP緊張材 12 試験体 14 荷重計測用ロードセル 16 ラムチェア 17 ジャッキ 10 FRP tension material 12 Specimen 14 Load cell for load measurement 16 Ramchair 17 Jack

フロントページの続き (72)発明者 加藤 武彦 茨城県つくば市大字鬼ヶ窪字下山1043番1 株式会社熊谷組技術研究所内 (72)発明者 橘田 敏之 東京都新宿区津久戸町2番1号 株式会社 熊谷組東京本社内 (72)発明者 飯泉 章 千葉県松戸市松戸新田3の4 美野里ハイ タウン4の407 (72)発明者 西山 啓伸 東京都港区新橋1丁目8番3号 日本コン クリート工業株式会社内 (72)発明者 藤井 健太郎 千葉県習志野市実籾町4−1096−32Front page continuation (72) Inventor Takehiko Kato 1043-1, Shimoyama, Onigakushi, Tsukuba, Ibaraki Prefecture Kumagai Gumi Technical Research Institute Co., Ltd. Kumagai Gumi Tokyo Head Office (72) Inventor Akira Iizumi 4 3-4 Matsudo Nitta 3 Matsudo-shi, Chiba 4407 Minori High Town 4 407 (72) Inventor Hironobu Nishiyama 1-8-3 Shimbashi, Minato-ku, Tokyo Nippon Concrete Co., Ltd. Incorporated (72) Inventor Kentaro Fujii 4-1096-32 Mimomicho, Narashino City, Chiba Prefecture

Claims (2)

【特許請求の範囲】[Claims] 【請求項1】 下記被覆層のうち少なくとも3層を、内
側からその順に被覆してなるアンボンド処理を施したF
RP緊張材。 第1層:アスファルト系ゴム 第2層:ブチル系ゴム 第3層:保護紙 第4層:防水テープ
1. An unbonded F obtained by coating at least three layers of the following coating layers in that order from the inside.
RP tension material. First layer: Asphalt rubber Second layer: Butyl rubber Third layer: Protective paper Fourth layer: Waterproof tape
【請求項2】 下記被覆層のうち少なくとも2層を、内
側からその順に被覆してなるアンボンド処理を施した炭
素繊維系FRP緊張材。 第1層:アスファルト系ゴム及び/又はブチル系ゴム 第2層:保護紙 第3層:防水テープ
2. A carbon fiber-based FRP tension material obtained by unbonding at least two layers of the following coating layers in that order from the inside. First layer: Asphalt rubber and / or butyl rubber Second layer: Protective paper Third layer: Waterproof tape
JP13787692A 1992-04-30 1992-04-30 FRP tendon material with unbonded treatment Expired - Lifetime JP2783373B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP13787692A JP2783373B2 (en) 1992-04-30 1992-04-30 FRP tendon material with unbonded treatment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP13787692A JP2783373B2 (en) 1992-04-30 1992-04-30 FRP tendon material with unbonded treatment

Publications (2)

Publication Number Publication Date
JPH05306560A true JPH05306560A (en) 1993-11-19
JP2783373B2 JP2783373B2 (en) 1998-08-06

Family

ID=15208765

Family Applications (1)

Application Number Title Priority Date Filing Date
JP13787692A Expired - Lifetime JP2783373B2 (en) 1992-04-30 1992-04-30 FRP tendon material with unbonded treatment

Country Status (1)

Country Link
JP (1) JP2783373B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007063910A (en) * 2005-09-01 2007-03-15 Railway Technical Res Inst Deviation preventive guard of crosstie and crosstie with deviation preventive guard

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007063910A (en) * 2005-09-01 2007-03-15 Railway Technical Res Inst Deviation preventive guard of crosstie and crosstie with deviation preventive guard
JP4549262B2 (en) * 2005-09-01 2010-09-22 財団法人鉄道総合技術研究所 Ladder sleeper with escape guard

Also Published As

Publication number Publication date
JP2783373B2 (en) 1998-08-06

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