JPWO2003027416A1 - Structure reinforcement structure, reinforcement material, seismic isolation device, and reinforcement method - Google Patents

Abstract

A slit 5 penetrating the flat member 3 is provided at the joint between the square member 1 and the flat member 3. Both ends of the reinforcing member 7 a are passed through the slit 5 from the side surface 8 a side of the square member 1 and temporarily attached to the square member 1 with the adhesive 11. Next, both ends of the reinforcing member 7 b are passed through the slit 5 from the side surface 8 b side of the square member 1 and bonded to the reinforcing member 7 a with the adhesive 9. Further, both ends of the reinforcing member 7 c are passed through the slit 5 from the side surface 8 a side of the square member 1 and bonded to the reinforcing member 7 b with the adhesive 9.

Description

定着長ｓ＝ｂ−ａ内の帯状補強材１０１と柱１０５の平均せん断力をτとすると、

である。
式１、式２）より自由長ａを消去すると、張力１２１（ｑ）と平均せん断力τ、クラック幅１１７（ｄ）の間には、次の２次関係がある。

この関係は、最大クラック幅ｄ_ｍａｘ以下で２つの解ｑがあるが、大きいほうの解が先に実現するので、これを採用することにすると、ｑはクラック幅１１７（ｄ）に応じて、最大値ｑ_ｍａｘと最小値ｑ_ｍｉｎの間になる。

最小値ｑ_ｍｉｎに対応するクラック幅ｄ_ｍａｘは、

である。
クラック幅がｄ_ｍａｘを越えると、式３）は解を持たない。即ち、このようなメカニズムが成り立たなくなる。以上の関係から、クラック１１５を押し広げようとする力を帯状補強材１０１で分担する時の最大値ｑ_ｍａｘと最小値ｑ_ｍｉｎを求めて、上記のメカニズムを利用した構造補強を設計することができる。式４）から式６）の値は、柱１０５等の部材と帯状補強材１０１の間の接着力τ（平均せん断力）に比例する。
帯状補強材１０１としてポリエステルベルト９９等の安価で伸展性に優れた材料を用いた場合には、材料としてのヤング率はコンクリートの約１０分の１、鉄の約１００分の１である。従って、平均せん断力τの大きな接着剤１１３を用いて接着したとしても、クラック１１５を生じずに弾性的に部材に加わるせん断力を分担することは困難である。しかし、変形の小さい範囲内での補強効果を特に必要とする場合には、ポリエステルベルト等に樹脂を含浸させて補強材の剛性を高めた上で、エポキシ樹脂系の接着剤を用いる。
第２８図において、例えば、帯状補強材１０１が幅６４ｍｍ、厚さ４ｍｍのポリエステルベルト９９であり、柱１０５が、拘束長１２５がｂ＝３０ｃｍの鉄筋コンクリート柱であり、接着剤１１３として、トーヨーポリマー製のエポキシウレタン系接着剤ルビロンを用いるとする。このとき、平均せん断力τ＝１０ｋｇｆ／ｃｍ^２、帯状補強材１０１（ポリエステルベルト９９）のベルト幅１１９はｗ＝６．４ｃｍ、拘束長１２５はｂ＝３０ｃｍ、帯状補強材１０１（ポリエステルベルト９９）の剛性ｋ＝１５３０００ｋｇｆ／ｃｍ^２である。
式４）から式６）を用いて最大値ｑ_ｍａｘ、最小値ｑ_ｍｉｎ、最大クラック幅ｄ_ｍａｘを算出すると、最大値ｑ_ｍａｘ＝１９２０ｋｇｆ、最小値ｑ_ｍｉｎ＝９６０ｋｇｆ、最大クラック幅ｄ_ｍａｘ＝０．１２ｃｍとなる。
従って、この補強を実施すると、最大クラック幅ｄ_ｍａｘ＝１．２ｍｍまでを拘束することができ、このときの帯状補強材１０１（ポリエステルベルト９９）１本あたりの張力１２１は、ｑ＝０．９ｔｆとなる。
第３０図は軸力と曲げとせん断を受ける柱１０５の概略図、第３１図は柱１０５に発生するクラック１１５を押し広げようとする力を示す図である。第２７図に示す方法で帯状補強材１０１としてポリエステルベルト９９を用いて補強された柱１０５に、軸力１２９（Ｐ）を加えつづけた状態で、水平力を加え、曲げモーメント１３１（Ｍ）、せん断力Ｑを繰り返し発生させた場合について、以下に補強効果を述べる。
柱１０５は、通常の構築部の柱を想定している。せん断力１２７（Ｑ）が柱１０５の高さｈの中間の高さ（ｈ／２）で水平に作用しており、柱１０５の上端と下端は回転しない様に水平にスライドするという条件である。この結果、柱１０５の内部には、水平方向に均等なせん断力（合力Ｑ）と軸力（合力Ｐ）が発生する。曲げモーメントは、上端部でＭ＝Ｑｈ／２、中間でゼロ、下端で−Ｍとなる。
せん断力１２７（Ｑ）が、柱１０５の鉄筋、コンクリートの状態から決まる最大せん断力Ｑ_ｍａｘに達すると、クラック１１５が角θ１３７の方向に発生する。このクラック１１５を水平方向に押し広げようとする力は、柱１０５に作用するせん断力１２７（Ｑ）である。この力を、矢印ｃ１３３で示す範囲の帯状補強材１０１で負担すると考える。帯状補強材１０１は、１本の幅がｗ、１本あたりの張力はｑなので、矢印ｃ１３３の範囲の帯状補強材１０１の合力Ｑは、Ｑ＝ｑ・２Ｃ／ｗである。
但し、柱１０５は長方形断面であるので、前面と背面がともに働くとして係数２を用いた。また、矢印ｃ１３３の長さＣは、第３１図から、Ｃ＝ｂｔａｎθである。一般には、せん断力Ｑは、部材内部でも負担しているが、ベルトが顕著な効果を発揮するＱ_ｍａｘ付近の変形を超えると、ほぼ全てのせん断力がベルトの張力によって負担されると仮定している。
今、角θ１３７＝４５度とすれば、柱１０５の幅１３５がｂ（拘束長）＝３０ｃｍである。よって、前に、式４）から式６）により算出した、ポリエステルベルト９９（幅６４ｍｍ、厚さ４ｍｍ）を使用したときの最大値ｑ_ｍａｘ、最小値ｑ_ｍｉｎに対応する水平力Ｑ_ｍａｘ、Ｑ_ｍｉｎは、Ｑ_ｍａｘ＝ｑ_ｍａｘ２ｂ／ｗ＝１８０００ｋｇｆ、Ｑ_ｍｉｎ＝ｑ_ｍｉｎ２ｂ／ｗ＝９０００ｋｇｆとなる。従って、本補強の効果で、クラック１１５の幅がｄ_ｍａｘ＝１．２ｍｍを越えない範囲では、９ｔｆ以上の水平抵抗力を保持することができる。
次に、補強なしの柱１０５と、第２７図に示す帯状補強材１０１として前述のポリエステルベルト９９（幅６４ｍｍ、厚さ４ｍｍ）を用いて補強した柱１０５について、第３０図に示す条件で、変位制御で水平繰り返し加力試験を実施した結果について述べる。但し、柱１０５のコンクリート強度は１３５ｋｇｆ／ｃｍ^２、軸方向鉄筋比０．５６％、せん断補強鉄筋比０．０８％、軸力は一定で、３７ｔｆ（軸力比０．３）である。
第３２図は、柱１０５の変形を示す概略図である。柱１０５の水平方向の変位を水平変位δ_ｈ１３９、鉛直方向の変位を鉛直変位δ_ｖ１４１とすると、実験により、第３３図から第３８図に示す結果が得られた。第３３図は柱１０５の水平力Ｑと変位履歴の包絡線を示す図である。第３４図は柱１０５の水平変位、鉛直変位、水平力の関係を示す図、第３５図は、柱１０５の復元力特性関係を示す図である。
第３３図の横軸は柱１０５の水平変位δｈ（１３９）を、縦軸は水平力Ｑ（せん断力１２７）を示す。第３５図の横軸は柱１０５の水平変位δｈ（１３９）と変形角を、縦軸は水平力Ｑ（せん断力１２７）を示す。
第３３図において、柱１０５を帯状補強材１０１で補強しない場合の包絡線が補強なし１４３ａ、補強した場合の包絡線が補強あり１４３ｂの曲線である。補強あり１４３ｂに示す包絡線は、第３５図に示す履歴ループ１５３の阪神大震災相当１５７ａ、阪神大震災２倍相当１５７ｂ、阪神大震災３倍相当１５７ｃ、阪神大震災５倍相当１５７ｄ等の点の包絡線である。
第３４図では、横軸が水平変位δ_ｈ（１３９）を、上向きの縦軸が水平力Ｑ（せん断力１２７）を、下向きの縦軸が鉛直変位δ_ｖ（１４１）を示す。補強なし１４３ａ、補強あり１４３ｂは、第３３図の補強なし１４３ａ、補強あり１４３ｂに示したのと同じ包絡線である。補強なし１４５ａは、帯状補強材で補強しなかった柱１０５の鉛直変位δ_ｖを、補強あり１４５ｂは、帯状補強材１０１（ポリエステルベルト９９）で補強した柱１０５の鉛直変位δ_ｖを示す曲線である。
第３３図、第３４図に示すように、補強なし１４３ａの場合の最大水平力をＱ_ｍａｘ１、補強あり１４３ｂの場合の最大水平力をＱ_ｍａｘ２、最小水平力をＱ_ｍｉｎとすると、実験のデータから、補強なし１４３ａの場合の最大水平力はＱ_ｍａｘ１＝１７．５ｔｆである。また、補強あり１４３ｂの場合の最大水平力はＱ_ｍａｘ２＝１８ｔｆ、最小水平力はＱ_ｍｉｎ＝７ｔｆである。
第３４図で、補強なしの柱１０５の水平力Ｑを示す補強なし１４３ａのライン、鉛直変位δ_ｖを示す補強なし１４５ａのラインは、水平力ＱがＱ_ｍａｘ１となった時点から急降下している。これは、補強した柱１０５では、Ｑ_ｍａｘ２に対応する水平変位から、Ｑ_ｍｉｎまでの水平変位の領域で、帯状補強材１０１（ポリエステルベルト９９）での補強効果によってせん断力の大半が負担されているという前記の仮定を裏付けている。
補強あり１４３ｂでの最小水平力Ｑ_ｍｉｎの実験データが、第３０図、第３１図のモデルを用いた計算値９ｔｆより小さいのは、実験誤差であるとともに、繰り返し荷重と変形で、柱１０５のコンクリート面と帯状補強材１０１（ポリエステルベルト９９）との接着面での強度低下が生じたことも考えられる。最大せん断力Ｑ_ｍａｘ２は、計算値１８ｔｆとほぼ等しい値である。
第３４図に示すように、柱１０５の水平変位δ_ｈが変位振幅δ_ｈｃ１４７のとき、水平力Ｑを示す補強あり１４３ｂの曲線には水平力変曲点１４９が、鉛直変位δ_ｖを示す補強あり１４５ｂの曲線には鉛直変位変曲点１５３がある。変位振幅δ_ｈｃ１４７は、第３５図に示す履歴ループ１５３の兵庫県南部地震３倍相当１５７ｃ付近の水平変位δ_ｈ、すなわち約１４０ｍｍ（変形角は０．１５ｒａｄ）である。
第３６図は、柱１０５の累積水平変位Σδ_ｈと履歴吸収エネルギＷの関係を示す図である。第３７図は第３６図の詳細図である。第３６図では、横軸が水平累積変位Σδ_ｈを、縦軸が履歴吸収エネルギＷを示す。
第３６図、第３７図の横軸に示す累積水平変位Σδ_ｈは、次の式で計算した。ここで、ｉは、データ記録のステップ数、ｎは現在のステップ数である。なお、累積水平変位Σδ_ｈは、第３５図に示す履歴ループ１５３上での位置を示す指標として計算している。

縦軸に示す履歴吸収エネルギＷは、次の式で計算した。履歴吸収エネルギＷは、水平力Ｑすなわちせん断力１２７のした仕事である。

構造物のある柱１０５が受け持つ軸力１２９がＰであれば、これに対応する質量ｍは、重力加速度ｇを用いて、ｍ＝Ｐ／ｇで表せる。従って、構造物に入力され、振動が終了するまでに消費されるエネルギのうち、柱１０５に作用するせん断力１２７がする仕事Ｅは、地震動の速度応答スペクトルＳｖを用いて、近似的に次の式で表される。

第３６図に示す履歴吸収エネルギ１５７の曲線は、第３５図に示す実験結果の履歴ループ１５３から式８）で計算した履歴吸収エネルギを表す。阪神大震災相当１５９ａおよび阪神大震災５倍相当１５９ｂの直線で示される値は、履歴吸収エネルギ１５７の曲線との比較のため、式９）で算出したものである。第３７図では、同様に式９）で算出した阪神大震災２倍相当１５９ｃ、阪神大震災３倍相当１５９ｄの値をさらに示している。式９を使用するにあたり、速度応答スペクトルは、固有周期０．３秒での神戸海洋気象台記録での値であるＳｖ＝９０ｃｍ／ｓを用いた。
第３８図は、式７）で算出した累積水平変位Σδ_ｈと鉛直変位δ_ｖの関係を示す図である。第３８図では、横軸が水平累積変位Σδ_ｈを、縦軸が鉛直変位δ_ｖ（１４１）を示す。第３４図の説明で述べたように、水平変位が変位振幅δ_ｈｃ１４７、すなわち約１４０ｍｍのとき、鉛直変位変曲点１５３があり、このとき、累積水平変位Σδ_ｈは約１５００ｍｍである。第３８図に示すように、鉛直変位変曲点１５３での累積変位約１５００ｍｍまでは、鉛直変位δ_ｖは５ｍｍ（歪０．５％）以下である。
この実験から、次のことが言える。
▲１▼従来の補強が困難である低強度コンクリート（１３５ｋｇｆ／ｃｍ^２）で補強効果を発揮した。
▲２▼歪の小さい範囲から大変形まで連続的に補強効果を発揮した。
▲３▼第３３図に示す補強あり１４３ｂの曲線で、水平力に２つの変曲点（Ｑ＝Ｑ_ｍａｘ２となる点、およびＱ＝Ｑ_ｍｉｎとなる点、すなわち水平力変曲点１４９）が確認された。
▲４▼第３４図に示す補強あり１４５ｂの曲線で、鉛直変位δ_ｖにひとつの変曲点（鉛直変位変曲点１５３）が確認された。これは、▲３▼に記述した水平力変曲点１４９（Ｑ＝Ｑ_ｍｉｎ）に対応する点である。なお、鉛直変位変曲点１５３は、繰り返し荷重によってコンクリートが累積損傷し、コンクリート強度が低下し、帯状補強材１０１（ポリエステルベルト９９）と柱１０５のコンクリート面の接着強度τが低下し、クラック幅１１７が限界ｄ_ｍａｘを越え、式１から式６）のメカニズムが成り立たなくなった結果、柱１０５の断面形状が変化を開始し、大きな軸変形を生じるメカニズムに移行した点である。
▲５▼水平力Ｑの第２変曲点、すなわちＱ＝Ｑ_ｍｉｎとなる水平変曲点１４９に達するまで、即ち鉛直変位δ_ｖが鉛直変位変曲点１５３に達するまでは、鉛直変位δ_ｖ（柱１０５の軸縮み）は０．５％以下であり、実用上、構造物が地震後再利用できる許容範囲である。
▲６▼補強しない場合（第３３図、第３４図に示した補強なし１４３ａ、１４５ａの場合）には、阪神大震災相当の履歴吸収エネルギ以前に鉛直変位δ_ｖが急拡大し、構造物は崩壊したと考えられる。
▲７▼補強した場合、第３６図、第３７図に示す履歴吸収エネルギ１５７が阪神大震災約２．５倍相当の履歴吸収エネルギとなるまでは鉛直変位δ_ｖが０．５％以下であり、実用上、構造物が地震後再利用できる許容範囲である。
▲８▼補強した場合には、第３８図に示すように、阪神大震災約２．５倍相当の履歴吸収エネルギ（累積水平変位Σδ_ｈが約１５００ｍｍ）を越えると、鉛直変位δ_ｖは徐々に拡大する。しかし、第３４図、第３５図に示すように、水平耐力が上昇し、１サイクルあたりの吸収エネルギが増えるので、制振効果が高まり、大きな崩壊防止効果がある。
第８の実施の形態により、柱１０５等の部材にポリエステルベルト９９等の帯状補強材１０１を直接接着する方法は、第３３図から第３８図の実験結果に示されるように、クラック１１５の発生後の小さな変形から大きな変形まで、連続的に補強効果を発揮する。
従来、部材を巻き立てて補強する場合は、クラックの発生を防ぐべく、部材を構成する主要な力学的要素の剛性と同等以上の剛性を持った炭素繊維、巻き鉄板等の補強材料を部材表面に直接樹脂等で張り付けることを特徴としていたが、第８の実施の形態では、部材表面のクラック１１５の発生を抑止しようとするのではなく、クラック幅１１７を有効な値、例えば２ｍｍ程度に押さえることで、部材の機能低下を制御し、構造物の使用性や安全性を維持する。
ポリエステルベルト９９等の剛性が大きな材料を用いて部材表面に直接接着する方法は、有限なクラック１１５を伴う変形の範囲で、部材の形状を保持する効果を高めることを狙っている。この効果は、式１から式４）に示したように、補強材周方向の剛性に比例して高くなり、部材表面と補強材の間で伝達されるせん断力の大きさによって限界がある。よって、部材と、剛性の大きな補強材を直接接着することによって、効果を高めることができる。
なお、第８の実施の形態で使用する帯状補強材１０１は、ポリエステルベルト９９に限らない。同等の強度、剛性を持つ任意の材質を使用することができる。
また、第８の実施の形態の補強方法は、クラック幅１１７の増大を制御することによって、部材の見かけの体積の膨張を抑える方法であり、原理的には前出願に等しいが、形状変化と軸歪を抑えるメカニズムを考案し、理論式と実験で実証したことは、今後の実用上意義が大きい。
次に、第９の実施の形態について説明する。第９の実施の形態は、第１の実施の形態と同様に、凹凸のある部材、ならびに部材と部材の接合部の補強効果を高める方法である。第３９図は、柱１６１と梁１６３の接合部に接続用補強材１６９ａ、１６９ｂを設置した状態を示す斜視図である。柱１６１の左右の側面１６５ｂには、梁１６３が接合されている。
柱１６１と梁１６３の接合部は、まず、２枚のシート状の接続用補強材１６９ａと、４枚の接続用補強材１６９ｂとで補強される。接続用補強材１６９ａは、シート状の補強材であり、柱１６１の側面１６５ｂと梁１６３の側面１６７ａとの接合部を覆うように接着される。接続用補強材１６９ａの中央部は、柱１６１の側面１６５ａと左右に隣接する側面１６５ｂとに接着され、両端部は、梁１６３の側面１６７ａに接着される。
接続用補強材１６９ｂはシート状の補強材であり、柱１６１の側面１６５ｂと梁１６３の側面１６７ｂとの接合部を覆うように接着される。接続用補強材１６９ａ、１６９ｂは、例えば、繊維系、ゴム系等の伸展性のあるシート材である。
接続用補強材１６９ａ、１６９ｂは、シート状の補強材ではなく、ポリエステルベルト９９等の帯状補強材を用いても良い。シート材、帯状補強材のいずれを用いる場合でも、接続用補強材１６９ａ、１６９ｂの厚さ、幅、長さ等は、必要な補強量に相当する寸法とする。
接続用補強材１６９ａ、１６９ｂを柱１６１や梁１６３に接着する方法は、第１の実施の形態の補強材７ａ等と同じく仮付けでもよいが、第７の実施の形態の補強材８５のように、強度を期待した接着を用いることができる。一般に、構造物の変位振幅は、部材と部材の接合部の変形に大きく左右されるので、後述の第４３図のステップ２０９に示した方法で補強量が決定されることを考えると、後者を用いることが実用的である。
第４０図は、柱１６１と梁１６３の接合部に帯状補強材１７１ａ、１７１ｂを設置した状態を示す斜視図である。第４０図では、第３９図に示すように設置された接続用補強材１６９ａ、１６９ｂを覆うように、１本の帯状補強材１７１ａと、２本の帯状補強材１７１ｂが設置される。帯状補強材１７１ａは、太い側の部材、すなわち柱１６１の周囲に設置される。帯状補強材１７１ａは、斜めに柱１６１と梁１６３の接合部を跨ぎ、接合部の上方と下方とで連続して巻き付けられる。帯状補強材１７１ｂは、細い側の部材、すなわち梁１６３の周囲に設置される。帯状補強材１７１ｂは、柱１６１の左右に接合された梁１６３にそれぞれ独立して巻き付けられる。
この方法を繰り返し用いて補強量を必要な量まで増やす。第４０図では帯状補強材１７１ａ、１７１ｂを二重に設置し、柱１６１と梁１６３の接合部で襷がけにしてある。
柱１６１、梁１６３への帯状補強材１７１ａ、１７１ｂの接着には、前出願および本出願で用いたように強度を期待した接着を用いる。第４１図は、接続用補強材１６９ｂ等が設置された柱１６１と梁１６３の接合部の断面図を示す図である。シート状の接続用補強材１６９ｂの上には、帯状補強材１７１ａ、１７１ｂが巻き付けられる。柱１６１や梁１６３とシート状の接続用補強材１６９ｂ、接続用補強材１６９ｂと帯状補強材１７１ａ、１７１ｂは、お互いの張力を接着面のせん断抵抗を介して伝達するように接着される。柱１６１や梁１６３と接続用補強材１６９ａ、接続用補強材１６９ａと帯状補強材１７１ａ、１７１ｂも同様に接着される。
なお、必要に応じて、柱１６１の周囲に補強材１７３ａを、また、梁１６３の周囲に補強材１７３ｂを巻き付ける。補強材１７３ａ、１７３ｂは、伸展性のあるシート材や帯状材である。
このように、第９の実施の形態では、柱１６１と梁１６３との接合部に接続用補強材１６９ａ、１６９ｂを設けて、部材間の補強効果を高める。さらに、帯状補強材１７１ａを太い方の部材である柱１６１に襷がけにし、接合部を跨いで巻きつけたり、帯状補強材１７１ａ、１７１ｂを柱１６１や梁１６３の周囲に多重に巻きつけることで、必要な補強量を確保する。
第３９図、第４０図では、十字型の接合部を示したが、Ｔ型等の接合部でも同様の方法で施工できる。さらに、柱と梁の組合せに限らず、他の部材同士の接合部の補強にも有効である。また、第１、第２の実施の形態に示すような、スリットや孔を用いる方法と併用することもできる。これは、スラブと梁、壁と梁など、厚さや形状の大きく異なる部材間の接合部の補強に対して、特に有効である。なお、帯状補強材１７１ａ、１７１ｂのみで十分な補強量を得られる場合には、接続用補強材１６９ａ、１６９ｂを省略してもよい。
第４２図、第４３図は、本発明の方法で部材の補強を行うときの補強量の設計のフローチャートを示す図である。第４２図、第４３図のフローチャートを用いて、補強諸元を決定する方法について説明する。
第４２図に示すように、まず、構造物の重量、形状、機能等の限界条件を決定する（ステップ２０１）。同時に、構造物に作用する突発的外力の振幅、周期、継続時間、エネルギを決定する（ステップ２０２）。さらに、構造物に作用する突発的外力の内、鉄筋、コンクリート等、従来の材料で負担する部分を決定する（ステップ２０３）。
次に、構造物や部材を新設する場合など、部材諸元を決定する場合（ａ）には、ステップ２０１からステップ２０３での決定事項を考慮して部材諸元を決定する（ステップ２０４）。部材諸元は、通常の構造設計計算方法もしくは他の補強指針を用いて決定することができる。
次に、本方法で負担する自重等の常時の荷重と突発外力を決定する（ステップ２０５）。すなわち、本発明の方法、構造、材料で負担する突発的な外力の種類、性質と大きさ（振幅、周期、継続時間、エネルギ）を決定する。これは、ステップ２０１で決定した、構造物がその耐用期間に受けると考えられる突発的外力のエネルギから、本発明の方法での補強以外で耐えうる突発的外力のエネルギ（ステップ２０３で決定した、従来の材料で負担する部分など）を除いたものとすることもできる。従って、新設時点の構造設計で本発明の補強を用いることを考慮する場合には、部材の材料、部材諸元を、この補強を考慮して節約することができる。
なお、既存の構造物や部材を補強材で補強する場合など、部材諸元を決定しない場合（ｂ）には、ステップ２０２、ステップ２０３での決定事項からステップ２０５の内容を決定する。この場合も、構造物がその耐用期間に受けると考えられる突発的外力から、本発明の方法での補強以外で耐えうる突発的外力を除いたものとして決定することができる。
次に、部材に作用する断面力の振幅とエネルギを計算する（ステップ２０６）。すなわち、ステップ２０２で決定した、突発的な外力の種類、性質と大きさから、補強した部材、その他の部材を含む部材に作用する断面力（せん断力、軸力、曲げモーメント等）および部材の変形（せん断歪、軸歪、曲げ歪等）の振幅と大きさを計算する。同時に、構造物全体の突発外力による変位振幅と振動エネルギを計算する（ステップ２０７）。
ステップ２０６、ステップ２０７について、厳密には、第３５図に示したような補強した部材とその他の部材の復元力特性を考慮した有限要素法、フレーム解析法等の構造解析計算を行うことによって計算できる。簡略法としては、通常の構造設計で行われているように、構造系を単純化して、エネルギー定則などの仮定を設けて行うことができる。従来の計算と比較して対象とする変形範囲が広いことを除けば、復元力特性が明らかな部材の構造設計と同じ要領で行うことができる。
次に、補強した部材の補強量と復元力特性、軸歪の関係を決定する（ステップ２０８）。ステップ２０６、ステップ２０７の計算により、ステップ２０８の内容を決定する。このとき、一般には、第４３図の破線で示したように、ステップ２１０からステップ２０８を介してステップ２０６及びステップ２０７の間のフィードバックが必要になる。
そして、構造物の地震等の突発的な外力作用後の機能・使用性・修復可能性等の限界条件を決定し（ステップ２０９）、これとステップ２０７で計算した構造物の変位振幅と振動エネルギを比較して、補強諸元を決定する（ステップ２１０）。
すなわち、ステップ２０６からステップ２０８で計算した構造物の変形と、ステップ２０９で決定した、地震等の突発外力が作用した後にどのような形で構造物を使用するかの条件から求まる許容変形量とを比較し、補強諸元を決定する。この際、ステップ２０１で決定した構造物の重量、形状、機能等の限界条件も考慮に入れる。
大地震等に関しては、ステップ２０９で、崩壊しなければよいという条件であれば、許容変形は大きくとることができる。一方、新幹線の高架橋等のように、大地震直後であっても変形が大きいと脱線等の危険がある場合には、これを考慮して補強量を決定する。
第１から第９の発明は、伸展性のある材料を部材表面に接着剤で設置して、見かけの体積の膨張を拘束することによって、部材の破壊を制御する方法（前出願）の効果を高める補強方法、補強構造、免震装置に関するものである。
前出願では、補強材料として、ポリエステルシートなどの、安価で加工や接着が容易な材料を用いている。これらの補強材料のヤング率は、コンクリートの１０分の１、鉄の１００分の１程度である。よって、鉄筋コンクリートの鉄筋のような形で、歪が極めて小さい弾性範囲内で部材に作用する荷重の一部を直接分担する効果は、上記のヤング率の比に比例して、ごく小さい。
しかし、繰り返し荷重の作用により、部材を主として構成する鉄やコンクリート等の材料が降伏したり、ひび割れを発生したりして、塑性変形を開始した以降には、部材の剛性が低下するので、前出願の方法は、顕著な効果を発揮する。すなわち、部材を構成するコンクリート等の材料が粒状体を経て粉体となり、鉄が大きく塑性変形したり破断した以降も、これらを一体化させて保持し、軸力保持能力、曲げやせん断などの外力への抵抗能力を発揮させることができる。
補強した部材は、剛性を保持しながら、上述の一連の繰り返し変形過程で極めて大きなエネルギを吸収するので、地震等の突発的な外力から、構造物の崩壊を防止することができる。鉄筋コンクリート柱の例については、第８の実施の形態の部分で実験結果を示した。
第４４図は、繰り返し荷重の作用による、補強した部材の累積変形と履歴吸収エネルギの関係を示す図である。横軸は累積変形を、縦軸は履歴吸収エネルギを示す。部材が、有限なひび割れを伴って変形する間にも、繰り返し外力の作用を受けることによって、部材を構成する材料が部分的な破壊を生ずる。従って、部材と補強材の間で伝達されるせん断力はこれに応じて低下するので、補強効果も低減し、部材の形状を保持する効果も低減する。繰り返し荷重による部材を構成する材料の破壊は、外力のした仕事、すなわち履歴吸収エネルギで計ることができる。
材料の種類と量に応じて、ある限界（形状保持限界エネルギ１６１と称する）が存在し、これを超えると材料が粒状体的に振る舞うので、部材の形状が顕著に変化し始める。本発明、ならびに前出願の方法で補強した部材では、断面は円形に、全体形状は球を繋げた形に近づいていく。これによって、構造物の形状も顕著に変化する。
第６の実施の形態の第１８図から第２０図に示した免震装置５５、５５ａ、５５ｂの例は、この形状を先取りすることで、形状保持限界エネルギ１６１以降の形状変化を最小に抑えて、構造物の地震後の使用性を確保しうる履歴吸収エネルギ領域、すなわち入力地震動のエネルギ領域を増やすことを狙っている。この形状の工夫も前出願の効果を高める方法の一つである。
また、形状保持限界エネルギ１６１以前の過程で、部材内部には、部材を構成するコンクリートなどの材料を破壊する摩擦力と熱が発生する。第６の実施の形態の第２０図についての説明で述べたように、特殊な充填材をコンクリート６７等の前記の材料に混入させることで、上記の熱や摩擦力で充填材の内容物が染み出して材料の強度低下を抑え、形状保持エネルギ１６１を高めることができる。
第４４図に示すように、広い範囲のエネルギ領域と変形領域に対応できることが、前出願の特徴であり、本発明の方法は、この効果を高める方法である。さらに、免震装置に前出願と本発明の方法を用いた場合には、形状変化を最小に抑え、剛性を保持しつつ、装置の体積に相当する材料がほぼ完全に粉砕されるエネルギ量を吸収することができる。これは、免震装置としては極めて効率的な方法である。さらに、特殊な充填材を混入し、上記の過程の外力仕事によって発生する熱などのエネルギを利用して材料を内部で補強することで、免震効果を一層高めることができる。
次に、第１０の実施の形態について説明する。第１０の実施の形態では、第１から第９の実施の形態で用いられる繊維系のシート状補強材や帯状補強材に、樹脂を含浸させる。第４５図は、樹脂を含浸させた補強材料および含浸させない補強材料の引張応力歪関係を示す図である。縦軸は張力を、横軸は伸び歪（％）を表す。
樹脂を含浸させた場合１７５の曲線は、ポリエステル製のシート状織布にエポキシ樹脂を含浸させ、樹脂が硬化した後に引張試験を行った応力歪関係を示す。含浸させない場合１７７の曲線は、同じシート状織布にエポキシ樹脂を含浸させずに引張試験を行った応力歪関係を示す。
第４５図で、樹脂を含浸させた場合１７５と含浸させない場合１７７の曲線を比較すると、樹脂を含浸させることによって、歪０％から約３％までの範囲で剛性、即ちグラフの割線勾配が顕著に大きくなっていること、かつ、歪の大きい範囲まで破断することなく変形できることが読み取れる。なお、第２４図に示すポリエステルベルト９９等のポリエステル製の帯状材料でも、同様の試験結果が得られる。
第４５図に示す試験結果は、樹脂を含浸させた場合１７５には、ポリエステル繊維で織ったシートもしくは帯状の材料に樹脂を含浸させたことによって、歪の小さい範囲内では樹脂が繊維の変形を拘束する効果があり、含浸させない場合１７７に比べて剛性が増加することを示している。また、変形が大きくなると、樹脂を含浸させた場合１７５では、繊維を大きく破損しないで前記の効果が失われる結果、１５％以上の大きな歪まで変形性能を保ち得ることを示している。
このように、樹脂を含浸させた補強材料を第１から第９の実施の形態で用いたシート状補強材、もしくは帯状補強材として用いることによって、単一種類の材料で、歪の小さい範囲で変形を抑制する効果を高めながら、なおかつ、歪の大きい範囲での荷重保持効果を得ることができる。第１０の実施の形態の補強材料は、第７の実施の形態の補強材８５と補強材８７を単一種類の材料で可能にする方法である。
産業用の利用可能性
このように、本発明にかかる構造物の補強構造、免震装置および補強方法は、補強する部材に起伏や凹凸のある場合、他の部材や非構造部材と接合されているか、極めて近接している場合、部材と補強材、補強材と外界の作用によって補強材が劣化する可能性のある場合、小さい範囲の変形から大きな変形まで補強効果を必要とする場合、免震補強が必要な場合等に用いるのに適している。
【図面の簡単な説明】
第１図は、補強される部材の斜視図である。
第２図は、補強後の第１図のＡ−Ａ断面図である。
第３図は、補強後の第１図のＡ−Ａ断面図である。
第４図は、補強される部材の斜視図である。
第５図は、接続用補強材１５の平面図である。
第６図は、補強後の第４図のＢ−Ｂ断面図である。
第７図は、補強後の第４図のＢ−Ｂ断面の一部を示す図である。
第８図は、補強される扁平部材３１の斜視図である。
第９図は、接続用補強材３５の斜視図である。
第１０図は、補強後の扁平部材３１の孔３３付近の断面図である。
第１１図は、補強後のＨ型部材４３の斜視図である。
第１２図は、補強後の中空部材４９の斜視図である。
第１３図は、免震装置５５の斜視図である。
第１４図は、免震装置５５、５５ａ、５５ｂのいずれかを使用した構造物５３の立面図である。
第１５図は、免震装置５５、５５ａ、５５ｂのいずれかを使用した構造物５３の立面図である。
第１６図は、免震装置５５、５５ａ、５５ｂのいずれかを使用した構造物５３の立面図である。
第１７図は、第１４図から第１６図に示すように構造物の層に設置された免震装置５５ｂ付近の鉛直断面図である。
第１８図は、第１４図から第１６図に示すように構造物の層に設置された免震装置５５ａ付近の鉛直断面図である。
第１９図は、免震装置５５ａの水平断面図である。
第２０図は、コンクリート製の免震装置５５ｂの水平断面図である。
第２１図は、第１４図から第１６図に示す層５７、５７ａ、５７ｂの鉛直部材６９に作用する力を示す図である。
第２２図は、補強後の部材８１の断面の一部を示す図である。
第２３図は、部材８１の荷重変形関係を示すグラフである。
第２４図は、ポリエステルベルト９９の平面図である。
第２５図は、帯状補強材１０１で補強した柱１０５の例を示す斜視図である。
第２６図は、帯状補強材１０１で補強した柱１０５の例を示す斜視図である。
第２７図は、第２６図に示す柱１０５の立面図である。
第２８図は、第２５図から第２７図に示す柱１０５の表面付近の断面図である。
第２９図は、帯状補強材１０１とクラック１１５の有効接着長の関係を示す図である。
第３０図は、軸力と曲げとせん断を受ける柱１０５の概略図である。
第３１図は、柱１０５に発生するクラック１１５を押し広げようとする力を示す図である。
第３２図は、柱１０５の変形を示す図である。
第３３図は、柱１０５の水平力Ｑと変位履歴の包絡線を示す図である。
第３４図は、柱１０５の水平変位、鉛直変位、水平力の関係を示す図である。
第３５図は、柱１０５の復元力特性関係を示す図である。
第３６図は、柱１０５の累積水平変位Σδ_ｈと履歴吸収エネルギＷの関係を示す図である。
第３７図は、第３６図の詳細図である。
第３８図は、累積水平変位Σδ_ｈと鉛直変位δ_ｖの関係を示す図である。
第３９図は、柱１６１と梁１６３の接合部に接続用補強材１６９ａ、１６９ｂを設置した状態を示す斜視図である。
第４０図は、柱１６１と梁１６３の接合部に帯状補強材１７１ａ、１７１ｂを設置した状態を示す斜視図である。
第４１図は、接続用補強材１６９ｂ等が設置された柱１６１と梁１６３の接合部の断面図を示す図である。
第４２図は、補強量の設計のフローチャートを示す図である。
第４３図は、補強量の設計のフローチャートを示す図である。
第４４図は、補強した部材の累積変形と履歴吸収エネルギの関係を示す図である。
第４５図は、樹脂を含浸させた補強材料および含浸させない補強材料の引張応力歪関係を示す図である。
符号の説明
１，２１ 角型部材
３，２３ 扁平部材
５ スリット
７ａ，７ｂ，７ｃ，１３ａ，１３ｂ，２７，２９，４１，４５，８５，８７，１７３ａ，１７３ｂ 補強材
９，１１ 接着剤
１５，３５ 接続用補強材
１７，３７，１６９ａ，１６９ｂ 接着面
１９，３９ 連結部
２５，３３ 孔
４７ 充填材
５３ 構造物
５５ 免震装置
５７，５７ａ，５７ｂ 層
５９ 基礎
８１ 部材
８３，８９ 保護用補強材
９９ ポリエステルベルト
１０１，１７１ａ，１７１ｂ 帯状補強材
１０５，１６１ 柱
１１７ クラック幅
１２１ 張力
１６３ 梁Technical field
The present invention relates to a reinforcing structure for a structure, a reinforcing material, a seismic isolation device, and a reinforcing method.
Background art
Conventionally, there is a method (PCT / JP00 / 09283, hereinafter referred to as a prior application) for controlling the breakage of a member by installing an extensible material on the outer peripheral portion of the member and maintaining and improving the load bearing capacity after the breakage.
However, if the shape of the member is uneven or uneven like a walled pillar, the reinforcing member is joined to another member or a non-structural member like a pillar in which a window frame or the like is installed, In the case of extremely close proximity, a sufficient reinforcing effect cannot be obtained. Further, there is a possibility that the reinforcing material may be deteriorated by the action of the member and the reinforcing material, and the reinforcing material and the outside world. Furthermore, there is a case where a reinforcing effect is required from a small range of deformation to a large deformation, or seismic isolation reinforcement is necessary.
This invention is made | formed in view of such a problem, The place made into the objective is to provide the reinforcement structure of the structure which can improve a reinforcement effect, a seismic isolation apparatus, and the reinforcement method.
Disclosure of the invention
1st invention is the reinforcement method of the structure which installs a reinforcing material in the outer peripheral surface of a several adjacent member, Comprising: The space which penetrates between the 1st member which adjoined or was joined, and another member A reinforcing method for a structure is characterized in that a reinforcing material is passed through.
The first member is, for example, a prism, and the other member is a wall that is close to or joined to the side surface of the prism. 1st invention is the method of reinforcing the member which has undulations and unevenness | corrugations. The space is, for example, a gap between adjacent prisms and walls, or a slit or hole provided at a joined part between the joined prisms and walls. As the reinforcing material, for example, a rubber-based or fiber-based sheet material or a belt-shaped material is used. By passing the reinforcing material through the space and installing the reinforcing material so as to go around the outer periphery of the prism, tension is transmitted in the circumferential direction of the first member.
In 1st invention, in the reinforcement method which installs a reinforcing material in the outer peripheral surface of a several adjacent member, it reinforces to the space which penetrates the space | interval between several adjacent members, and the junction part of several joined members. Pass the material.
A second invention is a method for reinforcing a structure in which a reinforcing material is installed on the outer peripheral surface of a flat member, and a band-shaped reinforcing material having adhesive surfaces at both ends is passed through a space penetrating the flat member. This is a method for reinforcing a structure.
The flat member is, for example, a wall. A space is a hole or the like provided in a flat member. As the reinforcing material, for example, a band material such as rubber or fiber is used. At both ends of the belt-like material, a bonding surface is provided, for example, in a trumpet shape as necessary to ensure a bonding area. By passing the reinforcing material through the space, the tension is transmitted between the facing side surfaces of the flat member.
In 2nd invention, in the reinforcement method of the structure which installs a reinforcing material in the outer peripheral surface of a flat member, a reinforcing material is passed through the space provided so that the flat member might be penetrated.
According to a third aspect of the present invention, there is provided a method for reinforcing a structure in which a sheet-like reinforcing material is formed in a cylindrical shape on the outside of a member, and a granular filler is filled inside the reinforcing material.
The member is a hollow member or a member having a complicated cross-sectional shape. As the reinforcing material, for example, a fiber material, a rubber material, a metal sheet or the like is used. As the filler, for example, a natural granule such as sand or an artificial granule such as resin is used. When the member is about to deform with apparent volume expansion, the particulate filler transmits this to the reinforcement to control the deformation. In addition to this, an inorganic material can also be used as the filler in order to obtain an effect of protecting the member from heat and the like.
In 3rd invention, a reinforcing material is formed in a cylinder shape along the outer periphery of a member, and the filler of a granular material is filled into the inside of a member. Alternatively, a space is provided between the reinforcing member and the reinforcing member is formed in a cylindrical shape, and a granular filler is filled between the reinforcing member and the member.
A fourth invention is a seismic isolation device, wherein a reinforcing material is provided around a granular filler, a concrete member, or a steel member.
As the reinforcing material, for example, a fiber material, a rubber material, a metal sheet material, or a band material is used. As the filler, for example, a natural granule such as sand or an artificial granule such as resin is used. Inside the filler, the concrete member, and the steel member, a material that resists tension, such as a reinforcing bar, is disposed as necessary. Moreover, the filler which prevents a strength fall may be mixed in the inside of concrete. The horizontal cross section of the seismic isolation device of the fourth invention is preferably circular.
In the fourth aspect of the invention, the reinforcing material is installed around the granular filler, the concrete member, or the steel member.
A fifth aspect of the invention is a method for reinforcing a structure, characterized in that the seismic isolation device of the fourth aspect of the invention is installed in a layer of a structure, between a foundation of a structure and a frame, or on the foundation of a structure. is there.
When installing in a layer of a structure, install a seismic isolation device as a pillar. Or it installs between the foundation of a structure, and a frame, ie, a superstructure. When installing on the foundation of a structure, install it with a normal pile. The seismic isolation device according to the fourth aspect of the present invention exhibits a seismic isolation effect against vibrations in the three-dimensional directions that are up, down, left, and right of the structure.
In 5th invention, the seismic isolation apparatus of 4th invention is installed in the layer of a structure as a pillar. Or install it as a seismic isolation device between the foundation of the structure and the frame. Sometimes installed as a pile and seismic isolation device on the foundation of the structure.
6th invention is the reinforcement method of the structure which installs a reinforcing material in the outer peripheral surface of a member, Comprising: A plurality of reinforcing materials are installed in multiple in the outer peripheral surface of the said member, The reinforcement of the structure characterized by the above-mentioned Is the method.
The plurality of reinforcing materials are, for example, a plurality of reinforcing materials made of materials having different Young's moduli, a plurality of reinforcing materials that reinforce members with different mechanical mechanisms, and the like. These can be realized by changing the material, thickness, width, installation amount and the like of the reinforcing material. You may install further the protective reinforcement for protecting these reinforcements from the effect | action of a member or the external environment.
In 6th invention, the several reinforcing material which has a different characteristic is multiply installed in the outer peripheral surface of the said member.
7th invention adheres a strip | belt-shaped reinforcement to the outer periphery of a member with an adhesive agent, suppresses the increase in the crack width of the said member with the said strip | belt-shaped reinforcement, and controls destruction. This is a reinforcing method.
As the reinforcing material, a belt-like material made of a material having higher rigidity and strength than the polyester sheet, for example, a fiber material such as polyester is used. The band-shaped reinforcing material is wound around the member in a spiral shape without any gaps. Or you may install the reinforcing material which circulates a member in a multistage | stage at predetermined intervals. Alternatively, it may be installed without a gap in the axial direction of the member or at a predetermined interval. The reinforcing material having high rigidity and strength directly bonded to the surface of the member with an adhesive exhibits a reinforcing effect continuously from a small range to a large range of deformation of the member.
In the seventh invention, a band-shaped reinforcing material is directly bonded to the outer periphery of the member with an adhesive, and an increase in the width of cracks generated in the member due to the tension of the reinforcing material is suppressed.
An eighth invention is a method for reinforcing a structure that reinforces a joint portion of a plurality of members, wherein an end portion of a sheet-like or strip-like reinforcing material is bonded to a side surface of the first member, and is continuous with the end portion. A structure reinforcing method is characterized in that a portion to be bonded is adhered to a side surface of a second member, and the joint portion between the first member and the second member is covered with the reinforcing material.
The first member and the second member are, for example, a beam and a column. The thickness, width, length and other dimensions of the sheet-like or belt-like reinforcing material are determined in consideration of the load acting on the joint. The end portion of the reinforcing material is bonded to the side surface of the beam, the portion following the end portion is bonded to the side surface of the column, and the joint between the column and the beam is covered with the reinforcing material. When another beam is joined to the other side surface of the column as the third member, the other end of the reinforcing material may be bonded to the side surface of the other beam.
In the eighth invention, one end of the sheet-like or belt-like reinforcing material is bonded to the side surface of the first member, the other end is bonded to the side surface of the second member, and the joint portion is covered with the reinforcing material.
A ninth aspect of the invention is a reinforcing method for reinforcing a member having a joint portion, wherein a strip-shaped reinforcing material is spirally wound around the member above and below the joint portion. A method for reinforcing a structure, characterized in that a band-shaped reinforcing material is wound and wound.
The joining portion is, for example, a joining portion between the first member and the second member of the eighth invention. The strip-shaped reinforcing material of the ninth invention may be wound around the reinforcing material of the eighth invention. In this case, the belt-like reinforcing material and the reinforcing material of the eighth invention are bonded so as to transmit each other's tension. Or it can also be set as the structure which reinforces a member independently, without mutually bonding according to the performance requirement of the junction part reinforced. Moreover, a strip | belt-shaped reinforcement material may be repeatedly wound in multiple times.
In 9th invention, a strip | belt-shaped reinforcement is continuously wound around the whole surface of the member containing a junction part. The wire is wound spirally above the joint, wound around the joint, and wound spirally below the joint.
A tenth invention is a reinforcing material characterized in that a fiber-based material having impregnation property is impregnated with a resin.
In the tenth aspect of the invention, by impregnating a resin in a sheet-like or strip-like fiber material that is extensible and impregnated, the rigidity in a small strain range is increased, and the strain in a large strain range is increased. Maintains deformation performance. The reinforcing material of the tenth invention is used for the structure reinforcing method and seismic isolation device of the first to ninth inventions.
An eleventh invention is a reinforcing structure for a structure reinforced by the method for reinforcing a structure according to any one of the first to third and fifth to ninth inventions.
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a perspective view of a member to be reinforced. The member to be reinforced is a member in which the flat member 3 is joined to both ends of the square member 1. For example, the square member 1 is a column and the flat member 3 is a walled column or the like. In the vicinity of the joint between the square member 1 and the flat member 3, a slit 5 that penetrates the flat member 3 is provided in order to deal with surface irregularities formed between the square member 1 and the flat member 3.
2 and 3 show the AA cross-sectional view of FIG. 1 after reinforcement. First, the reinforcement shown in FIG. 2 will be described. In FIG. 2, the square member 1 is reinforced by using sheet-like reinforcing materials 7 a, 7 b, 7 c, an adhesive 9, and an adhesive 11 having a length of about three quarters of the circumference of the square member 1. Is done.
The reinforcing material 7a is installed from the side surface 8a side through the slits 5 at both ends, and covers the surface of about three-quarters of the circumferential length of the square member 1. Both ends of the reinforcing material 7 a are temporarily attached to the square member 1 with an adhesive 11. The reinforcing material 7b is installed through the slit 5 at both ends from the side surface 8b. The reinforcing material 7b covers the remaining surface of the square member 1, that is, the side surface 8b, and both ends are placed on the outside of the reinforcing material 7a. Both ends of the reinforcing material 7 b are bonded to the reinforcing material 7 a with an adhesive 9.
The reinforcing material 7c is installed through the slit 5 at both ends from the side surface 8a so as to overlap the reinforcing material 7a. Both ends of the reinforcing material 7c are placed on the outside of the reinforcing material 7b and are bonded to the reinforcing material 7b with an adhesive 9.
Next, the reinforcement shown in FIG. 3 will be described. In FIG. 3, the square member 1 is a sheet-like reinforcing material 13 a having a length of slightly less than about 1 times the circumferential length of the square member 1, and a length of about 1 times the circumferential length of the square member 1. It is reinforced using a sheet-like reinforcing material 13b, adhesive 9, and adhesive 11.
The reinforcing member 13a is wound around substantially the entire surface of the square member 1 through the slit 5 so that one end is at the corner of the side surface 14b and the other end is at the surface of the side surface 14b. One end of the reinforcing material 13a is temporarily attached to the surface of the side surface 14b using the adhesive 11.
The reinforcing member 13b is wound around the outside of the reinforcing member 13a in a cylindrical shape through the slit 5 so that both ends are on the side surface 14a side of the square member 1. The reinforcing material 13 b is bonded to the reinforcing material 13 a by using the adhesive 9 at a position overlapping the adhesive 11. One end of the reinforcing member 13b is bonded to the vicinity of the other end of the reinforcing member 13b using the adhesive 9.
Reinforcing materials 7a, 7b and 7c shown in FIG. 2 and reinforcing materials 13a and 13b shown in FIG. 3 are, for example, fiber-based, rubber-based, and other extensible sheet materials. The adhesive 11 temporarily attaches the reinforcing materials 7a and 13a to the square member 1 and is devised so as not to be excessively bonded. The adhesive 9 is made of a material that allows the reinforcing members 7a, 7b, and 7c and the reinforcing members 13a and 13b to sufficiently transmit tension to each other.
As described above, in the first embodiment, the slit 5 is provided in the joint portion between the adjacent square member 1 and the flat member 3 and the reinforcing material is passed through to transmit the tension in the circumferential direction of the square member 1. And enhance the reinforcement effect. In FIG. 1, the slits 5 are provided in the vicinity of the joints of the plurality of joined members. However, it is also possible to install a reinforcing material by assuming that the gaps between the adjacent members correspond to the slits 5. Moreover, the reinforcing method of 1st Embodiment can be used not only for the junction part of the square member 1 and the flat member 3, or an adjacent part, but for the member of arbitrary shapes with ups and downs, an unevenness | corrugation.
Next, a second embodiment will be described. FIG. 4 shows a perspective view of a member to be reinforced. In the second embodiment, the same members as those in the first embodiment are reinforced by different methods. In the vicinity of the joint portion between the square member 21 corresponding to the square member 1 of the first embodiment and the flat member 23 corresponding to the flat member 3, a plurality of holes 25 penetrating the flat member 23 are provided at predetermined intervals. Is provided.
5 is a plan view of the connecting reinforcing member 15, FIG. 6 is a cross-sectional view taken along the line BB in FIG. 4 after reinforcement, and FIG. 7 is a cross-sectional view taken along the line BB in FIG. FIG. As shown in FIG. 5, the connection reinforcing material has adhesive surfaces 17 at both ends of the band-shaped connecting portion 19. The bonding surface 17 is obtained by amplifying the end portion of the connecting portion 19.
First, the reinforcement shown in FIG. 6 will be described. In FIG. 6, the square member 21 is reinforced using a plurality of connection reinforcing members 15, two sheet-like reinforcing members 27, an adhesive 9, and an adhesive 11.
The plurality of connection reinforcing members 15 are respectively passed through the plurality of holes 25 on both sides of the square member 21 in a state where the bonding surface 17 is rounded with the connecting portion 19 as an axis. Then, the bonding surface 17 is expanded when the connecting portion 19 reaches the position of the hole 25. The adhesive surface 17 of the connection reinforcing member 15 is temporarily attached to the square member 21 using the adhesive 11.
The two reinforcing members 27 are respectively installed so as to cover the side surface 28 that is not adjacent to the flat member 23 among the side surfaces of the square member 21. Both ends of the reinforcing member 27 are placed on the outside of the bonding surface 17 of the connecting reinforcing member 15. Both ends of the reinforcing member 27 are bonded to the bonding surface 17 of the connecting reinforcing member 15 using the adhesive 9.
Next, the reinforcement shown in FIG. 7 will be described. In FIG. 7, the square member 21 and the flat member 23 are reinforced using a plurality of connection reinforcing members 15, two sheet-like reinforcing members 29, and an adhesive 9. As in the case of reinforcement shown in FIG. 6, the connection reinforcing member 15 is passed through the holes 25 on both sides of the square member 21 with the bonding surface 17 being rounded around the connecting portion 19 as an axis. Then, the bonding surface 17 is expanded when the connecting portion 19 reaches the position of the hole 25. The adhesive surface 17 of the connection reinforcing member 15 is temporarily attached to the square member 21 using the adhesive 11.
The reinforcing material 29 is installed so as to continuously cover the side surface 30 a of the square member 21 and the side surface 30 b of the flat member 23. The reinforcing material 29 is bonded to the connecting reinforcing material 15 using the adhesive 9 at a position overlapping the bonding surface 17 of the connecting reinforcing material 15.
The reinforcing material 27 and the reinforcing material 29 are, for example, a sheet material having extensibility such as a fiber type or a rubber type. The connection reinforcing material 15 is made of a material having a strength for transmitting a tension applied to the reinforcing material 27 or the reinforcing material 29 on both sides through the holes 25. The adhesive 11 temporarily attaches the connecting reinforcing material 15 to the square member 21 and is devised so as not to be excessively bonded. The adhesive 9 is made of a material that allows the connection reinforcing material 15 and the reinforcing material 27 and the connection reinforcing material 15 and the reinforcing material 29 to sufficiently transmit tension to each other.
As described above, in the second embodiment, a plurality of holes 25 are provided in the joint portion between the adjacent square member 21 and the flat member 23, and the connection reinforcing material 15 is passed through the hole 25. Transmits tension in the circumferential direction to enhance the reinforcement effect. The second embodiment can be used for a member having an arbitrary shape with undulations and irregularities.
Instead of the connection reinforcing member 15, a belt-like polyester belt 99 as shown in FIG. 24 may be used. The material of the polyester belt 99 may be a polyester fiber used for a strap or the like. The strength of a reinforcing sheet such as a civil engineering sheet is 500 to 1000 kgf per 3 cm width, but the polyester belt 99 has a strength of about 15000 kgf per 5 cm width. By passing the polyester belt 99 through the hole 25, the tension acting on the sheet-like reinforcing material 27 and the reinforcing material 29 can be transmitted with a small cross section.
Also, when the effect of the reinforcing structure shown in FIG. 6 or 7 is insufficient, the same reinforcing structure can be used repeatedly in order to increase the amount of reinforcement.
Next, a third embodiment will be described. FIG. 8 shows a perspective view of the flat member 31 to be reinforced. The flat member 31 is, for example, a wall. The flat member 31 is provided with a plurality of holes 33 penetrating the member thickness at grid-like locations. FIG. 9 is a perspective view of the connection reinforcing member 35, and FIG. 10 is a sectional view of the vicinity of the hole 33 of the flat member 31 after reinforcement.
As shown in FIG. 9, the connection reinforcing member 35 has adhesive surfaces 37 at both ends of a shaft-like connecting portion 39. The adhesive surface 37 is provided in a trumpet shape perpendicular to the axial direction of the connecting portion 39. In FIG. 10, the flat member 31 is reinforced using a plurality of connection reinforcing members 35, two sheet-like reinforcing members 41, and an adhesive 9.
The connection reinforcing member 35 is passed through the plurality of holes 33 of the flat member 31 in a state where the bonding surface 37 is rounded around the connecting portion 39 as an axis. Then, the bonding surface 37 is widened when the connecting portion 39 reaches the position of the hole 33. A reinforcing member 41 is installed outside the adhesive surface 37 so as to cover both side surfaces 32 of the flat member 31. The bonding surface 37 is bonded to the reinforcing material 41 using the adhesive 9.
The reinforcing material 41 is, for example, an extensible sheet material such as fiber or rubber. The connection reinforcing member 35 is made of a material having a strength for transmitting tension applied to the reinforcing members 41 on both sides via the holes 33. The adhesive 9 is made of a material that allows the connection reinforcing material 35 and the reinforcing material 41 to sufficiently transmit tension to each other.
As described above, in the third embodiment, a plurality of holes 33 are provided in the flat member 31, and tension is transmitted between the side surfaces 32 through the connection reinforcing material 35 in the holes 33, thereby enhancing the reinforcing effect. The third embodiment can be used not only for a wall but also for a member having an arbitrary shape such as a hollow tube having no undulation or unevenness on the surface.
In order to facilitate passage through the hole 33, a notch may be formed in the adhesive surface 37 of the connection reinforcing material 35.
As in the second embodiment, a polyester belt 99 as shown in FIG. 24 can be used as an alternative to the connection reinforcing member 35.
Next, a fourth embodiment will be described. FIG. 11 is a perspective view of the H-shaped member 43 after reinforcement. As shown in FIG. 11, the H-shaped member 43 is reinforced using a reinforcing material 45 and a granular filler 47.
Around the H-shaped member 43, a sheet-shaped reinforcing material 45 is provided in a cylindrical shape with a space provided. A space between the H-shaped member 43 and the reinforcing material 45 is filled with a granular filler 47. For the reinforcing material 45, for example, a fiber material, a rubber material, or the like is used. For the filler 47, for example, natural granular materials such as sand and artificial granular materials such as resin are used.
Since the granular filler 47 transmits stress to the reinforcing material 45 while being deformed with energy loss, unlike the conventional reinforcing method such as continuous fiber or iron winding, the filler 47 is made of resin or adhesive. There is no need to fix. Even when bonding, fixing, or the like is performed for construction reasons, it may be temporarily attached so that the shape is maintained under a normal weight or a slight earthquake.
The fourth embodiment can be used for reinforcing members other than the H-shaped member 43 having a complicated cross-sectional shape. In the fourth embodiment, the granular filler 47 transmits this to the reinforcing member 45 when the member is about to deform with an apparent volume expansion, thereby enhancing the reinforcing effect. Further, for example, the effect of protecting the H-shaped member 43 from heat can be added by using an inorganic non-combustible material having a large heat capacity.
Note that the reinforcing method of the fourth embodiment can reinforce any member having a complicated cross-sectional shape, not limited to the H-shaped member 43.
Next, a fifth embodiment will be described. FIG. 12 is a perspective view of the hollow member 49 after reinforcement. As shown in FIG. 12, the hollow member 49 is reinforced using a reinforcing material 45 and a granular filler 47.
On the surface around the hollow member 49, a sheet-like reinforcing material 45 is installed in a cylindrical shape. The hollow member 49 is filled with a granular filler 47. For the reinforcing material 45, for example, a fiber-based or rubber-based sheet material or the like is used. For the filler 47, for example, natural granular materials such as sand and artificial granular materials such as resin are used.
The granular filler 47 is installed for the purpose of filling the gap of the hollow member 49, but transmits stress to the reinforcing material 45 while being deformed with energy loss, so as in the conventional concrete-filled steel pipe method, It is not necessary to solidify the material such as concrete filled inside.
In the fifth embodiment, when a hollow member is reinforced, the reinforcing effect is enhanced by installing a granular filler 47 inside. The filler 47 has a role of transmitting the apparent volume expansion to the reinforcing member 45 when the hollow member 49 is about to break with energy loss. The cross-sectional shape of the hollow member reinforced by the reinforcing method of the fifth embodiment is not limited to a circle.
In the fourth and fifth embodiments, the reinforcing methods of the first to third embodiments may be used in combination for reinforcing the H-shaped member 43, the hollow member 49, and the like using the filler 47. .
Next, a sixth embodiment will be described. FIG. 13 is a perspective view of the seismic isolation device 55. The seismic isolation device 55 includes a reinforcing member 45 and a granular filler 47. As the reinforcing material 45, for example, a sheet material or a belt-like material that is extensible such as a fiber type or a rubber type is used. For the filler 47, for example, natural granular materials such as sand and artificial granular materials such as resin are used. The seismic isolation device 55 is a case where the cross-sectional area of the H-shaped member 43 is close to zero in FIG.
In the seismic isolation device 55, when the filler 47 is deformed with an apparent volume expansion, the reinforcing member 45 causes the circumferential compressive force to act on the filler 47 due to elasticity, thereby restraining the apparent volume expansion. By using a high ductility material as the reinforcing material 45, the seismic isolation device 55 can withstand a large deformation and the absorbed energy increases.
14 to 16 are elevation views of the structure 53 using any of the seismic isolation devices 55, 55a, and 55b. In FIG. 14, seismic isolation devices 55, 55a, and 55b are installed on a layer 57 in the upper structure 54 of the structure 53 constructed on the ground 51. The seismic isolation devices 55, 55a, 55b installed in the layer 57 support the load on the floor like a large pillar and prevent the structure 53 from collapsing during a large earthquake.
In FIG. 15, seismic isolation devices 55, 55 a, 55 b are installed in a layer 57 a between the foundation 59 installed on the ground 51 and the upper structure 54 of the structure 53. The seismic isolation devices 55, 55a and 55b shown in FIG. 15 use a large energy absorbing function and are used as seismic isolation devices.
In FIG. 16, seismic isolation devices 55, 55a, 55b are installed in a layer 57b between a foundation 59 (not shown) and the supporting ground / rock 64. In FIG. 16, the normal pile 61 installed on the ground 51 and the seismic isolation devices 55, 55a, 55b are used in combination as the pile of the structure 53. The seismic isolation devices 55, 55a and 55b shown in FIG. 16 are used as piles having a seismic isolation function and a large settlement prevention function.
FIGS. 17 and 18 are a vertical sectional view in the vicinity of the seismic isolation device 55b and a vertical sectional view in the vicinity of the seismic isolation device 55a installed in the layer of the structure as shown in FIGS. 14 to 16, respectively. is there. FIG. 19 is a horizontal sectional view of the seismic isolation device 55a, and FIG. 20 is a horizontal sectional view of the seismic isolation device 55b.
As shown in FIGS. 17 and 18, the seismic isolation devices 55a and 55b are installed as upper and lower member columns on the layer 57 and / or the layer 57a between the foundation 59 and the upper structure 54, or the layers of the ground 51 At 57b, it is installed as a pile. The upper and lower members 63 of the layers 57 and 57a are a slab, a beam, a foundation 59, and the like, respectively. In the layer 57b, instead of the lower member 63, there is a ground or a rock 64.
As shown in FIG. 19, the seismic isolation device 55 a is formed of a granular filler 47, a reinforcing material 45, and the like, similar to the seismic isolation device 55. The filler 47 is made of a resin that has a large energy absorption function and particles are not easily crushed, and the reinforcing material 45 is made of a stretchable material. The seismic isolation device 55a has a spherical shape on the side surface.
The seismic isolation device 55 a is composed of the reinforcing material 45, the filler 47, and the like, but reinforced concrete or a steel frame may be used instead of the filler 47. As shown in FIG. 20, in the seismic isolation device 55b, the reinforcing material 45 reinforces the periphery of the concrete 67 in which a tensile resistance material 65 such as a reinforcing bar is disposed, that is, a member made of reinforced concrete.
In this case, a filler (not shown) having a special structure may be mixed into the concrete 67. This filler has contents such as a resin that suppresses a decrease in the strength of the concrete. In the process in which the concrete 67 is crushed by the action of repeated loads, the content of the filler oozes out and suppresses a decrease in the strength of the concrete. Thereby, the fall of the resistance of seismic isolation apparatus 55b and the fall of the energy absorption capability per unit deformation are reduced, and the shape change of a structure can be suppressed.
A plurality of tensile resistance members 65 are disposed in the vertical direction inside the seismic isolation devices 55a and 55b. Both ends of the tensile resistance material 65 are embedded in the upper and lower members 63 or the upper member 63 and the lower ground or rock 64, respectively. The seismic isolation devices 55 a and 55 b are connected to the member 63, the ground and the rock 64 by the tensile resistance material 65.
When using the seismic isolation devices 55a and 55b as columns, the tensile resistance member 65 is, for example, a reinforcing bar, a steel plate, a belt-like connection reinforcing material such as a polyester belt 99 shown in FIG. When used as a pile, for example, an earth anchor or a lock anchor is used as the tensile resistance member 65. The tensile resistance material 65 is applied to a force that separates the layer 57 of the structure 53 and / or the layer 57a between the foundation 59 and the upper structure 54, and / or between the foundation and the supporting ground / rock mass 64 in the vertical direction. resist.
As shown in FIGS. 19 and 20, the horizontal cross sections of the seismic isolation devices 55a and 55b are circular, and four tensile resistance members 65 are arranged inside. The circular cross-sections of the seismic isolation devices 55a and 55b are obtained by prefetching the cross-sectional shape of a member that has been repeatedly subjected to a load. By making the horizontal cross section circular, it is possible to reduce the change in the cross-sectional shape when the reinforcing material 45 exhibits an effect, suppress the expansion and contraction that is the deformation in the axial direction, and suppress the change in the shape of the structure.
Thus, in the sixth embodiment, the seismic isolation devices 55, 55 a, 55 b newly constructed with the reinforcing material 45 and the filler 47 are placed in the upper structure 54 and / or between the upper structure 54 and the foundation 59. Or, and / or installed as a pillar or pile on the ground 21 to enhance the reinforcing effect of the structure 53. Unlike conventional seismic isolation devices, the seismic isolation devices 55, 55a, and 55b exhibit seismic isolation effects with respect to vertical, horizontal, and diagonal three-dimensional vibrations. That is, a large energy absorption function can be exhibited with respect to each cross-sectional force of axial tension, axial compression, bending, and twisting. This is an advantage not found in conventional seismic isolation functions. Although it has been difficult to use a conventional seismic isolation device as a pile having a seismic isolation function and a function of preventing a large settlement as shown in FIG. 16, according to the sixth embodiment, it can be easily implemented. .
In the seismic isolation devices 55, 55a, 55b, the number of tensile resistance members is not limited to four. The reinforcing member 45 may have a multiple structure in which, for example, a reinforcing member such as a polyester sheet or a belt is directly attached to a member with an adhesive, and the reinforcing members are further connected with an adhesive. The multiple structure will be described in detail in the seventh embodiment.
In the sixth embodiment, as shown in FIGS. 17 to 20, the tensile resistance material 65 resists the vertical pulling of the layers 57, 57a, 57b, which is a reinforced concrete wall or column. Then it is what is usually done. Since the seismic isolation device 55b can be formed by reinforcing members such as columns and walls constructed by a normal design and construction method, it is extremely easy to design and construct and is inexpensive compared to conventional seismic isolation devices. is there.
FIG. 21 is a diagram showing forces acting on the vertical members 69 of the layers 57, 57a, and 57b shown in FIGS. 14 to 16. FIG. The vertical member 69 is, for example, a pillar and a pile such as the seismic isolation devices 55, 55a, and 55b. However, in the case of piles, the lower surface is rock or ground.
The force acting on the vertical member 69 with the structure can be divided into a vertical force and a horizontal force. Further, the vertical force is divided into the weights Pw and ΔPw of the structure and the vertical component Ps of the seismic force. Pw is a force borne by the vertical member 69 in the weight of the structure above the layer 57, and ΔPw is the weight of the vertical member 69.
On the vertical member 69, as a vertical force, weight Pw + vertical seismic force Ps71 acts on the upper end, weight (Pw + ΔPw) + vertical seismic force Ps73 acts on the lower end, and horizontal seismic force Q79 acts as a horizontal force. Further, a bending moment M77 and a twisting moment Mz75 act on the upper and lower ends of the vertical member 69. The magnitude of these loads during an earthquake is determined by the rigidity of the vertical member 69. Without rigidity, the load will not work.
A similar load is also applied when the vertical member 69 is the seismic isolation device 55, 55a, 55b. Most of the conventional seismic isolation devices have limited directions in which the rigidity is large, and the direction in which the seismic isolation effect is exhibited is limited accordingly. Therefore, it is necessary to bear the energy due to the seismic force in the direction with less effect by a member other than the seismic isolation device. In particular, most of the tensile forces in the vertical direction were not rigid. In addition, some of the bendings have extremely high rigidity, and as a result of the concentration of bending moments in the seismic isolation device, there is a problem that the surrounding reinforcement is required.
On the other hand, the seismic isolation devices 55a and 55b according to the sixth embodiment have a structure as shown in FIGS. 17 to 20, and use a normal member design method and construction method to pull up and down. Not only the rigidity but also the horizontal rigidity, bending rigidity and torsional rigidity in any direction of the structure can be easily provided. In the case of the seismic isolation device 55, the method of the eighth invention is used. A major feature of the sixth embodiment is that a large energy absorbing function is imparted to the rigidity in each direction by an extensible sheet, belt, or the like. When the seismic isolation devices 55, 55a, 55b are used for seismic isolation of the structure 53, the seismic isolation devices 55, 55a, 55b may be newly installed, or existing members may be changed and reinforced to be exempted. The seismic devices 55, 55a, and 55b may be used.
Next, a seventh embodiment will be described. FIG. 22 is a view showing a part of the cross section of the member 81 after reinforcement. In FIG. 22, the member 81 is reinforced using a protective reinforcing material 83, a reinforcing material 85, a reinforcing material 87, and a protective reinforcing material 89.
The member 81 is provided with a protective reinforcing material 83, a reinforcing material 85, a reinforcing material 87, and a protective reinforcing material 89 in order from the inside. The protective reinforcing member 83 is installed to protect the reinforcing members 85 and 87 and the protective reinforcing member 89 from the action of the member 81. For example, when the member 81 is a material such as concrete that precipitates alkali, and the reinforcing members 85 and 87 and the protective reinforcing member 89 are materials such as polyester fibers having low alkali resistance, the protective reinforcing member 83 includes the member 81. A material such as a resin having an effect of preventing the precipitation of alkali from the substrate is used.
The protective reinforcing material 89 is installed to prevent deterioration of the functions of the protective reinforcing material 83, the reinforcing material 85, and the reinforcing material 87 due to the action of substances in the outside world. For example, when the protective reinforcing material 83, the reinforcing material 85, and the reinforcing material 87 are polyester fiber sheets or the like, they are easily deteriorated by ultraviolet rays. Therefore, the protective reinforcing material 89 uses a resin such as epoxy or urethane. And preventing deterioration of the internal reinforcing material. The protective reinforcing material 89 may be a fire protection zone.
The reinforcing material 85 and the reinforcing material 87 are materials having different reinforcing effects with respect to the member 81. For example, a polyester fiber or the like is used for the reinforcing material 87, and a material such as a resin or a fiber impregnated with a resin is used for the reinforcing material 85. In this case, the reinforcing material 87 exhibits a reinforcing effect up to a range where the distortion of the member 81 is large (about 15%), and the reinforcing material 85 exhibits a reinforcing effect within a range where the distortion of the member 81 is small (1% or less).
In the case where the member 81 is reinforced only with the polyester fiber, the Young's modulus of the reinforcing material is smaller than the Young's modulus of the member 81. Therefore, a thickness is required to exert the reinforcing effect when the distortion of the member 81 is small. However, by using a material such as a resin having a large Young's modulus or a material in which a fiber is impregnated with a resin, the thickness of the member 81 is less than that of a polyester fiber alone, and the strain of the member 81 is small ( 1% or less) can also exert a reinforcing effect. Further, by directly adhering the reinforcing material 85 to the surface of the member 81 or the protective reinforcing material 83, the effect can be exhibited within a small distortion range. The protective reinforcing material 83 has a function of transmitting a shearing force between the surface of the member 81 and the reinforcing material 85 as necessary. For example, a resin primer is used.
Further, by changing the mechanism for obtaining the reinforcing effect of the reinforcing material 85 and the reinforcing material 87, the reinforcing effect can be exhibited over different load conditions and deformation ranges. For example, there is a case where a method of directly sharing the shearing force of the member 81 with the reinforcing material and a method of constraining the apparent volume expansion of the member 81 are used in combination.
The reinforcing member 87 can be made of a material and a structure that exert a reinforcing effect by restraining the expansion of the apparent volume. As the reinforcing member 85, an iron plate, carbon fiber, aramid fiber, or the like is used for the purpose of improving the shear fracture resistance of the member 81 to improve the load resistance. The reinforcing member 85 reinforces the member 81 by directly transmitting the shearing force between the member 81 and the reinforcing member 85 and sharing the shearing force. Further, as the reinforcing member 85, a polyester sheet or a polyester belt that is impregnated with a resin or has an adhesive applied to the entire surface to increase rigidity can be used. In this case, there is an advantage that the reinforcing material 85 and the reinforcing material 87 can be continuously applied.
FIG. 23 is a graph showing the load deformation relationship of the member 81 when the reinforcement method in the multiple structure as shown in FIG. 22 is used. In FIG. 23, the vertical axis represents load, and the horizontal axis represents deformation. This load is a cross-sectional force of the member 81 such as an axial force, a bending moment, and a shearing force, and the deformation includes axial contraction, bending rate, shearing strain, etc. that are deformations suitable for each load. The member 81 has a load resistance against a wide range of deformation in the curve of 93 when reinforced with multiple structural reinforcement compared to the curve of 91 when not reinforced.
FIG. 23 shows that the effective deformation ranges of the reinforcing material 85 and the reinforcing material 87 do not overlap, and the load resistance is slightly reduced between the effective range 95 of the reinforcing material 85 and the effective range 97 of the reinforcing material 87. Here is a general example where By overlapping the effective deformation ranges of the reinforcing material 85 and the reinforcing material 87, it is possible to avoid a reduction in load resistance.
In the seventh embodiment, by using multiple reinforcing materials having different characteristics in the surroundings, a reinforcing effect can be exerted against a wide range of member load conditions and external environmental conditions. The member 81 is not limited to a concrete member or the like, but may be a filler 47 as shown in FIG. 11 and FIG. In this case, a material having an effect equivalent to that of the protective reinforcing material 83 may be selected for the filler 47 and the protective reinforcing material 83 may be omitted.
As the reinforcing member 85 that directly adheres to the surface of the member 81 or the protective reinforcing member 83, a belt-like reinforcing member having high strength and rigidity, such as the polyester belt 99 shown in FIG. 24, can be used. Since the polyester belt 99 can be woven with a structure that increases the Young's modulus per unit width as compared with the polyester sheet, the polyester belt 99 can be used as a reinforcing material 85 that exhibits an effect at a small strain stage. For example, in a tensile test result of a polyester belt 99 having a width of 64 mm and a thickness of 4 mm, the strain is 2% when 2500 kgf is applied.
When the polyester belt 99 is used as the reinforcing member 85, the pillar 105 shown in FIGS. 25 to 28 corresponds to the member 81 shown in FIG. The reinforcing method using the polyester belt 99 shown in FIGS. 25 to 28 will be described in the eighth embodiment described later.
Next, an eighth embodiment will be described. 24 is a plan view of the polyester belt 99, FIGS. 25 and 26 are perspective views showing an example of the pillar 105 reinforced with the belt-like reinforcing material 101, and FIG. 27 is a vertical view of the pillar 105 shown in FIG. FIG.
First, the reinforcement shown in FIG. 25 will be described. In FIG. 25, a plurality of strip-shaped reinforcing members 101 are installed so as to go around the pillar 105 at a predetermined interval. The ends of the belt-shaped reinforcing material 101 around the column 105 are connected to each other by either or both of a bonding that is a mechanical joint and a fastener. When a mechanical joint is used, a reinforcing effect can be obtained in a short period of time, which is suitable for emergency reinforcement immediately after an earthquake. Moreover, the effect which controls the crack of the direction which adhere | attaches the strip | belt-shaped reinforcement material 102 to a member axial direction and cross | intersects this can be anticipated.
Next, the reinforcement shown in FIGS. 26 and 27 will be described. The belt-like reinforcing material 101 is wound around the surface of the column 105 shown in FIGS. 26 and 27 without any gap. The winding effect can be enhanced by winding in the direction of arrow D while applying tension to the strip-shaped reinforcing material 101 in the direction of arrow C. The strip-shaped reinforcing material 101 is directly bonded to the column 105. In addition, chamfering for avoiding fiber breakage at the corner portion of the column 105 is not particularly required, but a strip-shaped reinforcing material (not shown) is bonded in parallel to the side of the corner portion of the member to reinforce the side portion. The effect of relieving stress concentration on the material can be expected.
As shown in FIG. 27, the belt-like reinforcing member 101 is wound in a spiral shape so that the upper end 107 and the lower end 111 of the column 105 are parallel to the circumference of the member, and the general part 109 is advanced so as to advance by the belt width in one round. It can be wound evenly without gaps. Further, the reinforcing effect can be enhanced by changing the winding direction (right-handed, left-handed) and installing the strip-shaped reinforcing material 101 in two layers and three layers. At this time, after the first layer is wound, the adhesive is applied to the entire surface, and the second layer is wound with a half-width shift on the entire surface.
FIG. 28 is a cross-sectional view of the vicinity of the surface of the pillar 105 shown in FIGS. As shown in FIG. 28, the belt-like reinforcing material 101 is directly attached to the column 105 using an adhesive 113.
For example, a polyester belt 99 shown in FIG. 24 is used for the belt-like reinforcing material 101 shown in FIGS. As described in the description of the second and seventh embodiments, the material of the polyester belt 99 is a polyester fiber used for a strap or the like. Since the polyester belt 99 has higher rigidity and strength than the civil engineering sheet, the polyester belt 99 is used in consideration of suppressing an increase in the crack width of the column 105 and controlling the apparent volume deformation within a small strain range.
Next, a method of calculating the reinforcement amount in the reinforcement that suppresses the crack width in a range where the distortion of the column 105 is small will be described. FIG. 29 is a view showing the relationship between the effective adhesion lengths of the belt-like reinforcing material 101 and the crack 115.
When a member to which bending, axial force, shearing force or the like acts locally breaks, a crack 115 is generated on the surface of the member. In FIG. 29, the crack 115 is generated in a state where the belt-like reinforcing material 101 is directly attached to the surface of the column 105. The belt width 119 of the belt-shaped reinforcing material 101 is w. The belt-like reinforcing material 101 is subjected to a force acting to push the crack 115, that is, a tension 121 acting q per piece. In FIG. 29, the crack width 117 is suppressed to d or less by the effect of the band-shaped reinforcing material 101.
There is stress concentration in the vicinity of the crack 115. The width 123 (a) centered on the crack 115 is the length of the portion where the adhesive 113 or the nearby member surface is sheared and loses the adhesive effect, and is hereinafter referred to as the free length. The restraint length 125 (b) is a natural restraint length of the column 105 and is a length measured from the free end. Accordingly, the belt-like reinforcing material 101 is bonded to the column 105 with a fixing length s = ba.
Here, the restraint length 125 is the length of one side in the case of a rectangular cross section such as the pillar 105, and the peripheral portion around a central angle of 90 degrees in the case of a circular cross section. When these lengths are extremely larger than the belt width 119 (w) of the belt-like reinforcing member 101, the length of the actually acting adhesive force is not zero.
When the crack 115 is near the center of a surface having a member having a rectangular cross section, the restraint length 125 extends to the other surface of the member.
When the rigidity of the belt-shaped reinforcing member 101 is k, the following relationship exists between the free length a, that is, the width 123, the crack width 117 (d), and the tension 121 (q).

When the average shearing force between the belt-like reinforcing material 101 and the column 105 within the fixing length s = ba is τ,

It is.
If the free length a is eliminated from the equations (1) and (2), the following quadratic relationship exists between the tension 121 (q), the average shear force τ, and the crack width 117 (d).

This relationship is related to the maximum crack width d _max There are two solutions q below. Since the larger solution is realized first, if this is adopted, q is the maximum value q according to the crack width 117 (d). _max And the minimum value q _min Between.

Minimum value q _min Crack width d corresponding to _max Is

It is.
Crack width is d _max Beyond, Equation 3) has no solution. That is, such a mechanism does not hold. From the above relationship, the maximum value q when the force to push and spread the crack 115 is shared by the belt-shaped reinforcing material 101 _max And the minimum value q _min Therefore, structural reinforcement utilizing the above mechanism can be designed. The values of Equation 4) to Equation 6) are proportional to the adhesive force τ (average shear force) between the member such as the column 105 and the belt-like reinforcing material 101.
In the case where an inexpensive material having excellent extensibility such as the polyester belt 99 is used as the belt-like reinforcing material 101, the Young's modulus as the material is about one-tenth that of concrete and about one-hundredth that of iron. Therefore, even if the adhesive 113 having a large average shearing force τ is used for bonding, it is difficult to share the shearing force that is elastically applied to the member without causing the crack 115. However, when a reinforcing effect within a small deformation range is particularly required, an epoxy resin adhesive is used after the polyester belt or the like is impregnated with a resin to increase the rigidity of the reinforcing material.
In FIG. 28, for example, the belt-like reinforcing material 101 is a polyester belt 99 having a width of 64 mm and a thickness of 4 mm, the column 105 is a reinforced concrete column having a restraint length 125 of b = 30 cm, and the adhesive 113 is made of Toyo Polymer. The epoxy urethane adhesive Rubylon is used. At this time, average shear force τ = 10 kgf / cm ² The belt width 119 of the belt-shaped reinforcing material 101 (polyester belt 99) is w = 6.4 cm, the restraint length 125 is b = 30 cm, and the rigidity k of the belt-shaped reinforcing material 101 (polyester belt 99) is k = 153000 kgf / cm. ² It is.
Maximum value q using equations 4) to 6) _max , Minimum value q _min Maximum crack width d _max Is the maximum value q _max = 1920kgf, minimum q _min = 960 kgf, maximum crack width d _max = 0.12 cm.
Therefore, when this reinforcement is carried out, the maximum crack width d _max = 1.2 mm can be constrained, and the tension 121 per belt-like reinforcing material 101 (polyester belt 99) at this time is q = 0.9 tf.
FIG. 30 is a schematic view of the column 105 subjected to axial force, bending and shearing, and FIG. 31 is a diagram showing a force for expanding the crack 115 generated in the column 105. In the state where the axial force 129 (P) is continuously applied to the column 105 reinforced with the polyester belt 99 as the belt-like reinforcing material 101 by the method shown in FIG. 27, a horizontal force is applied, and a bending moment 131 (M), The reinforcing effect will be described below when the shearing force Q is repeatedly generated.
The pillar 105 is assumed to be a pillar of a normal construction part. The shearing force 127 (Q) acts horizontally at an intermediate height (h / 2) of the height h of the column 105, and the upper and lower ends of the column 105 slide horizontally so as not to rotate. . As a result, a shearing force (a resultant force Q) and an axial force (a resultant force P) that are uniform in the horizontal direction are generated inside the column 105. The bending moment is M = Qh / 2 at the upper end, zero in the middle, and −M at the lower end.
Maximum shearing force Q determined by shearing force 127 (Q) from the state of the reinforcing bars and concrete of the column 105 _max The crack 115 occurs in the direction of the angle θ137. The force for spreading the crack 115 in the horizontal direction is a shearing force 127 (Q) acting on the column 105. It is considered that this force is borne by the band-shaped reinforcing material 101 in the range indicated by the arrow c133. Since the band-shaped reinforcing material 101 has a width of w and a tension per line is q, the resultant force Q of the band-shaped reinforcing material 101 in the range of the arrow c133 is Q = q · 2C / w.
However, since the pillar 105 has a rectangular cross section, a coefficient of 2 was used on the assumption that both the front surface and the back surface work. The length C of the arrow c133 is C = btan θ from FIG. In general, the shearing force Q is borne even inside the member, but the belt exhibits a remarkable effect. _max Beyond nearby deformation, it is assumed that almost all shear forces are borne by the belt tension.
If the angle θ137 = 45 degrees, the width 135 of the column 105 is b (restraint length) = 30 cm. Therefore, the maximum value q when using the polyester belt 99 (width 64 mm, thickness 4 mm) previously calculated by equations 4) to 6) _max , Minimum value q _min Horizontal force Q corresponding to _max , Q _min Q _max = Q _max 2b / w = 18000kgf, Q _min = Q _min 2b / w = 9000 kgf. Therefore, the width of the crack 115 is d due to the effect of this reinforcement. _max In a range not exceeding 1.2 mm, a horizontal resistance of 9 tf or more can be maintained.
Next, with respect to the column 105 without reinforcement and the column 105 reinforced with the above-described polyester belt 99 (width 64 mm, thickness 4 mm) as the belt-like reinforcing member 101 shown in FIG. 27, under the conditions shown in FIG. The results of a horizontal repeated force test with displacement control will be described. However, the concrete strength of the pillar 105 is 135 kgf / cm. ² The axial rebar ratio is 0.56%, the shear reinforcing bar ratio is 0.08%, the axial force is constant, and is 37 tf (axial force ratio 0.3).
FIG. 32 is a schematic diagram showing the deformation of the pillar 105. The horizontal displacement of the column 105 is defined as the horizontal displacement δ. _h 139, the vertical displacement is the vertical displacement δ _v Assuming 141, the results shown in FIGS. 33 to 38 were obtained through experiments. FIG. 33 is a diagram showing an envelope of the horizontal force Q of the column 105 and the displacement history. FIG. 34 is a diagram showing the relationship between the horizontal displacement, vertical displacement, and horizontal force of the column 105, and FIG. 35 is a diagram showing the restoring force characteristic relationship of the column 105.
33, the horizontal axis represents the horizontal displacement δh (139) of the column 105, and the vertical axis represents the horizontal force Q (shearing force 127). The horizontal axis in FIG. 35 represents the horizontal displacement δh (139) and the deformation angle of the column 105, and the vertical axis represents the horizontal force Q (shearing force 127).
In FIG. 33, the envelope when the column 105 is not reinforced with the belt-shaped reinforcing material 101 is the curve without reinforcement 143a, and the envelope when reinforced is the curve with reinforcement 143b. The envelopes shown in 143b with reinforcement are envelopes of points such as the Great Hanshin Earthquake equivalent 157a, the Great Hanshin Earthquake equivalent 157b, the Great Hanshin Earthquake equivalent 157c, the Great Hanshin Earthquake equivalent 157d of the history loop 153 shown in FIG. is there.
In FIG. 34, the horizontal axis represents the horizontal displacement δ _h (139), the upward vertical axis is the horizontal force Q (shearing force 127), and the downward vertical axis is the vertical displacement δ. _v (141) is shown. Unreinforced 143a and reinforced 143b have the same envelope as shown in FIG. 33 without reinforced 143a and reinforced 143b. No reinforcement 145a is the vertical displacement δ of the column 105 that was not reinforced by the belt-shaped reinforcement. _v 145b with reinforcement is the vertical displacement δ of the column 105 reinforced with the belt-like reinforcing material 101 (polyester belt 99). _v It is a curve which shows.
As shown in FIGS. 33 and 34, the maximum horizontal force in the case of no reinforcement 143a is Q _max1 The maximum horizontal force in the case of 143b with reinforcement is Q _max2 , Q is the minimum horizontal force _min Then, from the experimental data, the maximum horizontal force in the case of 143a without reinforcement is Q _max1 = 17.5 tf. The maximum horizontal force in the case of 143b with reinforcement is Q _max2 = 18tf, minimum horizontal force is Q _min = 7 tf.
In FIG. 34, the line of the unreinforced 143a indicating the horizontal force Q of the column 105 without reinforcement, the vertical displacement δ. _v For the line of 145a without reinforcement, the horizontal force Q is Q _max1 It has plummeted from the moment. This is because the reinforced pillar 105 is Q _max2 From the horizontal displacement corresponding to _min In the horizontal displacement region up to this point, the above-mentioned assumption that most of the shearing force is borne by the reinforcing effect of the belt-like reinforcing member 101 (polyester belt 99) is supported.
Minimum horizontal force Q at 143b with reinforcement _min It is an experimental error that the experimental data of Fig. 30 and Fig. 31 is smaller than the calculated value 9tf using the model shown in Figs. It is also conceivable that a decrease in strength occurs on the adhesive surface with (99). Maximum shear force Q _max2 Is a value substantially equal to the calculated value 18tf.
As shown in FIG. 34, the horizontal displacement δ of the column 105 _h Is the displacement amplitude δ _hc In the case of 147, the horizontal force inflection point 149 has a vertical displacement δ in the curve of the reinforced 143b indicating the horizontal force Q. _v There is a vertical displacement inflection point 153 in the curve of 145b with reinforcement. Displacement amplitude δ _hc 147 is the horizontal displacement δ near the 157c equivalent to the Hyogoken-Nanbu Earthquake triple in the history loop 153 shown in FIG. _h That is, it is about 140 mm (the deformation angle is 0.15 rad).
FIG. 36 shows the cumulative horizontal displacement Σδ of the column 105. _h FIG. FIG. 37 is a detailed view of FIG. In FIG. 36, the horizontal axis represents the horizontal cumulative displacement Σδ _h And the vertical axis represents the history absorbed energy W.
Cumulative horizontal displacement Σδ shown on the horizontal axis of FIGS. 36 and 37 _h Was calculated by the following formula. Here, i is the number of data recording steps, and n is the current number of steps. Cumulative horizontal displacement Σδ _h Is calculated as an index indicating the position on the history loop 153 shown in FIG.

The history absorption energy W shown on the vertical axis was calculated by the following equation. The history absorption energy W is a work performed by the horizontal force Q, that is, the shear force 127.

If the axial force 129 that the pillar 105 with the structure is responsible for is P, the mass m corresponding to this can be expressed as m = P / g using the gravitational acceleration g. Therefore, among the energy that is input to the structure and consumed until the vibration is finished, the work E performed by the shearing force 127 acting on the column 105 is approximately the following using the velocity response spectrum Sv of the earthquake motion. It is expressed by an expression.

The curve of the history absorption energy 157 shown in FIG. 36 represents the history absorption energy calculated by the equation 8) from the history loop 153 of the experimental result shown in FIG. The values indicated by the straight lines corresponding to the Great Hanshin Earthquake equivalent 159a and the Great Hanshin Earthquake five times equivalent 159b are calculated by Equation 9) for comparison with the curve of the history absorbed energy 157. In FIG. 37, the values of 159c equivalent to the Hanshin Great Earthquake twice and 159d equivalent to the Great Hanshin Earthquake triple calculated by Equation 9) are further shown. In using Equation 9, the velocity response spectrum used was Sv = 90 cm / s, which is a value in the Kobe Ocean Meteorological Observatory record with a natural period of 0.3 seconds.
FIG. 38 shows the cumulative horizontal displacement Σδ calculated by Equation 7). _h And vertical displacement δ _v It is a figure which shows the relationship. In FIG. 38, the horizontal axis represents the horizontal cumulative displacement Σδ _h , The vertical axis is the vertical displacement δ _v (141) is shown. As described in FIG. 34, the horizontal displacement is the displacement amplitude δ. _hc 147, that is, about 140 mm, there is a vertical displacement inflection point 153. At this time, the cumulative horizontal displacement Σδ _h Is about 1500 mm. As shown in FIG. 38, the vertical displacement δ is up to about 1500 mm at the vertical displacement inflection point 153. _v Is 5 mm (strain 0.5%) or less.
From this experiment, the following can be said.
(1) Low-strength concrete (135kgf / cm, which is difficult to reinforce conventionally) ² ) Showed a reinforcing effect.
(2) The reinforcing effect was continuously exhibited from a small strain range to a large deformation.
(3) In the curve of 143b with reinforcement shown in FIG. 33, two inflection points (Q = Q _max2 And Q = Q _min That is, a horizontal force inflection point 149) was confirmed.
(4) Vertical displacement δ in the curve of 145b with reinforcement shown in FIG. _v One inflection point (vertical displacement inflection point 153) was confirmed. This is the horizontal force inflection point 149 described in (3) (Q = Q _min ). It should be noted that the vertical displacement inflection point 153 is that the concrete is cumulatively damaged by the repeated load, the concrete strength is lowered, the adhesive strength τ between the strip-shaped reinforcing material 101 (polyester belt 99) and the concrete surface of the column 105 is lowered, and the crack width 117 is the limit d _max As a result, the mechanism of Formulas 1 to 6 is no longer valid, and as a result, the cross-sectional shape of the column 105 starts to change, and the mechanism shifts to a mechanism that causes large axial deformation.
(5) Second inflection point of horizontal force Q, that is, Q = Q _min Until the horizontal inflection point 149 is reached, that is, the vertical displacement δ _v Until the vertical displacement inflection point 153 is reached, the vertical displacement δ _v (The axial contraction of the column 105) is 0.5% or less, which is practically an allowable range in which the structure can be reused after an earthquake.
(6) When no reinforcement is applied (in the case of no reinforcement 143a and 145a shown in FIGS. 33 and 34), the vertical displacement δ before the history absorbed energy equivalent to the Great Hanshin Earthquake. _v The structure suddenly expanded and the structure is believed to have collapsed.
(7) In the case of reinforcement, the vertical displacement δ is changed until the hysteresis absorption energy 157 shown in FIGS. 36 and 37 becomes hysteresis absorption energy equivalent to about 2.5 times the Great Hanshin Earthquake. _v Is 0.5% or less, and is practically an allowable range in which structures can be reused after an earthquake.
(8) When reinforced, as shown in FIG. 38, the history absorbed energy equivalent to about 2.5 times the Great Hanshin Earthquake (cumulative horizontal displacement Σδ _h Exceeds about 1500 mm), the vertical displacement δ _v Gradually expands. However, as shown in FIGS. 34 and 35, since the horizontal proof stress is increased and the absorbed energy per cycle is increased, the vibration damping effect is enhanced and there is a large collapse preventing effect.
According to the eighth embodiment, the method of directly adhering the belt-like reinforcing material 101 such as the polyester belt 99 to the member such as the pillar 105 is the generation of the crack 115 as shown in the experimental results of FIGS. From the later small deformation to the large deformation, it continuously exerts the reinforcing effect.
Conventionally, when reinforcing a member by rolling it up, a reinforcing material such as carbon fiber or a wound iron plate having rigidity equal to or greater than the rigidity of the main mechanical elements constituting the member is used to prevent the occurrence of cracks. However, in the eighth embodiment, the crack width 117 is set to an effective value, for example, about 2 mm, instead of trying to suppress the generation of the crack 115 on the member surface. By holding down, the function deterioration of the member is controlled, and the usability and safety of the structure are maintained.
The method of directly adhering to the member surface using a material having high rigidity such as the polyester belt 99 aims to increase the effect of maintaining the shape of the member within the range of deformation accompanied by the finite crack 115. This effect increases in proportion to the rigidity in the circumferential direction of the reinforcing material as shown in the equations 1 to 4), and is limited by the magnitude of the shearing force transmitted between the member surface and the reinforcing material. Therefore, the effect can be enhanced by directly bonding the member and the stiffener having a large rigidity.
The belt-like reinforcing material 101 used in the eighth embodiment is not limited to the polyester belt 99. Any material having the same strength and rigidity can be used.
Further, the reinforcement method of the eighth embodiment is a method of suppressing the expansion of the apparent volume of the member by controlling the increase of the crack width 117, and is theoretically equivalent to the previous application, but the shape change and Inventing a mechanism that suppresses axial strain, and demonstrating it through theoretical formulas and experiments, has great practical significance in the future.
Next, a ninth embodiment will be described. As in the first embodiment, the ninth embodiment is a method for enhancing the reinforcing effect of the uneven member and the joint between the member and the member. FIG. 39 is a perspective view showing a state in which the connecting reinforcing members 169a and 169b are installed at the joint portion between the column 161 and the beam 163. FIG. Beams 163 are joined to the left and right side surfaces 165b of the column 161.
The joint portion between the column 161 and the beam 163 is first reinforced with two sheet-like connection reinforcing members 169a and four connection reinforcing members 169b. The connection reinforcing material 169a is a sheet-like reinforcing material, and is bonded so as to cover the joint portion between the side surface 165b of the column 161 and the side surface 167a of the beam 163. The central portion of the connecting reinforcing member 169a is bonded to the side surface 165a of the column 161 and the side surface 165b adjacent to the left and right, and both ends are bonded to the side surface 167a of the beam 163.
The connecting reinforcing material 169b is a sheet-like reinforcing material, and is bonded so as to cover the joint portion between the side surface 165b of the column 161 and the side surface 167b of the beam 163. The connection reinforcing materials 169a and 169b are, for example, a sheet material having extensibility such as a fiber type or a rubber type.
For the connection reinforcing materials 169a and 169b, a belt-shaped reinforcing material such as a polyester belt 99 may be used instead of a sheet-shaped reinforcing material. Regardless of whether a sheet material or a belt-shaped reinforcing material is used, the thickness, width, length, and the like of the connecting reinforcing materials 169a and 169b are set to dimensions corresponding to the necessary amount of reinforcement.
The method of adhering the connecting reinforcing members 169a and 169b to the pillar 161 and the beam 163 may be temporarily attached as in the reinforcing member 7a of the first embodiment, but like the reinforcing member 85 of the seventh embodiment. In addition, it is possible to use an adhesive which is expected to have strength. In general, the displacement amplitude of a structure greatly depends on the deformation of the joint portion between the members. Considering that the amount of reinforcement is determined by the method shown in step 209 of FIG. It is practical to use.
FIG. 40 is a perspective view showing a state in which strip-shaped reinforcing members 171a and 171b are installed at the joint between the column 161 and the beam 163. FIG. In FIG. 40, one strip-shaped reinforcing member 171a and two strip-shaped reinforcing members 171b are installed so as to cover the connecting reinforcing members 169a and 169b installed as shown in FIG. The band-shaped reinforcing material 171 a is installed around the thicker member, that is, the column 161. The belt-shaped reinforcing material 171a is obliquely straddled across the joint portion between the column 161 and the beam 163, and is continuously wound around the upper portion and the lower portion of the joint portion. The belt-shaped reinforcing material 171 b is installed around the member on the narrow side, that is, the beam 163. The band-shaped reinforcing material 171b is wound around the beam 163 joined to the left and right of the column 161 independently.
Repeat this method to increase the amount of reinforcement to the required amount. In FIG. 40, the band-shaped reinforcing members 171a and 171b are doubled and are laid at the joint between the column 161 and the beam 163.
For bonding the strip-shaped reinforcing members 171a and 171b to the column 161 and the beam 163, bonding with high strength as used in the previous application and the present application is used. FIG. 41 is a view showing a cross-sectional view of the joint portion between the column 161 and the beam 163 where the connecting reinforcing material 169b and the like are installed. Band-shaped reinforcing materials 171a and 171b are wound around the sheet-shaped connecting reinforcing material 169b. The column 161 or the beam 163 and the sheet-like connecting reinforcing material 169b, the connecting reinforcing material 169b, and the belt-like reinforcing materials 171a and 171b are bonded so as to transmit each other's tension via the shear resistance of the bonding surface. The columns 161 and the beams 163 are connected to the connecting reinforcing material 169a, and the connecting reinforcing material 169a and the band-shaped reinforcing materials 171a and 171b are bonded in the same manner.
If necessary, the reinforcing material 173 a is wound around the pillar 161 and the reinforcing material 173 b is wound around the beam 163. The reinforcing materials 173a and 173b are extensible sheet materials and strip-shaped materials.
As described above, in the ninth embodiment, the connection reinforcing members 169a and 169b are provided at the joint portion between the column 161 and the beam 163 to enhance the reinforcing effect between the members. Further, the strip-shaped reinforcing material 171a is wound around the pillar 161, which is a thicker member, and the strip-shaped reinforcing materials 171a and 171b are wound around the column 161 and the beam 163 in multiple layers. Ensure the necessary amount of reinforcement.
In FIGS. 39 and 40, a cross-shaped joint is shown, but a T-shaped joint or the like can be applied in the same manner. Furthermore, it is effective not only for the combination of a column and a beam but also for reinforcing the joint portion between other members. Moreover, it can also use together with the method of using a slit and a hole as shown to the 1st, 2nd embodiment. This is particularly effective for reinforcing joints between members having greatly different thicknesses and shapes such as slabs and beams and walls and beams. In the case where a sufficient amount of reinforcement can be obtained with only the band-shaped reinforcing members 171a and 171b, the connecting reinforcing members 169a and 169b may be omitted.
FIGS. 42 and 43 are flowcharts for designing the amount of reinforcement when a member is reinforced by the method of the present invention. A method of determining the reinforcement specifications will be described with reference to the flowcharts of FIGS. 42 and 43.
As shown in FIG. 42, first, limit conditions such as the weight, shape and function of the structure are determined (step 201). At the same time, the amplitude, period, duration, and energy of the sudden external force acting on the structure are determined (step 202). Further, a portion to be borne by a conventional material such as a reinforcing bar or concrete is determined among the sudden external forces acting on the structure (step 203).
Next, when determining a member specification (a), such as when a structure or a member is newly installed, the member specification is determined in consideration of the determination items from step 201 to step 203 (step 204). The member specifications can be determined using a normal structural design calculation method or other reinforcement guidelines.
Next, a constant load such as its own weight and a sudden external force to be borne by this method are determined (step 205). That is, the type, nature and magnitude (amplitude, period, duration, energy) of the sudden external force borne by the method, structure, and material of the present invention are determined. This is determined from the energy of the sudden external force that is determined to be received in the lifetime of the structure, which is determined in Step 201, and the energy of the sudden external force that can be withstand other than reinforcement in the method of the present invention (determined in Step 203). It is also possible to exclude a portion that is burdened with conventional materials. Therefore, when considering using the reinforcement of the present invention in the structural design at the time of new installation, the material of the member and the member specifications can be saved in consideration of this reinforcement.
In addition, when a member specification is not determined (b), such as when an existing structure or member is reinforced with a reinforcing material, the content of step 205 is determined from the items determined in step 202 and step 203. In this case as well, it can be determined that the sudden external force that the structure is expected to receive during its useful life is excluded from the sudden external force that can be withstood other than reinforcement by the method of the present invention.
Next, the amplitude and energy of the sectional force acting on the member are calculated (step 206). That is, based on the type, nature, and magnitude of the sudden external force determined in step 202, the cross-sectional force (shearing force, axial force, bending moment, etc.) acting on the member including the reinforced member and other members and the member Calculate the amplitude and magnitude of deformation (shear strain, axial strain, bending strain, etc.). At the same time, the displacement amplitude and vibration energy due to the sudden external force of the entire structure are calculated (step 207).
Strictly speaking, step 206 and step 207 are calculated by performing structural analysis calculations such as a finite element method and a frame analysis method in consideration of the restoring force characteristics of the reinforced member and other members as shown in FIG. it can. As a simplified method, as is done in normal structural design, the structural system can be simplified and an assumption such as an energy rule can be provided. Except for the fact that the target deformation range is wide compared to the conventional calculation, it can be performed in the same manner as the structural design of a member having a clear restoring force characteristic.
Next, the relationship between the reinforcement amount of the reinforced member, the restoring force characteristic, and the axial strain is determined (step 208). The content of step 208 is determined by the calculations of step 206 and step 207. At this time, generally, as indicated by a broken line in FIG. 43, feedback between step 206 and step 207 is required from step 210 to step 208.
Then, limit conditions such as function / usability / repairability after a sudden external force action such as an earthquake of the structure are determined (step 209), and the displacement amplitude and vibration energy of the structure calculated in step 207 are determined. Are compared to determine the reinforcement specifications (step 210).
In other words, the deformation of the structure calculated in Step 206 to Step 208 and the allowable deformation amount determined in Step 209 from the conditions for using the structure after the sudden external force such as an earthquake is applied. To determine the specifications for reinforcement. At this time, limit conditions such as the weight, shape, and function of the structure determined in step 201 are also taken into consideration.
With regard to a large earthquake or the like, the allowable deformation can be greatly increased as long as it does not have to collapse in step 209. On the other hand, if there is a risk of derailment or the like if the deformation is large even immediately after a major earthquake, such as a viaduct on a Shinkansen, the amount of reinforcement is determined in consideration of this.
In the first to ninth inventions, the effect of the method (previous application) for controlling the destruction of the member by placing an extensible material on the member surface with an adhesive and restraining the expansion of the apparent volume. The present invention relates to a reinforcing method, a reinforcing structure, and a seismic isolation device.
In the previous application, a low-cost material that is easy to process and bond, such as a polyester sheet, is used as the reinforcing material. The Young's modulus of these reinforcing materials is about 1/10 of concrete and about 1/100 of iron. Therefore, the effect of directly sharing a part of the load acting on the member in the elastic range in which the distortion is extremely small in the form of a reinforced concrete reinforcing bar is very small in proportion to the ratio of the above Young's modulus.
However, since the material such as iron or concrete that mainly constitutes the member yields or cracks due to the action of repeated loads, and the plastic deformation starts, the rigidity of the member decreases. The method of application exhibits a remarkable effect. That is, the material such as concrete that constitutes the member becomes a powder through a granular material, and even after iron is greatly plastically deformed or broken, these are integrated and held, such as axial force holding ability, bending and shearing, etc. The ability to resist external forces can be demonstrated.
Since the reinforced member absorbs extremely large energy in the above-described series of repeated deformation processes while maintaining rigidity, the structure can be prevented from collapsing from sudden external forces such as earthquakes. About the example of the reinforced concrete pillar, the experimental result was shown in the part of 8th Embodiment.
FIG. 44 is a diagram showing the relationship between cumulative deformation of a reinforced member and hysteresis energy absorption due to the action of repeated loads. The horizontal axis represents cumulative deformation, and the vertical axis represents history absorbed energy. Even when the member is deformed with a finite crack, the material constituting the member is partially broken by being repeatedly subjected to an external force. Therefore, since the shearing force transmitted between the member and the reinforcing material is lowered accordingly, the reinforcing effect is reduced and the effect of maintaining the shape of the member is also reduced. The destruction of the material constituting the member due to the repeated load can be measured by the work applied by the external force, that is, the history absorbed energy.
Depending on the type and amount of the material, there is a certain limit (referred to as shape retention limit energy 161), and beyond this, the material behaves in a granular form, so that the shape of the member starts to change significantly. In the member reinforced by the method of the present invention and the previous application, the cross section is circular and the overall shape is close to a shape in which spheres are connected. This significantly changes the shape of the structure.
The example of the seismic isolation devices 55, 55a and 55b shown in FIGS. 18 to 20 of the sixth embodiment minimizes the shape change after the shape retention limit energy 161 by preempting this shape. Thus, it is aimed to increase the history absorption energy region that can ensure the usability of the structure after an earthquake, that is, the energy region of the input ground motion. This shape improvement is one of the methods for enhancing the effect of the previous application.
Further, in the process before the shape retention limit energy 161, frictional force and heat are generated inside the member to destroy the material such as concrete constituting the member. As described in the description of FIG. 20 of the sixth embodiment, the special filler is mixed into the material such as concrete 67, so that the contents of the filler can be obtained by the heat and frictional force described above. It can be exuded to suppress the strength reduction of the material, and the shape retention energy 161 can be increased.
As shown in FIG. 44, it is a feature of the prior application that it can cope with a wide range of energy region and deformation region, and the method of the present invention is a method for enhancing this effect. Furthermore, when the previous application and the method of the present invention are used for the seismic isolation device, the amount of energy required to almost completely pulverize the material corresponding to the volume of the device while maintaining the rigidity while minimizing the shape change Can be absorbed. This is a very efficient method as a seismic isolation device. Furthermore, a special filler is mixed and the material is reinforced inside using energy such as heat generated by external force work in the above process, so that the seismic isolation effect can be further enhanced.
Next, a tenth embodiment will be described. In the tenth embodiment, resin is impregnated into the fiber-based sheet-like reinforcing material or the belt-like reinforcing material used in the first to ninth embodiments. FIG. 45 is a diagram showing the tensile stress-strain relationship between the reinforcing material impregnated with resin and the reinforcing material not impregnated. The vertical axis represents tension, and the horizontal axis represents elongation strain (%).
When the resin is impregnated, a curve 175 indicates a stress-strain relationship in which a polyester sheet-like woven fabric is impregnated with an epoxy resin and a tensile test is performed after the resin is cured. When not impregnated, a curve 177 indicates a stress-strain relationship in which a tensile test was performed without impregnating the same sheet-shaped woven fabric with an epoxy resin.
In FIG. 45, comparing the curves of 175 when the resin is impregnated and 177 when the resin is not impregnated, the rigidity, that is, the secant gradient of the graph, is prominent in the range of strain from 0% to about 3% when the resin is impregnated. It can be seen that it can be deformed without breaking up to a large strain range. The same test results can be obtained with a belt-shaped material made of polyester such as the polyester belt 99 shown in FIG.
The test results shown in FIG. 45 show that when the resin is impregnated, the resin deforms the fiber within a small strain range by impregnating the resin with a sheet or belt-shaped material woven with polyester fibers. This shows that there is an effect of restraining, and the rigidity is increased as compared with 177 when not impregnated. Further, when the deformation becomes large, when the resin is impregnated, 175 shows that the above-mentioned effect is lost without greatly damaging the fiber, so that the deformation performance can be maintained up to a large strain of 15% or more.
Thus, by using the reinforcing material impregnated with the resin as the sheet-like reinforcing material or the belt-like reinforcing material used in the first to ninth embodiments, a single type of material can be used within a small strain range. While enhancing the effect of suppressing deformation, it is possible to obtain a load holding effect in a large strain range. The reinforcing material of the tenth embodiment is a method that enables the reinforcing material 85 and the reinforcing material 87 of the seventh embodiment to be made of a single type of material.
Industrial applicability
As described above, the structure reinforcing structure, the seismic isolation device, and the reinforcing method according to the present invention are joined to other members or non-structural members or extremely close to each other when the members to be reinforced have undulations or irregularities. If there is a possibility that the reinforcing material may deteriorate due to the action of the member and the reinforcing material, the reinforcing material and the outside world, the case where a reinforcing effect is required from a small range of deformation to a large deformation, the case where seismic isolation reinforcement is required, etc. Suitable for use in.
[Brief description of the drawings]
FIG. 1 is a perspective view of a member to be reinforced.
FIG. 2 is a cross-sectional view taken along line AA of FIG. 1 after reinforcement.
FIG. 3 is a cross-sectional view taken along line AA of FIG. 1 after reinforcement.
FIG. 4 is a perspective view of a member to be reinforced.
FIG. 5 is a plan view of the connection reinforcing member 15.
FIG. 6 is a cross-sectional view taken along the line BB of FIG. 4 after reinforcement.
FIG. 7 is a view showing a part of the BB cross section of FIG. 4 after reinforcement.
FIG. 8 is a perspective view of the flat member 31 to be reinforced.
FIG. 9 is a perspective view of the connection reinforcing member 35.
FIG. 10 is a sectional view of the vicinity of the hole 33 of the flat member 31 after reinforcement.
FIG. 11 is a perspective view of the H-shaped member 43 after reinforcement.
FIG. 12 is a perspective view of the hollow member 49 after reinforcement.
FIG. 13 is a perspective view of the seismic isolation device 55.
FIG. 14 is an elevational view of the structure 53 using any of the seismic isolation devices 55, 55a, 55b.
FIG. 15 is an elevation view of the structure 53 using any of the seismic isolation devices 55, 55a, 55b.
FIG. 16 is an elevational view of the structure 53 using any of the seismic isolation devices 55, 55a, 55b.
FIG. 17 is a vertical sectional view of the vicinity of the seismic isolation device 55b installed in the layer of the structure as shown in FIGS.
FIG. 18 is a vertical sectional view of the vicinity of the seismic isolation device 55a installed in the layer of the structure as shown in FIGS.
FIG. 19 is a horizontal sectional view of the seismic isolation device 55a.
FIG. 20 is a horizontal sectional view of the seismic isolation device 55b made of concrete.
FIG. 21 is a diagram showing forces acting on the vertical members 69 of the layers 57, 57a, and 57b shown in FIGS. 14 to 16. FIG.
FIG. 22 is a view showing a part of the cross section of the member 81 after reinforcement.
FIG. 23 is a graph showing the load deformation relationship of the member 81.
FIG. 24 is a plan view of the polyester belt 99.
FIG. 25 is a perspective view showing an example of a column 105 reinforced with a belt-like reinforcing material 101.
FIG. 26 is a perspective view showing an example of a column 105 reinforced with a belt-like reinforcing material 101.
FIG. 27 is an elevation view of the pillar 105 shown in FIG.
FIG. 28 is a cross-sectional view of the vicinity of the surface of the pillar 105 shown in FIGS.
FIG. 29 is a view showing the relationship between the effective adhesion lengths of the belt-like reinforcing material 101 and the crack 115.
FIG. 30 is a schematic view of the column 105 subjected to axial force, bending and shearing.
FIG. 31 is a diagram showing the force for expanding the crack 115 generated in the pillar 105.
FIG. 32 is a view showing a deformation of the pillar 105.
FIG. 33 is a diagram showing an envelope of the horizontal force Q of the column 105 and the displacement history.
FIG. 34 is a diagram showing the relationship between the horizontal displacement, vertical displacement, and horizontal force of the column 105.
FIG. 35 is a diagram showing the restoring force characteristic relationship of the pillar 105.
FIG. 36 shows the cumulative horizontal displacement Σδ of the column 105. _h FIG.
FIG. 37 is a detailed view of FIG.
FIG. 38 shows the cumulative horizontal displacement Σδ _h And vertical displacement δ _v It is a figure which shows the relationship.
FIG. 39 is a perspective view showing a state in which the connecting reinforcing members 169a and 169b are installed at the joint portion between the column 161 and the beam 163. FIG.
FIG. 40 is a perspective view showing a state in which strip-shaped reinforcing members 171a and 171b are installed at the joint between the column 161 and the beam 163. FIG.
FIG. 41 is a view showing a cross-sectional view of the joint portion between the column 161 and the beam 163 where the connecting reinforcing material 169b and the like are installed.
FIG. 42 is a diagram showing a flowchart for designing the amount of reinforcement.
FIG. 43 is a diagram showing a flowchart for designing the amount of reinforcement.
FIG. 44 is a diagram showing the relationship between the cumulative deformation of the reinforced member and the history absorbed energy.
FIG. 45 is a diagram showing the tensile stress-strain relationship between the reinforcing material impregnated with resin and the reinforcing material not impregnated.
Explanation of symbols
1,21 Square member
3,23 flat member
5 Slit
7a, 7b, 7c, 13a, 13b, 27, 29, 41, 45, 85, 87, 173a, 173b
9,11 Adhesive
15, 35 Reinforcing material for connection
17, 37, 169a, 169b Adhesive surface
19,39 connecting part
25, 33 holes
47 Filler
53 Structure
55 Seismic isolation device
57, 57a, 57b layers
59 Basics
81 members
83,89 Protective reinforcement
99 Polyester belt
101, 171a, 171b Strip reinforcement
105,161 pillars
117 crack width
121 Tension
163 beams

Claims (53)

A method of reinforcing a structure in which a reinforcing material is installed on the outer peripheral surface of a plurality of adjacent members,
A reinforcing method of a structure, wherein a reinforcing material is passed through a space penetrating between a first member and another member which are close to each other or joined. 2. The method for reinforcing a structure according to claim 1, wherein the space is a gap between a first member and another member that are close to each other. 2. The method of reinforcing a structure according to claim 1, wherein the space is a slit or a hole provided in a joint portion between the joined first member and another member. 2. The method for reinforcing a structure according to claim 1, wherein the reinforcing material passed through the space is a sheet material having an adhesive surface at least at one end. 2. The method for reinforcing a structure according to claim 1, wherein the reinforcing material passed through the space is a belt-like material having adhesive surfaces at both ends. A reinforcing structure of a structure in which a reinforcing material is installed on the outer peripheral surface of a plurality of adjacent members,
A reinforcing structure for a structure, wherein a reinforcing material is passed through a space penetrating between a first member and another member that are close to each other or joined. The reinforcing structure for a structure according to claim 6, wherein the space is a gap between a first member and another member that are close to each other. The reinforcing structure for a structure according to claim 6, wherein the space is a slit or a hole provided in a joint portion between the joined first member and another member. The reinforcing structure for a structure according to claim 6, wherein the reinforcing material passed through the space is a sheet material provided with an adhesive surface at least at one end. The reinforcing structure for a structure according to claim 6, wherein the reinforcing material passed through the space is a band-shaped material having adhesive surfaces at both ends. A method of reinforcing a structure in which a reinforcing material is installed on the outer peripheral surface of a flat member,
A method for reinforcing a structure, characterized in that a band-shaped reinforcing material having adhesive surfaces at both ends is passed through a space penetrating a flat member. The method of reinforcing a structure according to claim 11, wherein the space is a hole. The method for reinforcing a structure according to claim 12, wherein the holes are provided in a lattice point shape. The method for reinforcing a structure according to claim 11, wherein the adhesive surface is provided perpendicular to an axial direction of the band-shaped reinforcing material. A reinforcing structure for a structure in which a reinforcing material is installed on the outer peripheral surface of a flat member,
A reinforcing structure for a structure, wherein a band-shaped reinforcing material having adhesive surfaces at both ends is passed through a space penetrating a flat member. 16. The structure reinforcing structure according to claim 15, wherein the space is a hole. The structure reinforcing structure according to claim 16, wherein the holes are provided in a lattice pattern. The reinforcing structure for a structure according to claim 15, wherein the adhesive surface is provided perpendicular to an axial direction of the belt-shaped reinforcing material. A method for reinforcing a structure, comprising: forming a sheet-like reinforcing material in a cylindrical shape on the outside of a member; and filling the inside of the reinforcing material with a granular filler. 20. The method of reinforcing a structure according to claim 19, wherein the reinforcing material is installed with a space between the members, and the space is filled with the filler of the granular material. The method of reinforcing a structure according to claim 19, wherein the reinforcing material is installed along an outer periphery of the member, and the inside of the member is filled with the filler of the granular material. A reinforcing structure for a structure in which a sheet-like reinforcing material is formed in a cylindrical shape on the outside of a member, and a granular filler is filled inside the reinforcing material. 23. The reinforcing structure for a structure according to claim 22, wherein the reinforcing material is installed with a space between the members, and the space is filled with the filler of the granular material. The reinforcing structure for a structure according to claim 22, wherein the reinforcing material is disposed along an outer periphery of the member, and the granular material is filled in the member. A seismic isolation device characterized in that a reinforcing material is installed around a granular filler, a concrete member, or a steel member. 26. The seismic isolation device according to claim 25, wherein a material that resists tension is disposed inside the granular filler, a concrete member, or a steel member. 26. The seismic isolation device according to claim 25, wherein the reinforcing material is an extensible sheet-like or strip-like material. 26. The seismic isolation device according to claim 25, wherein the horizontal section is circular. 26. The seismic isolation device according to claim 25, wherein a filler is mixed in the concrete member. A seismic isolation device according to any one of claims 25 to 29 is installed in a layer of a structure, between a foundation of a structure and a frame, or on the foundation of a structure. Reinforcement method. A structure, wherein the seismic isolation device according to any one of claims 25 to 29 is installed in a layer of the structure, between the foundation of the structure and the frame, or on the foundation of the structure. Reinforcement structure. A method of reinforcing a structure in which a reinforcing material is installed on the outer peripheral surface of a member,
A reinforcing method of a structure, wherein a plurality of reinforcing materials are installed in multiple on the outer peripheral surface of the member. The method of reinforcing a structure according to claim 32, wherein the plurality of reinforcing materials have different Young's moduli, and any one of them exhibits a reinforcing effect in accordance with a change in distortion of the member. The plurality of reinforcing materials are:
A first reinforcing material sharing the shearing force of the member;
A second reinforcement that restrains the apparent volume expansion of the member;
The method for reinforcing a structure according to claim 32, comprising: 35. The method for reinforcing a structure according to claim 33 or 34, wherein a reinforcing material that blocks action from the member and / or the outside world is further used as the plurality of reinforcing materials. A reinforcing structure of a structure in which a reinforcing material is installed on the outer peripheral surface of the member,
The reinforcing material is a reinforcing structure for a structure in which a plurality of reinforcing materials are installed in multiple. The reinforcing structure for a structure according to claim 36, wherein the plurality of reinforcing materials have different Young's moduli, and any one of them exhibits a reinforcing effect according to a change in strain of the member. The plurality of reinforcing materials are:
A first reinforcing material sharing the shearing force of the member;
A second reinforcement that restrains the apparent volume expansion of the member;
The reinforcing structure for a structure according to claim 36, comprising: The reinforcing structure for a structure according to claim 37 or 38, wherein a reinforcing material for blocking action from the member and / or the outside world is further installed as the plurality of reinforcing materials. A method for reinforcing a structure, comprising: bonding a band-shaped reinforcing material to an outer periphery of a member with an adhesive; and controlling the breakage by suppressing an increase in crack width of the member by the band-shaped reinforcing material. 41. The method for reinforcing a structure according to claim 40, wherein the band-shaped reinforcing material is installed in a multistage manner without gaps or at a predetermined interval in the member. 41. The method for reinforcing a structure according to claim 40, wherein the belt-shaped reinforcing material is a material having higher strength and rigidity than a civil engineering sheet. A reinforcing structure for a structure in which a band-shaped reinforcing material is bonded to an outer periphery of a member with an adhesive, and the band-shaped reinforcing material controls an increase in crack width of the member to control breakage. 44. The reinforcing structure for a structure according to claim 43, wherein the band-shaped reinforcing material is installed in the member in multiple stages without a gap or at a predetermined interval. The reinforcing structure for a structure according to claim 43, wherein the belt-shaped reinforcing material is a material having higher strength and rigidity than a civil engineering sheet. A method of reinforcing a structure that reinforces joints of a plurality of members,
Adhering an end portion of the sheet-like or belt-like reinforcing material to the side surface of the first member, adhering a portion continuing to the end portion to the side surface of the second member, and using the reinforcing material, A method for reinforcing a structure, comprising covering a joint portion with the second member. 47. The method for reinforcing a structure according to claim 46, wherein the other end of the reinforcing material is bonded to a side surface of a third member joined to the second member. It is a reinforcing structure for a structure that reinforces the joints of a plurality of members,
The end portion of the sheet-like or strip-like reinforcing material is bonded to the side surface of the first member, the portion continuing to the end portion is bonded to the side surface of the second member, and the first material and the A reinforcing structure for a structure, wherein a joint portion with the second member is covered. 49. The reinforcing structure for a structure according to claim 48, wherein the other end of the reinforcing member is bonded to a side surface of a third member joined to the second member. A reinforcing method for reinforcing a member having a joint,
A method of reinforcing a structure, wherein a band-shaped reinforcing material is spirally wound around the member above and below the joint, and the band-shaped reinforcing material is wound around the joint at the joint. A reinforcing structure for reinforcing a member having a joint,
A band-shaped reinforcing material is spirally wound around the member above and below the joint, and the band-shaped reinforcing material is wound around the joint at the joint. Reinforced structure. A reinforcing material obtained by impregnating a fiber material having impregnation property with a resin. 53. The reinforcing material according to claim 52, wherein the fibrous material is an extensible sheet-like or strip-like material.

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