JP3565957B2 - Bridge pier reinforcement method - Google Patents

Description

また、上記複合ポリマーエマルジョンが混合される主剤としては、具体的には砂とモルタルを主としており、以下の構成を有するものとしている。
【００２７】

なお、上記複合ポリマーエマルジョンと主剤との混合割合としては、１：３〜１０とするのが好ましい。
【００２８】
また、上記接着剤Ａは、防錆剤としても有効であり、そこで、本実施例では、鋼板からなる補強筒体２の表面に、かかる複合ポリマーエマルジョンを主剤に混合して製造した接着剤Ａを表面塗装剤として塗布して、鋼板からなる補強筒体２の腐食を確実に防止している。
【００２９】
なお、防錆効果を高めるために、主剤の成分中、酸化珪砂の一部または全部を腐食に強いセラミック粉に置換してもよい。さらに、本接着材Ａは、顔料とのなじみがよく着色自由であり、美観を高めるために、接着剤Ａ中に顔料を添加することも、また、接着材Ａの上から塗料を塗布することもできる。
【００３０】
このように、コンクリート製の橋脚本体１の周壁を、鋼板からなる補強筒体２で囲繞し、同橋脚本体１の周壁と補強筒体２との間の環状空間に、複合ポリマーエマルジョンを主剤に混合して製造した接着剤Ａを充填し、橋脚本体１に補強筒体２を一体的に接着して、橋脚１０に柔軟性と靱性とを付与し、大きな地震等により加わる力を受け流せる構造として、ひび割れから崩壊に至るまでを防止している。
【００３１】
また、本発明に係る接着剤は、カルボキシ変性スチレンブタジエン、メタクリル酸シクロヘキシル、メタノール、脂肪酸ソーダ石鹸、水を構成成分とする複合ポリマーエマルジョンを、白色セメント、珪砂、鉄粉、亜鉛華、チタン白を構成成分とする主剤に混合して製造しており、弾力性、接着性、防水性、防錆性に優れたものであり、コンクリートや鉄筋等の変形に追随でき、橋脚１０の耐震補強に好適に用いることができる。
【００３２】
（接着剤の一使用例）
ここでは、既存のコンクリート製の橋脚本体にコンクリート補強壁を接着剤を介して一体的に接着したコンクリート巻立構造としている。
【００３３】
すなわち、図３に示すように、既存のコンクリート製の橋脚本体１の周壁を、補強鉄筋４を埋設したコンクリート補強壁５で囲繞し、同コンクリート補強壁５を橋脚本体１の周壁に第一実施例で説明した接着剤Ａによって一体的に接着するとともに、補強鉄筋４の水平アンカー部４１と垂直アンカー部４２とを、橋脚本体１内に、前記接着剤Ａを介して打ち込んだ構成としたものである。
【００３４】
また、補強鉄筋４にも予め接着剤Ａを塗布してコンクリート補強壁５内に埋設したものとし、補強鉄筋４の腐食を防止するとともに、同補強鉄筋４とコンクリートとの付着性能を向上させ、かつ、引張耐力及び曲げ耐力を増強している。
【００３５】
また、水平アンカー部４１は橋脚本体１の脚部中途に水平方向に、垂直アンカー部４２は橋脚本体１の基礎部１ａに垂直方向へ、いずれも、接着剤Ａを介して打ち込んでいる。
【００３６】
接着剤Ａの強力な接着力により、両アンカー部４１，４２ はしっかりと固定されるのでコンクリート補強壁５は橋脚本体１に確実に一体化されて、しかも、接着剤Ａは弾力性を有するので、地震などによる大きな力を受けた場合に、コンクリートや鋼板の変形に追随することができ、橋脚１０に柔軟性と靱性を付与することができる。したがって、補強鉄筋４の量を格別に増加させることなく橋脚１０のひび割れや崩壊を防止できる。
【００３７】
本実施形態では、図４に示すように、コンクリート製の橋脚本体１の周壁を、複合ポリマーエマルジョンを主剤に混合して製造するとともに、内部に補強鉄筋６を埋設した補強ライニング層Ｂによって被覆した増厚補強構造としている。61は長尺の複数の主筋、62は同主筋61の長手方向に一定の間隔をあけて取付けた帯筋である。
【００３８】
前記補強ライニング層Ｂは、先に説明した接着剤Ａ中に補強鉄筋６を埋設したものである。すなわち、本実施の形態は、コンクリート製の橋脚本体１の周りの厚みが薄くなるように、型枠を組むことなく前記橋脚本体１の周壁を、複合ポリマーエマルジョンを主剤に混合して製造した接着剤Ａの内部に補強鉄筋６を埋設した補強ライニング層Ｂによって被覆し、しかも、前記補強鉄筋６を、複数の長尺の主筋61と、同主筋61に巻付けた螺旋状の帯筋62とから形成したことに特徴がある。なお、補強ライニング層Ｂ中に、炭素繊維、ガラス繊維、アラミド樹脂繊維等の補強繊維を混和させて強度を増大させることもできる。
【００３９】
本実施例は、前述したコンクリート巻立構造と異なり、型枠を組む必要がないので作業に手間が掛からず迅速に行え、しかも、橋脚本体１周りの厚みがはるかに薄く、死荷重増加が少なくなるとともに、基礎部1aのフーチング拡大がなく、当然ながら、拡大部に必要な増杭20も不要となるので、効率的な耐震補強となる。
【００４０】
図５(a)(b)に示した補強鉄筋６について説明する。
【００４１】
補強鉄筋６は、複数の長尺の主筋61と、同主筋61に巻付けた螺旋状の帯筋62とから形成したものであり、図５(a)は、これを円柱状の橋脚本体１に、図５(b)は角柱状の橋脚本体１に適用した場合を示している。
【００４２】
このように、帯筋62を螺旋状にしたものは、橋脚本体１が円柱状であっても、角柱状であっても補強鉄筋６の連続性が高まるので靱性が向上し、橋脚10自体を座屈や圧潰に対する強度を増すことができる。
【００５０】
【発明の効果】
以上説明してきたように、本発明では、コンクリート製の橋脚本体の周りの厚みが薄くなるように、型枠を組むことなく前記橋脚本体の周壁を、複合ポリマーエマルジョンを主剤に混合して製造した接着剤の内部に補強鉄筋を埋設した補強ライニング層によって被覆し、しかも、前記補強鉄筋を、複数の長尺の主筋と、同主筋に巻付けた螺旋状の帯筋とから形成しているので、橋脚に柔軟性、靱性を付与することができ、コンクリートの変形に追随することができる。例えば、橋脚に力が加わった場合、ある力までは弾性変形してひび割れ等を防止し、それ以上の大きな力が加われば塑性変形に移行するが、靱性が高いので耐力が一定値より下がらずに変形を大きく取ることができ、より大きな力を吸収することができ、橋脚の崩壊を防止することができる。
【００５１】
また、コンクリートの型枠を組む必要がないので施工性が向上するとともに、補強鉄筋の量が少なくても十分な耐震効果を得ることができる。しかも、形状による制約がない。
【００５２】
特に、上記補強鉄筋を、複数の長尺の主筋と、同主筋に巻付けた螺旋状の帯筋とから形成すれば、連続性が高まるので靱性が向上し、橋脚本体自体を座屈や圧潰に対する強度を増すことができる。
【図面の簡単な説明】
【図１】第１実施例に係る橋脚構造を示す説明図である。
【図２】本発明に係る橋脚構造の耐力を示すグラフである。
【図３】第２実施例に係る橋脚構造を示す説明図である。
【図４】第３実施例に係る橋脚構造を示す説明図である。
【図５】第４実施例に係る橋脚構造を示す説明図である。
【図６】第５実施例に係る橋脚構造を示す説明図である。
【符号の説明】
１ 橋脚本体
２ 補強筒体
４ 補強鉄筋
５ コンクリート補強壁
６ 補強鉄筋
６ａ 主筋
６ｂ 帯筋
１０ 橋脚
Ａ 接着剤[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for reinforcing a pier.
[0002]
[Prior art]
BACKGROUND ART Conventionally, there has been a concrete pier that has a reinforced steel plate or reinforced concrete integrated with a pier body to reinforce the pier, thereby enhancing the earthquake resistance.
[0003]
In such a structure, the peripheral wall of the pier main body is generally surrounded by a reinforcing steel plate or reinforced concrete, and the reinforced steel plate or the reinforced concrete is integrally bonded to the peripheral wall of the pier main body with a high-strength epoxy resin as an adhesive. .
[0004]
[Problems to be solved by the invention]
However, it was found that the conventional reinforcement described above did not provide sufficient earthquake resistance for concrete piers.
[0005]
This is considered to be due to a fundamental defect that the epoxy resin cannot follow the deformation of the concrete or the reinforcing steel plate when a large force is applied due to an earthquake or the like.
[0006]
Further, the epoxy resin has a property of being peeled off by water, which is a factor that hinders the integration of the pier body and the reinforcing material.
[0007]
Further, when the reinforcing material is concrete, it is necessary to assemble a formwork, so that it takes a long time, and during that time, there is a problem at the time of construction that the effect as an adhesive is weakened.
[0008]
In recent years, defects in the conventional pier structure pursuing only the strength described above have been pointed out, and it is urgently necessary to establish new seismic measures.
[0009]
Therefore, in order to impart flexibility and toughness to the pier so that the force can be passed, measures such as increasing the number of stirrups have been considered.
[0010]
However, if the eyes of the main reinforcing bar and the stirrup become too fine, there is a new problem that the aggregate may be caught halfway when the concrete is hit and a cavity may be formed below the aggregate.
[0011]
An object of the present invention is to provide a method for reinforcing a pier that can solve the above problems.
[0012]
[Means for Solving the Problems]
The present invention relates to a reinforcing steel reinforcing bar which is formed by mixing a peripheral wall of the pier main body with an adhesive prepared by mixing a composite polymer emulsion as a main component without forming a form so that a thickness around the concrete pier main body is reduced. A reinforcing lining layer in which the reinforcing steel is buried, and the reinforcing reinforcing bar is formed from a plurality of long main bars and a spiral band wound around the main bar. It is related.
[0018]
Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.
[0019]
(adhesive)
The pier structure according to the present embodiment has a steel plate winding structure in which a reinforcing tubular body made of a steel plate is integrally bonded to an existing concrete pier body.
[0020]
That is, in FIG. 1, reference numeral 10 denotes a pier. The pier 10 surrounds a peripheral wall of an existing pier main body 1 with a reinforcing cylinder 2 made of a steel plate, and a space between the peripheral wall of the pier main body 1 and the reinforcing cylinder 2. Is filled with an adhesive A, and a reinforcing tubular body 2 is integrally bonded to the pier body 1.
[0021]
The adhesive A is manufactured by mixing a composite polymer emulsion with a main component, has a strong adhesive force, and securely adheres a reinforcing tubular body 2 made of a steel plate to a concrete pier main body 1 to be integrated. Can be
[0022]
Moreover, since it has elasticity, it has the characteristic that it can follow the deformation of concrete or steel plate when subjected to a large force due to an earthquake or the like.
[0023]
Therefore, flexibility and toughness can be imparted to the pier 10. For example, when a force is applied to the pier 10, it is elastically deformed up to a certain force to prevent cracks and the like, and when a larger force is applied, the pier 10 becomes plastic. Although it shifts to deformation, since the toughness is high, as shown in FIG. 2, it is possible to take a large deformation without lowering the proof stress below a certain value, absorb a larger force, and prevent the pier 10 from collapsing. Can be prevented.
[0024]
Here, the adhesive A manufactured by mixing the composite polymer emulsion with the main component will be specifically described.
[0025]
The composite polymer emulsion includes, for example, those disclosed in JP-A-58-149961 and JP-A-60-2386503, and has the following components.
[0026]

In addition, the main agent to be mixed with the composite polymer emulsion is mainly sand and mortar, and has the following configuration.
[0027]

The mixing ratio between the composite polymer emulsion and the base is preferably 1: 3 to 10.
[0028]
Further, the adhesive A is also effective as a rust preventive. Therefore, in the present embodiment, the adhesive A produced by mixing the composite polymer emulsion with the main component on the surface of the reinforcing cylinder 2 made of a steel plate. Is applied as a surface coating agent to reliably prevent corrosion of the reinforcing cylinder 2 made of a steel plate.
[0029]
In order to enhance the rust prevention effect, part or all of the oxidized silica sand in the components of the main agent may be replaced with a ceramic powder resistant to corrosion. Furthermore, the present adhesive A has good compatibility with pigments and is free to be colored. In order to enhance aesthetic appearance, a pigment may be added to the adhesive A, or a paint may be applied on the adhesive A. You can also.
[0030]
In this manner, the peripheral wall of the concrete pier body 1 is surrounded by the reinforcing cylinder 2 made of a steel plate, and the annular polymer space between the peripheral wall of the pier main body 1 and the reinforcing cylinder 2 is mainly composed of the composite polymer emulsion. A structure in which the adhesive A manufactured by mixing is filled, and the reinforcing tubular body 2 is integrally bonded to the pier main body 1 to impart flexibility and toughness to the pier 10, and to be able to receive a force applied by a large earthquake or the like. To prevent from cracking to collapse.
[0031]
Further, the adhesive according to the present invention is a carboxy-modified styrene butadiene, cyclohexyl methacrylate, methanol, fatty acid soda soap, a composite polymer emulsion containing water as a component, white cement, silica sand, iron powder, zinc white, titanium white. Manufactured by mixing with the main component as a component, it is excellent in elasticity, adhesiveness, waterproofness, rust prevention, can follow deformation of concrete and reinforcing steel, etc., and is suitable for seismic reinforcement of pier 10. Can be used.
[0032]
(One use example of adhesive)
Here, a concrete wrapping structure in which a concrete reinforcing wall is integrally bonded to an existing concrete pier body via an adhesive is used.
[0033]
That is, as shown in FIG. 3, the surrounding wall of the existing concrete pier main body 1 is surrounded by the concrete reinforcing wall 5 in which the reinforcing steel bar 4 is embedded, and the concrete reinforcing wall 5 is firstly mounted on the peripheral wall of the pier main body 1. A structure in which the horizontal anchor portion 41 and the vertical anchor portion 42 of the reinforcing steel bar 4 are driven into the pier main body 1 via the adhesive A, while being integrally bonded by the adhesive A described in the example. It is.
[0034]
Further, it is assumed that the reinforcing agent 4 is coated with the adhesive A in advance and is buried in the concrete reinforcing wall 5 to prevent corrosion of the reinforcing bar 4 and to improve the adhesion performance between the reinforcing bar 4 and the concrete. In addition, the tensile strength and the bending strength are enhanced.
[0035]
The horizontal anchor portion 41 is driven in the middle of the leg portion of the pier main body 1 in the horizontal direction, and the vertical anchor portion 42 is driven in the vertical direction on the base portion 1a of the pier main body 1 via the adhesive A.
[0036]
Since the anchor portions 41 and 42 are firmly fixed by the strong adhesive force of the adhesive A, the concrete reinforcing wall 5 is surely integrated with the pier body 1, and the adhesive A has elasticity. When a large force due to an earthquake or the like is received, it is possible to follow the deformation of concrete or steel plate, and to impart flexibility and toughness to the pier 10. Therefore, it is possible to prevent the pier 10 from cracking or collapsing without particularly increasing the amount of the reinforcing bar 4.
[0037]
In the present embodiment, as shown in FIG. 4, the peripheral wall of the concrete pier main body 1 is manufactured by mixing a composite polymer emulsion with a main agent, and is covered with a reinforcing lining layer B in which a reinforcing steel bar 6 is embedded. It has a thickened reinforcement structure. Numeral 61 denotes a plurality of long main bars, and numeral 62 denotes a band bar attached at a predetermined interval in the longitudinal direction of the main bar 61.
[0038]
The reinforcing lining layer B is obtained by embedding the reinforcing bar 6 in the adhesive A described above. That is, in the present embodiment, the peripheral wall of the pier main body 1 is formed by mixing a composite polymer emulsion with a main agent without forming a form so that the thickness around the concrete pier main body 1 is reduced. A reinforcing lining layer B in which the reinforcing bar 6 is embedded inside the agent A, and the reinforcing bar 6 has a plurality of long main bars 61 and a spiral band 62 wound around the main bars 61. It is characterized by being formed from. In addition, the strength can also be increased by mixing reinforcing fibers such as carbon fiber, glass fiber, and aramid resin fiber into the reinforcing lining layer B.
[0039]
In this embodiment, unlike the above-described concrete wrapping structure, since it is not necessary to form a formwork, the work can be performed quickly without any trouble, and the thickness around the pier body 1 is much thinner, and the dead load increase is small. At the same time, there is no footing expansion of the foundation 1a, and naturally, the additional pile 20 required for the expansion is not required, so that efficient earthquake-resistant reinforcement is achieved.
[0040]
The reinforcing bar 6 shown in FIGS. 5A and 5B will be described.
[0041]
The reinforcing reinforcing bar 6 is formed of a plurality of long main bars 61 and a spiral band 62 wound around the main bar 61. FIG. FIG. 5B shows a case where the present invention is applied to a pier main body 1 having a prismatic shape.
[0042]
As described above, in the case where the stirrup 62 is formed in a spiral shape, the continuity of the reinforcing reinforcing bar 6 is enhanced even if the pier body 1 is cylindrical or prismatic, so that the toughness is improved, and the pier 10 itself is improved. Strength against buckling and crushing can be increased.
[0050]
【The invention's effect】
As described above, in the present invention, the peripheral wall of the pier main body is manufactured by mixing a composite polymer emulsion with a main component without forming a mold so that the thickness around the concrete pier main body is reduced. Since the reinforcing bar is covered with a reinforcing lining layer in which the reinforcing bar is embedded inside the adhesive, and the reinforcing bar is formed of a plurality of long main bars and a spiral band wound around the main bar. It can impart flexibility and toughness to the pier, and can follow the deformation of concrete. For example, when a force is applied to a bridge pier, it elastically deforms up to a certain force to prevent cracks, etc., and if a larger force is applied, it shifts to plastic deformation, but since the toughness is high, the proof strength does not fall below a certain value In this case, a large deformation can be taken, a larger force can be absorbed, and collapse of the pier can be prevented.
[0051]
In addition, since it is not necessary to form a concrete formwork, the workability is improved, and a sufficient seismic effect can be obtained even if the amount of reinforcing steel is small. Moreover, there is no restriction due to the shape.
[0052]
In particular, if the reinforcing reinforcing bar is formed from a plurality of long main bars and a spiral band wound around the main bar, continuity is enhanced, so that toughness is improved, and the pier body itself is buckled or crushed. Can be increased.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a pier structure according to a first embodiment.
FIG. 2 is a graph showing the proof stress of the pier structure according to the present invention.
FIG. 3 is an explanatory view showing a pier structure according to a second embodiment.
FIG. 4 is an explanatory view showing a pier structure according to a third embodiment.
FIG. 5 is an explanatory diagram showing a pier structure according to a fourth embodiment.
FIG. 6 is an explanatory view showing a pier structure according to a fifth embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Bridge pier main body 2 Reinforcement cylinder 4 Reinforcing bar 5 Reinforced concrete wall 6 Reinforcing bar 6a Main bar 6b Strip 10 Bridge pier A Adhesive

Claims (1)

An adhesive (A) manufactured by mixing the peripheral wall of the pier body (1) with a composite polymer emulsion as a main agent without forming a form so that the thickness around the concrete pier body (1) is reduced. covered with a reinforcing lining layer with embedded reinforcing rebar (6) inside the (B), moreover, winding the reinforcing rebar (6), and a plurality of elongate main reinforcement (61), in the main reinforcement (61) reinforcing method of piers and forming from the spiral hoop (62) has.

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