JPH0542924B2 - - Google Patents
Info
- Publication number
- JPH0542924B2 JPH0542924B2 JP63146839A JP14683988A JPH0542924B2 JP H0542924 B2 JPH0542924 B2 JP H0542924B2 JP 63146839 A JP63146839 A JP 63146839A JP 14683988 A JP14683988 A JP 14683988A JP H0542924 B2 JPH0542924 B2 JP H0542924B2
- Authority
- JP
- Japan
- Prior art keywords
- concrete
- rod
- shaped body
- precast concrete
- sheath
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000004567 concrete Substances 0.000 claims description 37
- 239000011178 precast concrete Substances 0.000 claims description 30
- 238000000034 method Methods 0.000 claims description 17
- 238000009415 formwork Methods 0.000 claims description 15
- 238000004519 manufacturing process Methods 0.000 claims description 13
- 239000000463 material Substances 0.000 claims description 4
- 229910001294 Reinforcing steel Inorganic materials 0.000 claims description 2
- 229910000831 Steel Inorganic materials 0.000 description 9
- 230000002787 reinforcement Effects 0.000 description 9
- 239000010959 steel Substances 0.000 description 9
- 239000011440 grout Substances 0.000 description 6
- 238000000465 moulding Methods 0.000 description 6
- 230000002093 peripheral effect Effects 0.000 description 3
- 230000003014 reinforcing effect Effects 0.000 description 3
- 239000004570 mortar (masonry) Substances 0.000 description 2
- 238000005452 bending Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012779 reinforcing material Substances 0.000 description 1
Landscapes
- Moulds, Cores, Or Mandrels (AREA)
- Manufacturing Of Tubular Articles Or Embedded Moulded Articles (AREA)
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は建設用柱、梁等のプレキヤストコンク
リート部材の製造方法に係るものである。DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for manufacturing precast concrete members such as construction columns and beams.
（従来の技術）
建造物のプレキヤストコンクリート柱の上下階
柱主筋の接合をシース筋方式によつて行なう場
合、プレキヤストコンクリート梁、壁の主筋用シ
ース部を形成する場合、或いはプレキヤストコン
クリート梁のプレストレスストランドまたは鋼棒
用等のシース部を形成する場合、従来は薄肉鋼製
シース管を所定位置に打込むことによつて、シー
ス部の成形を行なつていた。(Prior art) When connecting the main reinforcements of the upper and lower floors of precast concrete columns of a building using the sheath reinforcement method, when forming a sheath part for the main reinforcement of a precast concrete beam or wall, or when forming a sheath part for the main reinforcement of a precast concrete beam or a precast concrete beam When forming a sheath for a prestressed strand or steel rod, conventionally the sheath was formed by driving a thin-walled steel sheath tube into a predetermined position.
（発明が解決しようとする課題）
この場合、シース管が薄肉鋼製でパイプである
ため、プレキヤストコンクリート部材製作時のコ
ンクリート打設圧によつて、所定の位置からずれ
たり、撓んだり、或いは折れ曲つたりすることが
多く支障を招来することが多かつた。(Problems to be Solved by the Invention) In this case, since the sheath pipe is a pipe made of thin-walled steel, it may shift from a predetermined position or bend due to the concrete pouring pressure during the production of precast concrete members. Otherwise, they were often bent and twisted, often causing problems.
また、シース筋挿入後、グラウトモルタルを注
入するが、シース部のグラウトモルタルと部材コ
ンクリートとの境界は薄肉鋼製シース管によつて
絶縁されているため、シース内のグラウト材と部
材の本体コンクリートとの一体性が不十分で、構
造耐力上問題が多かつた。 In addition, after inserting the sheath reinforcement, grout mortar is injected, but since the boundary between the grout mortar in the sheath and the component concrete is insulated by a thin-walled steel sheath pipe, the grout in the sheath and the component concrete The integrity of the structure was insufficient, and there were many problems in terms of structural strength.
本発明はこのような従来技術の有する問題点に
鑑みて提案されたもので、その目的とする処は、
主筋、またはプレストレスストランド若しくは鋼
棒の配設用空洞部が部材の所定位置に精確に成形
され、且つ同空洞部に注入されるグラウト材と部
材コンクリートとの一体性が格段に向上される構
造耐力上有利なプレキヤストコンクリート部材の
製造方法を提供する点にある。 The present invention was proposed in view of the problems of the prior art, and its purpose is to:
A structure in which the cavity for arranging the main reinforcing bars, prestressed strands, or steel bars is precisely formed in the predetermined position of the member, and the integrity of the grout injected into the cavity and the concrete of the member is greatly improved. The object of the present invention is to provide a method for manufacturing a precast concrete member that is advantageous in terms of strength.
（課題を解決するための手段）
前記の目的を達成するため、本発明に係るプレ
キヤストコンクリート部材の製造方法は、プレキ
ヤストコンクリート部材製造用型枠内における補
強鋼材の配設位置に、外周面に螺旋状の溝、若し
くは突起を付した棒状体をセツトして前記型枠内
にコンクリートを打設し、同打設コンクリートが
未だ固化しない状態において、前記棒状体を回転
させながら引抜くように構成されている。(Means for Solving the Problems) In order to achieve the above-mentioned object, the method for manufacturing a precast concrete member according to the present invention provides a method for manufacturing a precast concrete member, in which the outer circumferential surface is A rod-shaped body with a spiral groove or a protrusion is set in the formwork, concrete is poured into the formwork, and the rod-shaped body is pulled out while rotating while the poured concrete has not yet solidified. It is configured.
なお前記の方法を遠心成形によつて行なう場合
は、型枠にコンクリートを充填して遠心成形した
直後、前記棒状体を回転させながら引抜くもので
ある。 In addition, when carrying out the said method by centrifugal molding, the said rod-shaped body is pulled out while rotating immediately after filling a mold with concrete and carrying out centrifugal molding.
また遠心成形によらず、型枠内にコンクリート
を打設するのみで前記の方法を行なう場合、打設
コンクリートの圧縮強度が5.0Kg／cm2程度以上に
なつたとき、前記棒状体を回転させながら引抜く
ものである。 In addition, when performing the above method by simply placing concrete in a formwork without using centrifugal forming, when the compressive strength of the poured concrete reaches approximately 5.0 kg/cm 2 or more, the rod-shaped body is rotated. It is something that you can pull out while doing so.
（作用）
本発明においては前記したように、プレキヤス
トコンクリート部材製造用型枠内における補強鋼
材の配置位置に、同補強鋼材を挿通するためのシ
ース部成形用型枠としての、外周面に螺旋状の
溝、若しくは突起を付した棒状体をセツトして、
前記プレキヤストコンクリート部材製造用型枠に
コンクリートを打設し、同打設コンクリートの未
固化状態のとき前記棒状体を回転させながら引抜
く。(Function) As described above, in the present invention, the sheath part molding formwork for inserting the reinforcing steel material into the formwork for producing precast concrete members is provided with a spiral on the outer circumferential surface. A rod-shaped body with a shaped groove or a protrusion is set,
Concrete is poured into the formwork for producing precast concrete members, and when the poured concrete is in an unsolidified state, the rod-shaped body is pulled out while rotating.
この結果、内側表面に前記棒状体の螺旋状の溝
または突起によつて、連続した螺旋状の突起また
は溝を有する所要のシース部の空洞部が成形され
る。 As a result, a required cavity of the sheath portion having a continuous spiral protrusion or groove is formed on the inner surface by the helical groove or protrusion of the rod-shaped body.
前記の方法を遠心成形法によつて行なう場合、
打設コンクリートが遠心力によつて圧密させるた
め、前記棒状体の回転させながらの引抜きを遠心
成形の直後行つても、シース部の空洞が十分に保
形される。 When the above method is carried out by centrifugal molding,
Since the poured concrete is consolidated by centrifugal force, the shape of the cavity of the sheath portion is sufficiently maintained even if the rod-shaped body is pulled out while rotating immediately after centrifugal forming.
遠心成形を行なうことなく、型枠内にコンクリ
ートを打設するのみで前記の方法を行なう場合、
打設コンクリートの圧縮強度が５Kg／cm2程度以上
になつたとき、前記棒状体を回転させながら引抜
くことによつて、プレキヤストコンクリート部材
中に内側表面に連続した螺旋状の突起、または溝
を有するシース部の空洞が成形される。 If the above method is carried out by simply placing concrete in the formwork without performing centrifugal forming,
When the compressive strength of the poured concrete reaches approximately 5 kg/cm 2 or more, continuous spiral protrusions or grooves are formed on the inner surface of the precast concrete member by rotating and pulling out the bar. A cavity of the sheath portion having a diameter is formed.
（実施例） 以下本発明を図示の実施例について説明する。(Example) The present invention will be described below with reference to the illustrated embodiments.
第１図及び第２図に示すように、プレキヤスト
コンクリート柱部材製造用型枠１における柱主筋
挿通用シース部に、鋼管や鋼棒等の、コンクリー
ト打設圧により撓曲したり折れ曲らないような十
分の強度を有する円形断面部材の外周面に等ピツ
チの連続した螺旋状の突起３を付した棒状体２を
セツトする。 As shown in Figs. 1 and 2, steel pipes, steel bars, etc., are bent or bent due to concrete placement pressure in the sheath portion for inserting the column main reinforcement in the formwork 1 for manufacturing precast concrete column members. A rod-shaped body 2 having continuous spiral protrusions 3 of equal pitch on the outer circumferential surface of a circular cross-sectional member having sufficient strength such that the rod-shaped body 2 has sufficient strength such that the rod-shaped body 2 has a circular cross-section is set.
このとき、前記棒状体２の位置がずれないよう
に、端部が前記型枠に固定される。 At this time, the ends of the rod-like bodies 2 are fixed to the formwork so that the rod-shaped bodies 2 do not shift.
次いでフープ筋４等、必要な鉄筋の配筋を行な
つたのち、コンクリート５を充填し、遠心成形を
行なつた直後、前記棒状体２を回転しながら引き
抜く。棒状体２の回転数と引抜き長さとの関係
は、引抜き長さに相当する螺旋の巻き数と等しい
回転数でなければならない。 Next, after arranging necessary reinforcing bars such as hoop reinforcements 4, concrete 5 is filled, and immediately after centrifugal forming, the rod-shaped body 2 is pulled out while rotating. The relationship between the number of rotations of the rod-shaped body 2 and the length of the rod-shaped member 2 must be equal to the number of turns of the spiral corresponding to the length of the rod-shaped member 2.
この結果、プレキヤストコンクリート柱部材の
所定位置に、内周面に前記螺旋状突起２の断面形
状を有する連続した螺旋状の溝が形成されたシー
ス部を容易に成形することができる。 As a result, a sheath portion having a continuous helical groove having the cross-sectional shape of the helical protrusion 2 formed on the inner circumferential surface can be easily formed at a predetermined position of the precast concrete column member.
なお遠心成形の場合は、打設コンクリート５に
遠心力が加わり圧密されているため、シース部成
形用の棒状体２の回転させながらの引抜作業を遠
心成形の直後に行なつても、シース部の空洞を保
形することができる。またこの時期に前記棒状体
２を回転させながら引き抜く場合は、打設コンク
リート５と同棒状体２との付着力が低く、同棒状
体２の回転させながらの引き抜きが容易に行なわ
れる。 In the case of centrifugal forming, since centrifugal force is applied to the poured concrete 5 and it is consolidated, even if the drawing operation while rotating the rod-shaped body 2 for forming the sheath part is performed immediately after centrifugal forming, the sheath part It is possible to retain the shape of the cavity. Further, when the rod-shaped body 2 is pulled out while rotating at this time, the adhesion force between the cast concrete 5 and the rod-shaped body 2 is low, and the rod-shaped body 2 can be easily pulled out while being rotated.
また遠心成形によらず、前記型枠内にコンクリ
ートを打設する場合には、打設コンクリートの圧
縮強度が５Kg／cm2以上になつたとき、前記棒状体
２を回転させながら引抜くことによつて、プレキ
ヤストコンクリート柱部材内に内側面に螺旋状の
溝が形成された中空シース部を成形するものであ
る。 In addition, when concrete is poured into the formwork without using centrifugal forming, when the compressive strength of the poured concrete reaches 5 kg/cm 2 or more, the rod-shaped body 2 is pulled out while rotating. Therefore, a hollow sheath portion having a spiral groove formed on the inner surface is formed in the precast concrete column member.
なお第３図に示すように、棒状体２の外周面に
連続した等ピツチの螺旋状溝３を設けてもよく、
この場合、プレキヤストコンクリート柱部材の所
定位置に内周面に連続した螺旋状の突起が形成さ
れたシース部が成形される。 In addition, as shown in FIG. 3, continuous spiral grooves 3 of equal pitch may be provided on the outer peripheral surface of the rod-shaped body 2.
In this case, a sheath portion in which a continuous spiral protrusion is formed on the inner circumferential surface is formed at a predetermined position of the precast concrete column member.
なお前記実施例はプレキヤストコンクリート柱
部材の主筋用シース部の成形に本発明の方法を適
用した場合を示したものであるが、本発明はこの
他、プレキヤストコンクリート梁部材のプレスト
レスストランド、また鋼棒用シース部、梁主筋用
シース部の成形、プレキヤストコンクリート壁の
壁主筋用シース部の成形に適用される。 Although the above-mentioned example shows the case where the method of the present invention is applied to forming the main reinforcing sheath part of a precast concrete column member, the present invention also applies to prestress strands of a precast concrete beam member, It is also applied to forming sheath parts for steel bars, sheath parts for beam main reinforcements, and sheath parts for wall main reinforcements in precast concrete walls.
（発明の効果）
本発明によれば前記したように、プレキヤスト
コンクリート部材製造用型枠における補強材の配
設位置に、従来のように薄肉鋼管製シース管をセ
ツトすることなく、外周面に螺旋状の溝若しくは
突起を付した棒状体をセツトしてコンクリートを
打設し、同打設コンクリートが未固化状態のうち
に、前記棒状体を回転させながら引抜くことによ
つて、内周面に連続した螺旋状の突起または溝を
有するシース部を成形をするようにしたので、前
記棒状体を十分な強度を有する部材より構成する
ことができ、コンクリート打設圧や、セツト時に
受ける外圧等によつて撓曲したり、折れ曲つたり
することがない。(Effects of the Invention) According to the present invention, as described above, a sheath pipe made of thin-walled steel pipe is not set at the position of reinforcing material in a formwork for producing precast concrete members, as is the case with the conventional method, but can be applied to the outer peripheral surface. A rod-shaped body with spiral grooves or protrusions is set and concrete is poured, and the inner circumferential surface is removed by rotating and pulling out the rod-shaped body while the poured concrete is still unsolidified. Since the sheath part having a continuous spiral protrusion or groove is molded, the rod-shaped body can be made of a material with sufficient strength, and can withstand concrete placement pressure, external pressure applied during setting, etc. It will not bend or bend due to bending.
またシース部空洞がプレキヤストコンクリート
部材本体のコンクリートによつて形成されている
ため、グラウト材と本体コンクリートとが直接接
触することになり、両者の付着性能が増大し、構
造耐力の向上が図られる。 In addition, since the sheath cavity is formed by the concrete of the precast concrete member body, the grout material and the body concrete come into direct contact, increasing the adhesion performance of both and improving structural strength. .
更にプレキヤストコンクリート部材中に成形さ
れるシース部内周面に形成される螺旋状の溝の断
面形状を、従来のシース管の場合に比して大きな
断面とすることができ、更にまた前記シース部の
螺旋状の溝または突起のピツチを細かくしたり、
粗くしたり、自由に設計でき、従つて従来のシー
ス管方式に比してプレキヤストコンクリート部材
のコンクリートとグラウト材との一体性が格段に
向上し、構造耐力上有利である
更にまた本発明によれば、前記棒状体を回転さ
せながら引抜くことによつて、同棒状体の引抜き
作業が容易に行なわれる。 Furthermore, the cross-sectional shape of the spiral groove formed on the inner peripheral surface of the sheath part formed in the precast concrete member can be made larger than that of a conventional sheath pipe, and furthermore, the sheath part by making the pitch of the spiral grooves or protrusions finer,
It can be roughened or designed freely, and therefore, the integrity of the concrete and grout of the precast concrete member is significantly improved compared to the conventional sheath pipe method, which is advantageous in terms of structural strength.Furthermore, the present invention According to this, by pulling out the rod-shaped body while rotating it, the pulling out operation of the rod-shaped body is easily performed.
請求項２の発明は、前記の方法を遠心成形によ
つて行なう場合、型枠内コンクリートが遠心力に
よつて圧密され、前記棒状体を回転しながら引き
抜いてもシース部空洞を十分に保形できるので、
前記棒状体の引抜きを遠心成形の直後に行なうよ
うにしたもので、しかもこの時期、打設コンクリ
ートと棒状体との付着力も低く同棒状体の引抜き
が容易に行なわれることと相俟つて、製造能率を
向上しうるものである。 The invention according to claim 2 provides that when the above method is carried out by centrifugal molding, the concrete in the form is consolidated by centrifugal force, and the sheath cavity can sufficiently retain its shape even if the rod-shaped body is pulled out while rotating. Because you can
The rod-shaped body is pulled out immediately after centrifugal forming, and the adhesion between the cast concrete and the rod-shaped body is low at this time, making it easy to pull out the rod-shaped body. This can improve manufacturing efficiency.
請求項３の発明の前記の方法を遠心成形によら
ず、型枠内にコンクリートを打設するのみで行な
う場合、打設コンクリートの圧縮強度が5.0Kg／
cm2程度以上になつたとき、前記棒状体を回転させ
ながら打設コンクリートより引き抜き、製造能率
を向上しうるものである。 When the method of the invention of claim 3 is carried out by simply pouring concrete into a form without using centrifugal molding, the compressive strength of the poured concrete is 5.0 kg/
When it reaches about cm 2 or more, the rod-shaped body is pulled out from the poured concrete while rotating, thereby improving manufacturing efficiency.
第１図は本発明に係るプレキヤストコンクリー
ト部材の製造方法の一実施例の実施状況を示す横
断平面図、第２図及び第３図は夫々棒状体の平面
図である。
１……プレキヤストコンクリート柱部材製造用
型枠、２……棒状体、２ａ……螺旋状突起、２ｂ
……螺旋状溝、５……コンクリート。
FIG. 1 is a cross-sectional plan view showing an embodiment of the method for manufacturing a precast concrete member according to the present invention, and FIGS. 2 and 3 are plan views of a rod-shaped body, respectively. 1... Formwork for manufacturing precast concrete column members, 2... Rod-shaped body, 2a... Spiral projection, 2b
...Spiral groove, 5...Concrete.
Claims (1)
における補強鋼材の配設位置に、外周面に螺旋状
の溝若しくは突起を付した棒状体をセツトして前
記型枠内にコンクリートを打設し、同打設コンク
リートが未だ固化しない状態において、前記棒状
体を回転させながら引抜くことを特徴とするプレ
キヤストコンクリート部材の製造方法。 ２ 前記部材を遠心成形する場合、型枠にコンク
リートを充填して遠心成形した直後、前記棒状体
を回転させながら引抜く請求項１記載のプレキヤ
ストコンクリート部材の製造方法。 ３ 遠心成形によらず、型枠内にコンクリートを
打設するのみで前記部材を成形する場合、打設コ
ンクリートの圧縮強度が5.0Kg／cm2程度以上にな
つたとき、前記棒状体を回転させながら引抜く請
求項１記載のプレキヤストコンクリート部材の製
造方法。[Claims] 1. A rod-shaped body with a spiral groove or protrusion on its outer circumferential surface is set at the position where the reinforcing steel material is placed in a formwork for producing precast concrete members, and concrete is poured into the formwork. A method for manufacturing a precast concrete member, which comprises placing the rod-shaped body in a state where the cast concrete has not yet hardened, and then pulling out the rod-shaped body while rotating it. 2. The method for manufacturing a precast concrete member according to claim 1, wherein when the member is centrifugally formed, the rod-shaped body is pulled out while being rotated immediately after filling a mold with concrete and centrifugally forming the member. 3. When forming the above-mentioned member by simply placing concrete in a formwork without using centrifugal forming, when the compressive strength of the poured concrete reaches approximately 5.0 kg/ cm2 or more, the rod-shaped body may be rotated. 2. The method for manufacturing a precast concrete member according to claim 1, wherein the precast concrete member is pulled out while being pulled out.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14683988A JPH01316217A (en) | 1988-06-16 | 1988-06-16 | Manufacture of precast concrete member |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14683988A JPH01316217A (en) | 1988-06-16 | 1988-06-16 | Manufacture of precast concrete member |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01316217A JPH01316217A (en) | 1989-12-21 |
| JPH0542924B2 true JPH0542924B2 (en) | 1993-06-30 |
Family
ID=15416696
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP14683988A Granted JPH01316217A (en) | 1988-06-16 | 1988-06-16 | Manufacture of precast concrete member |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01316217A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008069519A (en) * | 2006-09-12 | 2008-03-27 | Ohbayashi Corp | Precast concrete member, and manufacturing method therefor |
| JP2017193168A (en) * | 2016-04-18 | 2017-10-26 | 大成建設株式会社 | Hollow frame device for pc, pc bar-shaped material, building material for column made of concrete and method for producing the same |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5228124A (en) * | 1975-07-03 | 1977-03-02 | Bernardi Dario | Awning type blind |
-
1988
- 1988-06-16 JP JP14683988A patent/JPH01316217A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5228124A (en) * | 1975-07-03 | 1977-03-02 | Bernardi Dario | Awning type blind |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008069519A (en) * | 2006-09-12 | 2008-03-27 | Ohbayashi Corp | Precast concrete member, and manufacturing method therefor |
| JP2017193168A (en) * | 2016-04-18 | 2017-10-26 | 大成建設株式会社 | Hollow frame device for pc, pc bar-shaped material, building material for column made of concrete and method for producing the same |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01316217A (en) | 1989-12-21 |
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