JPH07159259A - Method and apparatus for detecting effective stress of concrete - Google Patents

Method and apparatus for detecting effective stress of concrete

Info

Publication number
JPH07159259A
JPH07159259A JP31148593A JP31148593A JPH07159259A JP H07159259 A JPH07159259 A JP H07159259A JP 31148593 A JP31148593 A JP 31148593A JP 31148593 A JP31148593 A JP 31148593A JP H07159259 A JPH07159259 A JP H07159259A
Authority
JP
Japan
Prior art keywords
concrete
case
load cell
adhesive
face
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP31148593A
Other languages
Japanese (ja)
Other versions
JP2643081B2 (en
Inventor
Tadahiko Natsume
忠彦 夏目
Yasuo Murayama
八洲雄 村山
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kajima Corp
Original Assignee
Kajima Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kajima Corp filed Critical Kajima Corp
Priority to JP31148593A priority Critical patent/JP2643081B2/en
Publication of JPH07159259A publication Critical patent/JPH07159259A/en
Application granted granted Critical
Publication of JP2643081B2 publication Critical patent/JP2643081B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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  • Force Measurement Appropriate To Specific Purposes (AREA)
  • Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)

Abstract

PURPOSE:To provide a method and apparatus for detecting the effective stress of concrete in which the stress can be read out directly with high accuracy. CONSTITUTION:The case side pressure-sensitive end face 13a of a load cell 13 and the case side coupling end face 12a of a coupler 12 are coated with an adhesive 16 exhibiting the bonding strength higher than the expected tensile strength of concrete at a rate higher than the hardening rate of concrete while being in contact with moisture. The load cell 13 is fitted in the opening at one end of a tubular case body 11 having opposite open ends for insulating the inner concrete from the outside in the sense of stress and allowing movement of moisture with respect to the outside whereas the coupler 12 is fitted in the opening on the opposite side. The case body 11 is filed, at the intermediate part thereof, with concrete of identical quality and age to a concrete being measured thus forming a concrete column 15 bonded to the case side pressure- sensitive end face 13a of the load cell 13 and the case side coupling end face 12a of the coupler 12. The case body 11 is then placed in a mass of concrete 30 to be measured and the effective stress is detected based on the output from the load cell 13.

Description

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

【0001】[0001]

【産業上の利用分野】本発明は、コンクリートの有効応
力検出方法及び装置に関し、とくにコンクリート塊内の
有効応力を高精度で直読できるコンクリートの有効応力
検出方法及び装置に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for detecting effective stress in concrete, and more particularly to a method and apparatus for detecting effective stress in concrete which can directly read the effective stress in a concrete block with high accuracy.

【0002】[0002]

【従来の技術】コンクリートの有効応力を直読するた
め、本発明者は被測定コンクリートを入れる細長いケー
ス体とその一端に取付けたロードセルからなるコンクリ
ートの有効応力検出装置を開発し、これを特公昭58ー
1736号公報に開示した。本発明の理解に必要な限度
においてこのコンクリートの有効応力検出装置を図3に
より簡単に説明する。一端に連結体12、他端にロードセ
ル13をそれぞれ結合したコンクリート柱体15を細長い筒
状ケース体11内に形成してコンクリートの有効応力検出
装置1とする。連結体12及びロードセル13に取付けた付
着体14をコンクリート柱体15に埋め込み、被測定コンク
リートと連結体12及びロードセル13との結合を確実にす
る。筒状ケース体11は、その内外間の水分の移動を許容
するが内部のコンクリート柱体15を外部から応力的に絶
縁する。使用に当たっては図1(C)に示すように、この
コンクリートの有効応力検出装置1を被測定コンクリー
トのコンクリート塊30に埋め込み、ロードセル13の出力
をリード線34を介して適当な表示器35に表示させる。た
だし、コンクリートの有効応力検出装置1内のコンクリ
ート柱15のコンクリートは被測定コンクリートと同質・
同材令とする。図3(C)の記号17は、コンクリート柱体
15形成用の生コンクリート注入口に対する蓋を示す。
2. Description of the Related Art In order to directly read the effective stress of concrete, the present inventor has developed an effective stress detecting device for concrete, which comprises an elongated case body containing the concrete to be measured and a load cell attached to one end thereof. -1736. This effective stress detecting device for concrete will be briefly described with reference to FIG. 3 within a limit necessary for understanding the present invention. A concrete column body 15 in which a connecting body 12 is connected to one end and a load cell 13 is connected to the other end is formed in an elongated cylindrical case body 11 to form an effective concrete stress detecting device 1. The attachment body (14) attached to the connecting body (12) and the load cell (13) is embedded in the concrete column body (15) to ensure the coupling between the concrete to be measured and the connecting body (12) and the load cell (13). The cylindrical case body 11 allows the movement of water between the inside and the outside thereof, but insulates the internal concrete column body 15 from the outside by stress. In use, as shown in FIG. 1 (C), the concrete effective stress detecting device 1 is embedded in the concrete block 30 of the concrete to be measured, and the output of the load cell 13 is displayed on an appropriate indicator 35 via the lead wire 34. Let However, the concrete of the concrete column 15 in the concrete effective stress detection device 1 has the same quality as the concrete to be measured.
Same age. Symbol 17 in FIG. 3 (C) is a concrete column
15 shows a lid for a ready-mixed concrete injection port.

【0003】図3のコンクリートの有効応力検出装置1
の弾性係数Emと被測定コンクリートの弾性係数Ecとの
比(測定精度と呼ぶことがある。)Kは次式で与えられ
る。
A concrete effective stress detecting device 1 shown in FIG.
The ratio K of the elastic coefficient Em of the elastic modulus Em to the elastic coefficient Ec of the concrete to be measured (sometimes called measurement accuracy) K is given by the following equation.

【0004】[0004]

【数1】 K=Ec/Em=(β/n)・(Ls/L)+(Lc/L) ……(1) ここに、 Ec:被測定コンクリートのコンクリート塊30の弾性係
数(kgf/cm2) Em:有効応力検出装置1の弾性係数(kgf/cm2) β=Ac/As Ac:コンクリート柱15の断面積(cm2) As:ロードセル13の断面積(cm2) n=Es/Ec Es:ロードセル13の鋼材の弾性係数(kgf/cm2) Ls:ロードセル13の見かけ長さ(cm)(図3参照) Lc:コンクリート柱15の見かけ長さ(cm)(図3参
照)、ただしLcはLsに比し十分大きいものとする L:有効応力検出装置1の見かけ長さ(cm)、ただしL=
Ls+Lc
[Equation 1] K = Ec / Em = (β / n) · (Ls / L) + (Lc / L) (1) where, Ec: elastic modulus of the concrete block 30 of the concrete to be measured (kgf / cm 2 ) Em: Elastic modulus of effective stress detector 1 (kgf / cm 2 ) β = Ac / As Ac: Cross-sectional area of concrete column 15 (cm 2 ) As: Cross-sectional area of load cell 13 (cm 2 ) n = Es / Ec Es: Elastic modulus of steel material of load cell 13 (kgf / cm 2 ) Ls: Apparent length of load cell 13 (cm) (see Fig. 3) Lc: Apparent length of concrete column 15 (cm) (see Fig. 3) , Where Lc is sufficiently larger than Ls L: Apparent length (cm) of the effective stress detection device 1, where L =
Ls + Lc

【0005】本発明者は、(1)式で与えられる比Kが被
測定コンクリートの弾性係数Ecの広範囲にわたって一
定に近いので、有効応力検出装置1による有効応力度検
出はロードセル13の荷重検出のみによって行えるとの知
見を得、被測定コンクリートの有効応力度はロードセル
13の検出荷重をケース体11内のコンクリート柱15の断面
積Acで除せば求められることを見出した。よって、被
測定コンクリートの有効応力度検出が非常に簡単にな
り、若材令のコンクリートに対しても正確な有効応力度
検出が可能になり、引張り応力にも追随可能となり、有
効応力検出装置の設置が容易になった。
Since the ratio K given by the equation (1) is close to constant over a wide range of the elastic modulus Ec of the concrete to be measured, the inventor of the present invention can detect the effective stress level by the effective stress detecting device 1 only by detecting the load of the load cell 13. The effective stress of the concrete to be measured is the load cell.
It has been found that the detected load of 13 is obtained by dividing by the cross-sectional area Ac of the concrete column 15 in the case body 11. Therefore, it becomes very easy to detect the effective stress level of the concrete to be measured, and it becomes possible to detect the effective stress level accurately even for the young concrete, and it is possible to follow the tensile stress. Easy to install.

【0006】[0006]

【発明が解決しようとする課題】図3のコンクリート有
効応力検出装置1は、付着体14のために測定精度が低く
なる欠点を有する。その理由を説明するに、測定精度を
表わす上記比Kに対する上記(1)式は次のように書き直
せる。
The concrete effective stress detecting device 1 of FIG. 3 has a drawback that the measuring accuracy becomes low due to the adhered body 14. To explain the reason, the above equation (1) for the ratio K representing the measurement accuracy can be rewritten as follows.

【0007】[0007]

【数2】 K=(β/n)・(Ls/L)+(Lc/L) =(β/n)・(Ls/L)+{(L−Ls)/L} =1−(Ls/L)+(β/n)・(Ls/L) =1−(Ls/L){1+(β/n)} ……(2)## EQU00002 ## K = (. Beta./n).multidot.(Ls/L)+(Lc/L)=(.beta./n).multidot.(Ls/L)+{(L-Ls)/L}=1-(Ls / L) + (β / n) · (Ls / L) = 1- (Ls / L) {1+ (β / n)} (2)

【0008】被測定コンクリートの有効応力度をロード
セル13の検出荷重とコンクリート柱15の断面積Acとの
比として求める場合には、上記比Kが1.0の時に最高の
測定精度が得られるが、(2)式は付着体14の長さを含む
ロードセル13の見かけ長さLsの増大即ち(Ls/L)の
増大に伴い精度が低下することを示す。
When the effective stress of the concrete to be measured is determined as the ratio of the detected load of the load cell 13 and the cross-sectional area Ac of the concrete column 15, the highest measurement accuracy can be obtained when the ratio K is 1.0. Equation (2) shows that the accuracy decreases as the apparent length Ls of the load cell 13 including the length of the adherend 14 increases, that is, (Ls / L) increases.

【0009】また、付着体14は金属製であるが、コンク
リート柱15の両端に剛性の高い付着体14が存在する場合
には、コンクリート柱15内の応力状態が乱れ測定精度低
下の原因となる。さらにケース体11内へコンクリートを
充填する際に、付着体14が障害物となりケース体11内の
コンクリート分布が不均一となり著しい場合には空隙発
生を招く虞があり、測定精度低下の原因となる。
Further, although the adhering body 14 is made of metal, if the adhering body 14 having high rigidity is present at both ends of the concrete pillar 15, the stress state in the concrete pillar 15 is disturbed and causes a decrease in measurement accuracy. . Further, when the case body 11 is filled with concrete, the adhering body 14 becomes an obstacle and the concrete distribution in the case body 11 becomes non-uniform and may cause voids in the case where it becomes significant, which causes a decrease in measurement accuracy. .

【0010】従って、本発明の目的は測定精度が高く直
読が可能なコンクリートの有効応力検出方法及び装置を
提供するにある。
Therefore, an object of the present invention is to provide a method and an apparatus for detecting an effective stress of concrete which has high measurement accuracy and can be directly read.

【0011】[0011]

【課題を解決するための手段】本発明者は、生の被測定
コンクリートとの接触下において前記コンクリートの予
想引張り強度より大きな接着強度を前記コンクリートの
硬化速度より高速で発現する如き接着剤を予めロードセ
ル及び連結体のコンクリート接着面に付着させた後、ロ
ードセルのコンクリート接着面と連結体のコンクリート
接着面との間に生の被測定コンクリートを充填するなら
ば、被測定コンクリートが硬化した時にロードセル及び
連結体と強固に結合したコンクリート柱を形成すると同
時に、測定精度に貢献するロードセルの見かけ長さLs
を著しく短くすることができることに着目した。上記接
着剤による結合を用いるならば、(2)式のLsにおいて
付着体14の長さを除くことができるので、右辺第2項の
(Ls/L)を縮小し測定精度を向上させる手法により
本発明を完成した。
Means for Solving the Problems The present inventor has previously developed an adhesive that develops an adhesive strength larger than the expected tensile strength of the concrete at a higher speed than the hardening rate of the concrete under contact with the raw concrete to be measured. If the raw measured concrete is filled between the concrete adhesive surface of the load cell and the concrete adhesive surface of the connection body after adhering to the concrete adhesive surface of the load cell and the connection body, when the measured concrete hardens, the load cell and The apparent length Ls of the load cell that contributes to the measurement accuracy at the same time as forming a concrete column that is firmly connected to the connecting body
We focused on the fact that can be significantly shortened. If the bonding by the above adhesive is used, the length of the adherent 14 can be excluded from Ls in the equation (2), so that the second term on the right side (Ls / L) can be reduced to improve the measurement accuracy. The present invention has been completed.

【0012】図1を参照するに、本発明によるコンクリ
ートの有効応力検出方法は、生の被測定コンクリートと
の接触下において前記コンクリートの予想引張り強度よ
り大きな接着強度を前記コンクリートの硬化速度より高
速で発現する如き接着剤16をロードセル13及び連結体12
のコンクリート接着面に付着させ、両端の間に充填空間
を形成し且つ外部と水分移動を許すと共に前記充填空間
に充填されるコンクリートを外部から応力的に絶縁する
両端開放の細長い筒状ケース体11の一端開口に前記ロー
ドセル13のコンクリート接着面を嵌入し、前記ケース体
11の他端開口に前記連結体12のコンクリート接着面を嵌
入し、前記ケース体11の充填空間に被測定コンクリート
と同質・同材令の生コンクリートを充填して前記ロード
セル13及び連結体12と前記接着剤16で結合したコンクリ
ート柱体15を形成するようにし、充填後の前記ケース体
11を被測定コンクリート塊30の中に設置し前記ロードセ
ル13の出力により被測定コンクリートの有効応力を検出
する。図1の実施例においては、接着剤16が、ロードセ
ル13のケース側感圧端面13a及び連結体12のケース側連
結端面12aに付着され、ケース体11中のケース側感圧端
面13aとケース側連結端面12aとの間が前記充填空間とな
っている。ケース体11の内外間の水分移動を許すには、
ケース体11の周囲壁にコンクリートは通さないが水分を
通すような細孔を設けてもよく、ケース体11の充填空間
に充填されるコンクリートを外部から応力的に絶縁する
には、ケース体11の周囲壁の内側に適当な縁切材(図示
せず)を設けてもよい。
Referring to FIG. 1, the method for detecting the effective stress of concrete according to the present invention provides an adhesive strength, which is larger than the expected tensile strength of the concrete under the contact with the raw concrete to be measured, at a higher speed than the hardening rate of the concrete. The adhesive 16 as expressed is applied to the load cell 13 and the connecting body 12.
An elongated cylindrical case body 11 with both ends opened, which is adhered to the concrete adhesive surface of the concrete, forms a filling space between both ends, allows moisture to move to the outside, and insulates the concrete filled in the filling space from the outside by stress. Insert the concrete adhesion surface of the load cell 13 into one end opening of the case body,
Insert the concrete adhesive surface of the connecting body 12 into the other end opening of 11, and fill the filling space of the case body 11 with fresh concrete of the same quality and age as the measured concrete and the load cell 13 and the connecting body 12. The case body after being filled is formed so as to form the concrete pillar body 15 bonded with the adhesive 16.
11 is installed in the measured concrete block 30, and the effective stress of the measured concrete is detected by the output of the load cell 13. In the embodiment of FIG. 1, the adhesive 16 is attached to the case-side pressure-sensitive end surface 13a of the load cell 13 and the case-side connecting end surface 12a of the connecting body 12, and the case-side pressure-sensitive end surface 13a and the case-side in the case body 11 are attached. The space between the connecting end surface 12a is the filling space. To allow water movement between the inside and outside of the case body 11,
The peripheral wall of the case body 11 may be provided with pores that allow moisture to pass through, but the concrete filled in the filling space of the case body 11 may be stress-insulated from the outside by the case body 11. A suitable edging material (not shown) may be provided inside the peripheral wall of the.

【0013】本発明によるコンクリートの有効応力検出
装置1は、両端間に充填空間を形成し且つ外部と水分移
動を許すと共に前記充填空間に充填されるコンクリート
を外部から応力的に絶縁する両端開放の細長い筒状ケー
ス体11;前記ケース体11の一端の開放口に嵌入して該開
放口を閉塞するケース側感圧端面13aを有するロードセ
ル13であって、前記ケース側感圧端面13aに、生コンク
リートとの接触下において該生コンクリートの硬化後の
予想引張り強度より大きな接着強度を前記コンクリート
の硬化速度より高速で発現する如き接着剤16を付着した
ロードセル13;及び前記ケース体11の他端開放口に嵌入
して該開放口を閉塞するケース側連結端面12aを有する
連結体12であって、前記ケース側連結端面12aに前記接
着剤16を付着した連結体12を備えてなるものである。好
ましくは、ロードセル13の前記ケース側感圧端面13a及
び/又は連結体12のケース側連結端面12aを粗面とし、
接着剤16とロードセル13及び/又は連結体12との結合を
強固にする。
The concrete effective stress detecting device 1 according to the present invention has an open end for forming a filling space between both ends of the concrete, allowing moisture to move to the outside, and insulating the concrete filled in the filling space from the outside by stress. An elongated cylindrical case body 11; a load cell 13 having a case-side pressure-sensitive end surface 13a which is fitted into an opening opening at one end of the case body 11 and closes the opening opening, the raw-cell load cell 13 being formed on the case-side pressure-sensitive end surface 13a. A load cell 13 to which an adhesive 16 is attached so as to develop an adhesive strength greater than the expected tensile strength after hardening of the green concrete under contact with concrete at a higher speed than the hardening speed of the concrete; and the other end of the case body 11 is opened. A coupling body (12) having a case-side coupling end surface (12a) fitted into a mouth and closing the opening, the coupling body (12) having the adhesive agent (16) attached to the case-side coupling end surface (12a). It become one. Preferably, the case-side pressure-sensitive end surface 13a of the load cell 13 and / or the case-side connecting end surface 12a of the connecting body 12 is a rough surface,
The bond between the adhesive 16 and the load cell 13 and / or the connecting body 12 is strengthened.

【0014】図2(A)を参照するに、接着剤16との結合
を強化するため、好ましくは、ロードセル13のケース側
感圧端面13a及び連結体12のケース側連結端面12aの少な
くとも一方をサンドブラスト加工等により微細な凹凸の
ある粗面とする。同様な目的のため、例えばロードセル
13のケース側感圧端面13aを図2(B)のような溝切り加
工による微細凹凸面18とするか、又は図2(C)のような
切削若しくは鍛造による波形面19としてもよい。連結体
12のケース側連結端面12aを上記微細凹凸面18又は波形
面19とすることもできる。
Referring to FIG. 2A, in order to strengthen the connection with the adhesive 16, at least one of the case-side pressure-sensitive end surface 13a of the load cell 13 and the case-side connecting end surface 12a of the connecting body 12 is preferably used. A rough surface with fine irregularities is made by sandblasting. For similar purposes, eg load cell
The case-side pressure-sensitive end surface 13a of 13 may be a fine concavo-convex surface 18 formed by grooving as shown in FIG. 2B, or may be a corrugated surface 19 formed by cutting or forging as shown in FIG. 2C. Connected body
The case-side connecting end surface 12a of 12 may be the fine concavo-convex surface 18 or the corrugated surface 19.

【0015】[0015]

【作用】本発明方法により被測定コンクリートのコンク
リート柱15を図1のように形成した有効応力検出方法装
置1においては、ロードセル13及び連結体12とコンクリ
ート柱15との間の結合を有効応力度検出に必要な強さに
すると同時に、ロードセルの見かけ長さLsを著しく短
くできるので、(2)式の右辺第2項の(Ls/L)を縮
小し、被測定コンクリートの弾性係数Ecと有効応力検
出装置1の弾性係数Emとの比Kを1.0に近づけ、測定精
度を向上させることができる。なお、連結体12の見かけ
長さLp(図3)も短縮され、この短縮が結果的にコン
クリート柱15の見かけ長さLc、従って有効応力検出装
置1の見かけ長さL(=Ls+Lc)を増大させ、(2)式
の右辺第2項の(Ls/L)の縮小により測定精度の向
上に貢献する。さらに、図3の付着体14を全く用いない
ので、付着体14によるコンクリート柱15内の応力状態の
乱れ及びケース体11内へのコンクリート充填時の障害を
未然に防止し測定精度を向上させることができる。
In the apparatus 1 for detecting the effective stress in which the concrete columns 15 of the concrete to be measured are formed by the method of the present invention as shown in FIG. 1, the connection between the load cell 13 and the connecting body 12 and the concrete columns 15 is measured by the effective stress level. Since the apparent length Ls of the load cell can be significantly shortened at the same time as the strength required for detection, (Ls / L) of the second term on the right side of the equation (2) is reduced to be effective with the elastic modulus Ec of the measured concrete. The ratio K with the elastic coefficient Em of the stress detection device 1 can be brought close to 1.0 to improve the measurement accuracy. The apparent length Lp (FIG. 3) of the connecting body 12 is also shortened, and this shortening results in an increase in the apparent length Lc of the concrete column 15, and thus the apparent length L (= Ls + Lc) of the effective stress detecting device 1. Then, the reduction of (Ls / L) of the second term on the right side of the equation (2) contributes to the improvement of the measurement accuracy. Furthermore, since the adhesive body 14 of FIG. 3 is not used at all, it is possible to prevent the disturbance of the stress state in the concrete column 15 due to the adhesive body 14 and the obstacle at the time of filling the concrete in the case body 11 to improve the measurement accuracy. You can

【0016】しかも、有効応力検出装置1のロードセル
13の検出荷重に対し、これをコンクリート柱15の断面積
Acで除する簡単な演算処理を加えることにより、被測
定コンクリートの応力度を直読することが可能である。
Moreover, the load cell of the effective stress detector 1
It is possible to directly read the stress level of the concrete to be measured by adding a simple calculation process to the detected load of 13 by dividing it by the cross-sectional area Ac of the concrete column 15.

【0017】こうして、本発明の目的である「測定精度
が高く直読が可能なコンクリートの有効応力検出方法及
び装置」の提供が達成される。
Thus, the object of the present invention is to provide a "method and apparatus for detecting effective stress in concrete which has high measurement accuracy and can be directly read".

【0018】[0018]

【実施例】上記接着強度及び接着強度発現速度を有する
接着剤16として、コンクリートの打継ぎ面の接着に用い
る二液混合型のエポキシ系接着剤を使い、(1)式におけ
る(Ls/L)を0.100とした図1(A)の構造の有効応力
検出装置1を試作した。他の条件を図1(A)と同一にし
(Ls/L)を0.300とした従来構造のものと上記本発明
の試作品との間で、測定精度Kを(1)式による計算で比
較した結果を表1に示す。
[Example] As the adhesive 16 having the above-mentioned adhesive strength and adhesive strength developing speed, a two-liquid mixed type epoxy adhesive used for adhering the joint surface of concrete is used, and (Ls / L) in the formula (1) is used. The effective stress detecting device 1 having the structure of FIG. The measurement accuracy K was compared by the calculation by the formula (1) between the conventional structure in which (Ls / L) was 0.300 and the other conditions were the same as those in FIG. 1A and the prototype of the present invention. The results are shown in Table 1.

【0019】[0019]

【表1】 測定精度Kの(1)式による計算値 装置の (Ls/L) Ecの値 (×106kgf/cm2)* 平均 種別 の値 0.01 0.1 0.2 0.3 0.5 従来例 0.300 K=0.71 0.77 0.83 0.90 1.04 0.85 本発明 0.100 K=0.90 0.92 0.95 0.97 1.01 0.97* Ec:被測定コンクリートの弾性係数[Table 1] Measurement accuracy K calculated by equation (1) (Ls / L) Ec value of equipment (× 10 6 kgf / cm 2 ) * Average type value 0.01 0.1 0.2 0.3 0.5 Conventional example 0.300 K = 0.71 0.77 0.83 0.90 1.04 0.85 The present invention 0.100 K = 0.90 0.92 0.95 0.97 1.01 0.97 * Ec: Elastic modulus of measured concrete

【0020】表1に示すように、本発明は従来例に比し
被測定コンクリートの弾性係数Ecの変化に対する測定
精度の変動が少く、且つ平均の測定精度が10%以上向上
している。
As shown in Table 1, according to the present invention, the fluctuation of the measurement accuracy with respect to the change of the elastic modulus Ec of the concrete to be measured is smaller than that of the conventional example, and the average measurement accuracy is improved by 10% or more.

【0021】なおロードセル13として、図1(B)に示す
ように外側受圧面となるフランジ20を有するものを用い
た。図中Ltはケース体11の長さを示し、Lpは連結体12
のケース体11への埋め込み深さを示す。
As the load cell 13, a load cell having a flange 20 serving as an outer pressure receiving surface as shown in FIG. 1 (B) was used. In the figure, Lt indicates the length of the case body 11, and Lp indicates the connecting body 12.
The depth of embedding in the case body 11 is shown.

【0022】この有効応力検出装置1の測定精度較正方
法の一例を図1(C)に示す。有効応力検出装置1を被測
定コンクリート塊30中に埋め込み、変位計31を取付枠32
で取付けた後、荷重試験機33で荷重を加えつつ、ロード
セル13の検出荷重をリード線34を介して表示器35に加え
れば、有効応力を有効応力検出装置1の出力として測定
できる。この測定値を、荷重試験機33の荷重及びコンク
リート塊30の断面積から求めた有効応力と比較すれば、
有効応力検出装置1の測定精度を較正できる。このとき
のコンクリート塊30の弾性係数は変位計31の出力及び荷
重試験機33の荷重とを用いて確認できる。
An example of a method for calibrating the measurement accuracy of the effective stress detecting device 1 is shown in FIG. 1 (C). The effective stress detector 1 is embedded in the concrete block 30 to be measured, and the displacement gauge 31 is attached to the mounting frame 32.
After mounting with the load tester 33, the effective stress can be measured as the output of the effective stress detecting device 1 by applying the detected load of the load cell 13 to the indicator 35 through the lead wire 34 while applying the load with the load tester 33. If this measured value is compared with the load of the load tester 33 and the effective stress obtained from the cross-sectional area of the concrete mass 30,
The measurement accuracy of the effective stress detection device 1 can be calibrated. The elastic modulus of the concrete block 30 at this time can be confirmed using the output of the displacement meter 31 and the load of the load tester 33.

【0023】以上の説明においてコンクリートの有効応
力として引張り及び圧縮の両者を想定したが、検出すべ
き有効応力が圧縮応力のみである場合には、接着剤16の
使用を省略できる。
In the above description, both tensile and compression are assumed as the effective stress of concrete, but when the effective stress to be detected is only the compressive stress, the use of the adhesive 16 can be omitted.

【0024】[0024]

【発明の効果】以上詳細に説明したように本発明のコン
クリートの有効応力検出方法及び装置は、水分との接触
下で大きな接着強度を発現する接着剤によりロードセル
と被測定コンクリートとを結合するので、次の顕著な効
果を奏する。
As described in detail above, the method and apparatus for detecting the effective stress of concrete of the present invention combine the load cell and the concrete to be measured with an adhesive that exhibits a large adhesive strength under the contact with moisture. , Has the following remarkable effects.

【0025】(イ)有効応力検出装置のコンクリート柱
における応力の乱れが全く無くなり、応力分布を安定さ
せて測定精度を向上させることができる。 (ロ)有効応力検出装置のケース体へのコンクリート充
填が容易になり且つ均一な充填ができ、作業性の向上及
びコンクリート柱の空隙防止による測定精度向上を図る
ことができる。 (ハ)有効応力検出装置の見かけ長さとロードセルの見
かけ長さとの比(Ls/L)を小さくし、測定精度を改
善することができる。
(B) The disturbance of the stress in the concrete column of the effective stress detector is completely eliminated, and the stress distribution can be stabilized and the measurement accuracy can be improved. (B) It is possible to easily and uniformly fill the case body of the effective stress detection device with concrete, and it is possible to improve workability and improve measurement accuracy by preventing voids in concrete columns. (C) The ratio (Ls / L) between the apparent length of the effective stress detector and the apparent length of the load cell can be reduced to improve the measurement accuracy.

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

【図1】は、本発明の一実施例の説明図である。FIG. 1 is an explanatory diagram of an embodiment of the present invention.

【図2】は、接着剤による接着面の説明図である。FIG. 2 is an explanatory diagram of a bonding surface with an adhesive.

【図3】は、従来技術の説明図である。FIG. 3 is an explanatory diagram of a conventional technique.

【符号の説明】[Explanation of symbols]

1 有効応力検出装置 11 ケース体
12 連結体 12a ケース側連結端面 13 ロードセル
13a ケース側感圧端面 14 付着体 15 コンクリート柱体
16 接着剤 17 蓋 18 微細凹凸面
19 波形面 20 フランジ 30 コンクリート塊
31 変位計 32 取付枠 33 荷重試験機
34 リード線 35 表示器。
1 Effective stress detector 11 Case body
12 Connection body 12a Case side connection end face 13 Load cell
13a Case side pressure-sensitive end surface 14 Adhesive body 15 Concrete column
16 Adhesive 17 Lid 18 Fine uneven surface
19 Corrugated surface 20 Flange 30 Concrete block
31 Displacement meter 32 Mounting frame 33 Load tester
34 Lead wire 35 Indicator.

Claims (5)

【特許請求の範囲】[Claims] 【請求項1】生の被測定コンクリートとの接触下におい
て前記コンクリートの予想引張り強度より大きな接着強
度を前記コンクリートの硬化速度より高速で発現する如
き接着剤をロードセル及び連結体のコンクリート接着面
に付着させ;両端の間に充填空間を形成し且つ外部と水
分移動を許すと共に前記充填空間に充填されるコンクリ
ートを外部から応力的に絶縁する両端開放の細長い筒状
ケース体の一端開口に前記ロードセルのコンクリート接
着面を嵌入し、前記ケース体の他端開口に前記連結体の
コンクリート接着面を嵌入し;前記ケース体の充填空間
に被測定コンクリートと同質・同材令の生コンクリート
を充填して前記ロードセル及び連結体と前記接着剤で結
合したコンクリート柱体を形成するようにし;充填後の
前記ケース体を被測定コンクリート塊の中に設置し前記
ロードセルの出力により被測定コンクリートの有効応力
を検出する方法。
1. An adhesive which adheres to a concrete adhesion surface of a load cell and a connection body so as to develop an adhesive strength larger than an expected tensile strength of the concrete at a higher speed than a hardening rate of the concrete under contact with raw concrete to be measured. A loading space is formed between both ends of the load cell at one end opening of a long and narrow cylindrical case body that allows moisture to move from the outside and allows the concrete filling in the filling space to be stress-insulated from the outside. Insert the concrete adhesive surface, insert the concrete adhesive surface of the connection body into the other end opening of the case body; fill the filling space of the case body with fresh concrete of the same quality and age as the measured concrete, and A concrete pillar is formed by connecting the load cell and the connecting body with the adhesive, and the case body after filling is covered. Method for detecting the effective stress of the measured concrete by installed output of the load cell in a constant concrete mass.
【請求項2】両端の間に充填空間を形成し且つ外部と水
分移動を許すと共に前記充填空間に充填されるコンクリ
ートを外部から応力的に絶縁する両端開放の細長い筒状
ケース体;前記ケース体の一端の開放口に嵌入して該開
放口を閉塞するケース側感圧端面を有するロードセルで
あって、前記ケース側感圧端面に、生コンクリートとの
接触下において該生コンクリートの硬化後の予想引張り
強度より大きな接着強度を前記コンクリートの硬化速度
より高速で発現する如き接着剤を付着したロードセル;
及び前記ケース体の他端開放口に嵌入して該開放口を閉
塞するケース側連結端面を有する連結体であって、前記
ケース側連結端面に前記接着剤を付着した連結体を備え
てなるコンクリートの有効応力検出装置。
2. An elongated tubular case body having open ends, which forms a filling space between both ends thereof, allows moisture to move to the outside, and insulates the concrete filled in the filling space from the outside by stress. Is a load cell having a case-side pressure-sensitive end surface that fits into an open port at one end of the load port and closes the open port, wherein the case-side pressure-sensitive end face is expected to be after hardening of the raw concrete under contact with the fresh concrete. A load cell to which an adhesive is attached so as to develop an adhesive strength larger than the tensile strength at a higher speed than the hardening rate of the concrete;
And a connecting body having a case-side connecting end surface that is fitted into the other end opening of the case body to close the opening, the concrete comprising a connecting body having the adhesive attached to the case-side connecting end surface. Effective stress detector.
【請求項3】請求項2の有効応力検出装置において、前
記ケース側感圧端面及びケース側連結端面の少なくとも
一方を粗面としてなるコンクリートの有効応力検出装
置。
3. The effective stress detecting device according to claim 2, wherein at least one of the case-side pressure-sensitive end face and the case-side connecting end face is a rough surface.
【請求項4】請求項2の有効応力検出装置において、前
記ケース側感圧端面及びケース側連結端面の少なくとも
一方を微細凹凸面としてなるコンクリートの有効応力検
出装置。
4. The concrete effective stress detecting device according to claim 2, wherein at least one of the case-side pressure-sensitive end face and the case-side connecting end face is a fine uneven surface.
【請求項5】請求項2の有効応力検出装置において、前
記ケース側感圧端面及びケース側連結端面の少なくとも
一方を波形面としてなるコンクリートの有効応力検出装
置。
5. The effective stress detecting device according to claim 2, wherein at least one of the case-side pressure-sensitive end face and the case-side connecting end face has a corrugated surface.
JP31148593A 1993-12-13 1993-12-13 Method and apparatus for detecting effective stress of concrete Expired - Fee Related JP2643081B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP31148593A JP2643081B2 (en) 1993-12-13 1993-12-13 Method and apparatus for detecting effective stress of concrete

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP31148593A JP2643081B2 (en) 1993-12-13 1993-12-13 Method and apparatus for detecting effective stress of concrete

Publications (2)

Publication Number Publication Date
JPH07159259A true JPH07159259A (en) 1995-06-23
JP2643081B2 JP2643081B2 (en) 1997-08-20

Family

ID=18017805

Family Applications (1)

Application Number Title Priority Date Filing Date
JP31148593A Expired - Fee Related JP2643081B2 (en) 1993-12-13 1993-12-13 Method and apparatus for detecting effective stress of concrete

Country Status (1)

Country Link
JP (1) JP2643081B2 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102323157A (en) * 2011-07-27 2012-01-18 大连理工大学 Concrete multi-shaft tension compression stress combination testing method
JP2012229982A (en) * 2011-04-26 2012-11-22 Toyo Constr Co Ltd Method and apparatus for health monitoring of concrete structure
CN103712858A (en) * 2014-01-01 2014-04-09 浙江建设职业技术学院 Spiral type loading positioning device for column
CN104251801A (en) * 2014-09-12 2014-12-31 上海建工集团股份有限公司 Test device for measuring lateral pressure of concrete template
CN106323522A (en) * 2016-08-12 2017-01-11 中国科学院东北地理与农业生态研究所 Device for measuring pull-down force of root of rod-shaped plant, and application method of device
CN114894362A (en) * 2022-05-11 2022-08-12 中国水利水电科学研究院 Method and device for measuring stress of cylinder column force measurement type concrete structure in whole process

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012229982A (en) * 2011-04-26 2012-11-22 Toyo Constr Co Ltd Method and apparatus for health monitoring of concrete structure
CN102323157A (en) * 2011-07-27 2012-01-18 大连理工大学 Concrete multi-shaft tension compression stress combination testing method
CN103712858A (en) * 2014-01-01 2014-04-09 浙江建设职业技术学院 Spiral type loading positioning device for column
CN104251801A (en) * 2014-09-12 2014-12-31 上海建工集团股份有限公司 Test device for measuring lateral pressure of concrete template
CN106323522A (en) * 2016-08-12 2017-01-11 中国科学院东北地理与农业生态研究所 Device for measuring pull-down force of root of rod-shaped plant, and application method of device
CN114894362A (en) * 2022-05-11 2022-08-12 中国水利水电科学研究院 Method and device for measuring stress of cylinder column force measurement type concrete structure in whole process

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