JPH02276965A - Method for measuring water cement ratio of fresh concrete - Google Patents
Method for measuring water cement ratio of fresh concreteInfo
- Publication number
- JPH02276965A JPH02276965A JP9805689A JP9805689A JPH02276965A JP H02276965 A JPH02276965 A JP H02276965A JP 9805689 A JP9805689 A JP 9805689A JP 9805689 A JP9805689 A JP 9805689A JP H02276965 A JPH02276965 A JP H02276965A
- Authority
- JP
- Japan
- Prior art keywords
- mortar
- cement
- water
- cement ratio
- fresh concrete
- 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.)
- Pending
Links
- 239000004568 cement Substances 0.000 title claims abstract description 35
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 15
- 238000000034 method Methods 0.000 title claims description 5
- 239000004570 mortar (masonry) Substances 0.000 claims abstract description 31
- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 claims abstract description 7
- 239000000706 filtrate Substances 0.000 claims abstract description 5
- 239000003456 ion exchange resin Substances 0.000 claims abstract description 5
- 229920003303 ion-exchange polymer Polymers 0.000 claims abstract description 5
- 238000001035 drying Methods 0.000 claims abstract description 4
- 238000003756 stirring Methods 0.000 abstract description 5
- 238000005259 measurement Methods 0.000 abstract description 4
- 230000002378 acidificating effect Effects 0.000 abstract description 2
- 239000003729 cation exchange resin Substances 0.000 abstract description 2
- 238000012216 screening Methods 0.000 abstract description 2
- 238000004090 dissolution Methods 0.000 abstract 1
- 208000020442 loss of weight Diseases 0.000 abstract 1
- 239000000203 mixture Substances 0.000 abstract 1
- 239000011398 Portland cement Substances 0.000 description 2
- 238000012937 correction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000010998 test method Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 229920001467 poly(styrenesulfonates) Polymers 0.000 description 1
- 238000003908 quality control method Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Landscapes
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
Description
【発明の詳細な説明】
〈産業上の利用分野〉
本発明は、フレッシュコンクリート内の水セメント比の
測定方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for measuring the water-cement ratio in fresh concrete.
〈従来の技術〉
コンクリートの強度は単位セメント量、および水セメン
ト比に依存している。<Prior art> The strength of concrete depends on the unit amount of cement and the water-cement ratio.
そこでフレッシュコンクリートの品質管理が重要になる
が、特に打設現場で打設前に迅速に水セメント比を判断
して品質を把握することが大切である。Therefore, quality control of fresh concrete is important, and it is especially important to quickly determine the water-cement ratio and understand the quality before pouring at the pouring site.
〈本発明の目的〉・
本発明はこうしたコンクリートの強度に大きく影響する
、フレッシュコンクリートの水セメント比を、コンクリ
ートの打設現場において簡単に測定する方法を提供する
ことを目的とする。<Object of the present invention> The present invention aims to provide a method for easily measuring the water-cement ratio of fresh concrete, which greatly affects the strength of concrete, at a concrete placement site.
〈本発明の構成〉 次に本発明の実施例について説明する。<Configuration of the present invention> Next, examples of the present invention will be described.
〈イ〉使用材料
（１）セメント
フレッシュコンクリートに使用する材料として、普通ポ
ルトランドセメントを使用した。<A> Materials used (1) Cement Ordinary Portland cement was used as the material for fresh concrete.
普通ポルトランドセメントを使用したコンクリートを、
フレッシュコンクリートとして採取した。Concrete using ordinary portland cement,
It was collected as fresh concrete.
（２）イオン交換樹脂
イオン交換樹脂としてはダウケミカル社製の、ダウエッ
クス５０ＷＸ４（２００〜４００メツシユ）のＨ型強酸
性陽イオン交換樹脂（以下１ｔ−Ｒ）を使用した。(2) Ion Exchange Resin As the ion exchange resin, DOWEX 50WX4 (200 to 400 mesh) H-type strongly acidic cation exchange resin (hereinafter referred to as 1t-R) manufactured by Dow Chemical Company was used.
く口〉試験方法
〈電気伝導度の測定〉
（１）フレッシュコンクリート約２ リットルを、５ｍ
ｍのふるいでウェットスクリーニングし、モルタルを得
る。Test method〈Measurement of electrical conductivity〉 (1) Approximately 2 liters of fresh concrete is poured into a 5 m
Wet screen with a sieve of 500 ml to obtain mortar.
（２）モルタルを１リツトルビーカーに入れ、十分に撹
拌する。(2) Place the mortar in a 1 liter beaker and stir thoroughly.
モルタルより天秤を用いて２．ＯＯｇ （小数点以下第
２位まで測定）採取し、１００ｍ１ビーカーに入れる。2. Using a scale from mortar. Collect OOg (measured to two decimal places) and place in a 100ml beaker.
（３）続いてホールピペットで蒸留純水を５０ｍ１加え
、次いであらかじめ蒸留純水で十分水洗し、減圧ろ過し
たＨ−Ｒ２０ｇ を入れ、１５分間、時々撹拌しながら
静置する。(3) Next, add 50 ml of distilled pure water using a whole pipette, then add 20 g of H-R that has been thoroughly washed with distilled pure water and filtered under reduced pressure, and let stand for 15 minutes with occasional stirring.
（４）撹拌終了後に、ろ紙を二枚重ねてこれをろ過し、
ろ液の電気伝導度（以下 ｋ という）を測定する。(4) After the stirring is finished, filter this using two layers of filter paper,
Measure the electrical conductivity (hereinafter referred to as k) of the filtrate.
電気伝導度の測定には次のような装置を使用した。The following device was used to measure electrical conductivity.
装 置−東亜電波製 ＣＭ−６０５電気伝導度
セル二束亜電波製 ＣＧ−５１１Ｂ〈モルタル量の測定
〉
（１）別にフレッシュコンクリートから、５ｍｍのふる
いでウェットスクリーニングし、モルタルを得る。Apparatus - CM-605 electrical conductivity cell manufactured by Toa Denpa; CG-511B manufactured by Adenpa (Measurement of amount of mortar) (1) Separately, fresh concrete is wet screened with a 5 mm sieve to obtain mortar.
このモルタルを天秤を使って２０．’ＯＯｇ （小数点
以下第２位まで測定）採取し、２００ｍ１ビーカーに入
れる。20. Use this mortar with a balance. Collect 'OOg (measured to two decimal places) and put it in a 200ml beaker.
（２）このモルタルをガスバーナーまたは空気浴で１５
分間乾燥する。(2) Heat this mortar with a gas burner or air bath for 15 minutes.
Let dry for a minute.
（３）乾燥した後、天秤でモルタルの質量（Ｍ）を測定
する。(3) After drying, measure the mass (M) of the mortar using a balance.
〈ハ〉試験結果
（１）セメント量の測定
上記の試験方法で得た ｋ の測定値を第１図に図示す
る。<C> Test results (1) Measurement of cement amount The measured values of k obtained by the above test method are illustrated in Figure 1.
図においてＹ軸をに、Ｘ軸を計画水セメント比としてシ
己入する。In the figure, the Y-axis is entered as the planned water-cement ratio, and the X-axis is entered as the planned water-cement ratio.
すると両者の関係は、次式で表される。Then, the relationship between the two is expressed by the following equation.
Ｙ−０，０６５＋３−．２９３Ｘ−・・・・（１）こう
してモルタル２ｇ 中のセメント量（Ｂ）を決定する
。Y-0,065+3-. 293X- (1) Thus, determine the amount of cement (B) in 2 g of mortar.
（２）水セメント量の計算
上記の方法によってモルタルの質ｆｆｌ（Ｍ）が測定し
である。(2) Calculating the amount of water cement The quality of mortar ffl(M) is determined by the above method.
したがって、水セメント比は次式で与えられる。Therefore, the water-cement ratio is given by:
Ｗ／Ｃ−（Ａ−ｑ Ｘ Ｃ）／Ｂ Ｘ １００−１０−
−−４２）Ｃ＝［２−（Ａ＋８）］／［１−（ｑ／１０
０）］ここにＣ：モルタル２ｇ中の細骨材の質量（ｇ）
Ａ＝（２０−Ｍ）／１０：モルタル２ｇ中の水量（ｇ）
Ｂ：モルタル２ｇ中のセメント量（ｇ）ｑ：細骨材の吸
水率（％）
〈ニ〉考察
補正なしにＷ／Ｃを測定すると、計画水セメント比より
１０％高い値となる。W/C-(A-q X C)/B X 100-10-
--42) C=[2-(A+8)]/[1-(q/10
0)] where C: Mass of fine aggregate in 2g of mortar (g)
A=(20-M)/10: Amount of water (g) in 2g of mortar
B: Amount of cement in 2 g of mortar (g) q: Water absorption rate of fine aggregate (%) <d> If W/C is measured without consideration and correction, it will be a value 10% higher than the planned water-cement ratio.
この原因はウェットスクリーニングしたことによりモル
タルの水量が多（なり、粗骨材に付着したセメントより
モルタルのＷ／Ｃの方が高くなったからと考えられる。The reason for this is thought to be that the amount of water in the mortar was large due to wet screening, and the W/C of the mortar was higher than that of the cement attached to the coarse aggregate.
そこで式（２）に示すように補正項（−１０）を付けて
計算した。Therefore, the calculation was performed by adding a correction term (-10) as shown in equation (2).
その結果を推定水セメント比と計画水セメント比の関係
として表すと第２図に示すようになる。The results are expressed as the relationship between the estimated water-cement ratio and the planned water-cement ratio as shown in Figure 2.
両者の関係は±３ネの範囲内で一致している。The relationship between the two is consistent within the range of ±3.
またＷ／Ｃ＝６０％の付近では、フレッシュコンクリー
トが軟らかいためにばらつきが見られる。Also, around W/C=60%, variations are seen because the fresh concrete is soft.
そこで同一試料からモルタルを３回採取して判定試験を
行うと、水セメント比が±１〜３％の範囲内で判定する
ことが可能である。Therefore, if mortar is sampled three times from the same sample and a determination test is performed, it is possible to determine the water-cement ratio within the range of ±1 to 3%.
以上の考察から、水セメント比は、第１図から測定した
ｋ の測定値、および水量によって定量が可能である
ことが分かる。From the above considerations, it can be seen that the water-cement ratio can be quantified using the measured value of k measured from FIG. 1 and the amount of water.
の判定を迅速に行うことができる。can be quickly determined.
第１図：電気伝導度とモルタル２ｇ中のセメント比との
関係を表す図
第２図：推定水セメント比と計画水セメント比の関係を
表す図。
〈本発明の効果〉
本発明は上記したように、フレッシュコンクリートから
少量のモルタルを採取して内部に含まれるセメント量を
、イオン交換樹脂による溶解と、ろ液の電気伝導度測定
によって求め、さらにモルタルの乾燥減量から水量を測
定する。
そして得られた両者の量的比較がら水セメント比を求め
る方法である。
したがって、操作が簡単であって特別な熟練を必要とせ
ず、現場でコンクリートの打設前に品質第１図
第２図
１１画水ｔメント上ヒ（％）Figure 1: A diagram showing the relationship between electrical conductivity and the cement ratio in 2 g of mortar. Figure 2: A diagram showing the relationship between the estimated water-cement ratio and the planned water-cement ratio. <Effects of the present invention> As described above, the present invention extracts a small amount of mortar from fresh concrete, determines the amount of cement contained inside by dissolving it with an ion exchange resin and measuring the electrical conductivity of the filtrate, and further The amount of water is measured from the drying loss of mortar. Then, the water-cement ratio is determined by quantitatively comparing the two obtained. Therefore, it is easy to operate, does not require special skill, and can be used to improve the quality of concrete before pouring it on site.
Claims (1)
し、 この中に含まれるセメント成分を、イオン交換樹脂で溶
解させ、 そのろ液の電気伝導度を測定し、 この電気伝導度とセメント量との比例関係から、セメン
ト量を測定し、 一方、モルタルを乾燥減量から含水量を計測し、 モルタル中のセメント量と水量から計算して行う、 フレッシュコンクリートの水セメント比の測定方法(1) Collect a small amount of mortar from fresh concrete, dissolve the cement components contained in it with ion exchange resin, measure the electrical conductivity of the filtrate, and measure the proportional relationship between this electrical conductivity and the amount of cement. A method for measuring the water-cement ratio of fresh concrete, in which the amount of cement is measured from the drying loss of the mortar, and the water content is calculated from the amount of cement and water in the mortar.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9805689A JPH02276965A (en) | 1989-04-18 | 1989-04-18 | Method for measuring water cement ratio of fresh concrete |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9805689A JPH02276965A (en) | 1989-04-18 | 1989-04-18 | Method for measuring water cement ratio of fresh concrete |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02276965A true JPH02276965A (en) | 1990-11-13 |
Family
ID=14209628
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9805689A Pending JPH02276965A (en) | 1989-04-18 | 1989-04-18 | Method for measuring water cement ratio of fresh concrete |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02276965A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05322881A (en) * | 1992-05-22 | 1993-12-07 | Tokyo Electric Power Co Inc:The | Method for discriminating quality of soil mortar in early stage for peristyle continuous underground wall constructing method |
| EP1749598A1 (en) * | 2004-03-23 | 2007-02-07 | Sintokogio, Ltd. | Casting mold forming apparatus and metal mold unit for use therein |
-
1989
- 1989-04-18 JP JP9805689A patent/JPH02276965A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05322881A (en) * | 1992-05-22 | 1993-12-07 | Tokyo Electric Power Co Inc:The | Method for discriminating quality of soil mortar in early stage for peristyle continuous underground wall constructing method |
| EP1749598A1 (en) * | 2004-03-23 | 2007-02-07 | Sintokogio, Ltd. | Casting mold forming apparatus and metal mold unit for use therein |
| EP1749598A4 (en) * | 2004-03-23 | 2007-09-19 | Sintokogio Ltd | Casting mold forming apparatus and metal mold unit for use therein |
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