JPH01198307A - Method for cooling aggregate for concrete - Google Patents
Method for cooling aggregate for concreteInfo
- Publication number
- JPH01198307A JPH01198307A JP2278088A JP2278088A JPH01198307A JP H01198307 A JPH01198307 A JP H01198307A JP 2278088 A JP2278088 A JP 2278088A JP 2278088 A JP2278088 A JP 2278088A JP H01198307 A JPH01198307 A JP H01198307A
- Authority
- JP
- Japan
- Prior art keywords
- aggregate
- concrete
- vacuum
- temp
- cooled
- 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
Links
- 238000001816 cooling Methods 0.000 title claims description 17
- 238000000034 method Methods 0.000 title claims description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 8
- 238000002156 mixing Methods 0.000 claims description 5
- 238000009834 vaporization Methods 0.000 claims description 3
- 230000008016 vaporization Effects 0.000 claims description 3
- 230000036571 hydration Effects 0.000 abstract description 9
- 238000006703 hydration reaction Methods 0.000 abstract description 9
- 108010085603 SFLLRNPND Proteins 0.000 abstract description 6
- 238000001704 evaporation Methods 0.000 abstract description 4
- 230000008020 evaporation Effects 0.000 abstract description 3
- 239000000203 mixture Substances 0.000 abstract description 3
- 238000004898 kneading Methods 0.000 abstract description 2
- 239000002352 surface water Substances 0.000 abstract description 2
- 230000007423 decrease Effects 0.000 description 5
- 239000011398 Portland cement Substances 0.000 description 3
- 239000004568 cement Substances 0.000 description 3
- 210000000988 bone and bone Anatomy 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000011400 blast furnace cement Substances 0.000 description 1
- 239000012267 brine Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- HPALAKNZSZLMCH-UHFFFAOYSA-M sodium;chloride;hydrate Chemical compound O.[Na+].[Cl-] HPALAKNZSZLMCH-UHFFFAOYSA-M 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28C—PREPARING CLAY; PRODUCING MIXTURES CONTAINING CLAY OR CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28C7/00—Controlling the operation of apparatus for producing mixtures of clay or cement with other substances; Supplying or proportioning the ingredients for mixing clay or cement with other substances; Discharging the mixture
- B28C7/0007—Pretreatment of the ingredients, e.g. by heating, sorting, grading, drying, disintegrating; Preventing generation of dust
- B28C7/0023—Pretreatment of the ingredients, e.g. by heating, sorting, grading, drying, disintegrating; Preventing generation of dust by heating or cooling
- B28C7/0038—Cooling, e.g. using ice
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、所定の水分及び所定の温度、例えば２５℃以
下において混練したコンクリートが設計上のコンクリー
ト強度を実現するために、セメントと混練前に、その細
骨材及び粗骨材を含む骨材の温度をあらかじめ低下させ
ておくコンクリート用骨材の冷却方法に関するものであ
る。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is aimed at achieving the designed strength of concrete by mixing it with a predetermined moisture content and a predetermined temperature, for example, 25°C or lower. The present invention relates to a method of cooling aggregates for concrete in which the temperature of aggregates including fine aggregates and coarse aggregates is lowered in advance.
従来からポルトランドセメントは、砂、砂利等の骨材と
混合し、コンクリートとして土木、建築工事、コンクリ
ート製品の製造に用いられてきた。Traditionally, Portland cement has been mixed with aggregates such as sand and gravel and used as concrete in civil engineering, construction work, and the manufacture of concrete products.
その中でも早強ポルトランドセメントと称するセメント
を用いたコンクリートは、早期強度が比較的大きい特徴
を有するため、主として工事を急ぐ建築工事に用いられ
てきたが、しかしながら、セメントの組成中におけるＣ
３’Ｓ、Ｃ３Ａ等の量が大きいため、混練後の水和熱の
発生が大きく、その除去が困難であり、ひいてはクラン
クの発生及び長期強度があまり期待できないという問題
があった。Among them, concrete using a cement called early-early strength Portland cement has a relatively high early-stage strength and has been used mainly for construction work that needs to be completed in a hurry.
Since the amounts of 3'S, C3A, etc. are large, a large amount of heat of hydration is generated after kneading, and its removal is difficult, resulting in problems in that crank formation and long-term strength cannot be expected.
そこで、水力発電のダムや大きな橋脚等の大塊コンクリ
ートを打設する場合には、Ｃ３Ｓ。Therefore, when placing large blocks of concrete such as hydroelectric dams or large bridge piers, C3S is used.
Ｃ３Ａが少なく、Ｃ２Ｓの多い中庸熱ポルトランドセメ
ント及び高炉セメントが開発され、コンクリート内部で
の水和熱蓄積の減少がはかられて来た。Moderate heat Portland cement and blast furnace cement, which contain less C3A and more C2S, have been developed to reduce the accumulation of hydration heat inside concrete.
しかしながら、水和熱の絶無を期することが理論的にで
きないため、種々の方法、即ち、環境温度の低い時期を
選んでコンクリートを打つとか、あるいはコンクリート
内に蓄積された水和熱を除去するため、コンクリート内
に冷却のパイプを埋設する等の方法がとられてきた。However, since it is theoretically impossible to ensure that the heat of hydration is completely eliminated, various methods are used, such as choosing a time when the environmental temperature is low to pour concrete, or removing the heat of hydration accumulated in the concrete. Therefore, methods such as burying cooling pipes in concrete have been taken.
上記のごとくセメント混練後の水和熱をとるため種々の
方法が試みられているが、近年のごとく、経済性を特に
重視するような社会状勢の中にあっては、環境温度の低
い時期を待つとか、冷却パイプを埋設する等の手段では
経済的に何時でも任意の時期、または場所においてコン
クリートを打つことができず、はなはだ不経済であり、
かつ時間的にも幾多のロスが考えられるという問題があ
った。As mentioned above, various methods have been tried to remove the heat of hydration after mixing cement, but in recent years, in a society where economic efficiency is particularly important, it is necessary to use a period when the environmental temperature is low. By waiting or by burying cooling pipes, it is not economically possible to pour concrete at any time or place, which is extremely uneconomical.
In addition, there was a problem in that there could be many losses in terms of time.
一方、コンクリート材料を混合して打込む前に予めコン
クリート材料の骨材を冷却するコンクリート骨材の冷却
方法において、表面に水を含む状態の骨材が貯蔵された
雰囲気内を真空とし、水の蒸発による蒸発潜熱によって
骨材を冷却することを特徴とするコンクリート骨材の冷
却方法及び装置に関する特開昭５７−１８８３１７の発
明もなされている。On the other hand, in a method of cooling concrete aggregates in which concrete aggregates are cooled in advance before mixing and pouring concrete materials, a vacuum is created in the atmosphere in which aggregates containing water on the surface are stored. There has also been an invention disclosed in JP-A-57-188317 relating to a method and apparatus for cooling concrete aggregate, which is characterized in that the aggregate is cooled by latent heat of evaporation due to evaporation.
しかしながら、この場合、冷却する骨材は貯蔵ビンに投
入された状態で貯蔵された骨材の雰囲気内を真空とする
ため、貯蔵ビン内の骨材の表面と底部とで均一な真空状
態が得られず、従って全体として均一な冷却とその冷却
温度のコントロールが得られにくく、かつ、冷却効率も
悪いという欠点がある。However, in this case, the aggregate to be cooled is placed in the storage bin to create a vacuum in the atmosphere of the stored aggregate, so a uniform vacuum condition can be achieved on the surface and bottom of the aggregate in the storage bin. Therefore, it is difficult to obtain uniform cooling as a whole and control of the cooling temperature, and the cooling efficiency is also poor.
本発明は、前記従来の問題点及び欠点を解消するために
なされたものであり、任意の時期、または場所において
コンクリートを打設可能で、かつ水和熱によるコンクリ
ートの温度上昇をある一定範囲内に収めることができ、
しかも均一にそして効率よく骨材の冷却が行なわれうる
コンクリート用骨材の冷却方法を提供することを目的と
したものである。The present invention has been made in order to solve the problems and drawbacks of the conventional art, and allows concrete to be poured at any time or place, and also allows the temperature rise of concrete due to heat of hydration to be within a certain range. can be accommodated in
Moreover, it is an object of the present invention to provide a method for cooling aggregate for concrete that can uniformly and efficiently cool the aggregate.
上記の目的を達成するための本発明のコンクリート用骨
材の冷却方法は、コンクリートを混練する前の細骨材及
び粗骨材またはこれらを混合した骨材を、その表面に付
着させた所定の含水分量にて真空槽内に多段式等に設け
たベルトコンベヤ等の連続移動体上に連続して供給した
状態で、その真空槽内を真空とし、その時に蒸発する水
分の気化熱をその骨材から奪うことによって、骨材の温
度を低下させることを特徴としたものであり、上記のご
とく、骨材をコンクリートと混練する前に予備冷却した
後、セメントと混練し、水和熱によるコンクリートの温
度上昇を押え、例えば平均２０℃前後の温度に保つこと
により、良好な品質のコンクリートの打設がなされる。In order to achieve the above object, the method of cooling aggregate for concrete according to the present invention is to cool fine aggregate and coarse aggregate, or a mixture of these aggregates, before mixing concrete, to a predetermined material that is attached to the surface of the aggregate. The moisture content is continuously supplied onto a continuous moving body such as a belt conveyor installed in multiple stages in a vacuum chamber, and the vacuum chamber is evacuated, and the heat of vaporization of the moisture evaporated at that time is transferred to the bones. It is characterized by lowering the temperature of the aggregate by taking away the heat from the concrete, and as mentioned above, the aggregate is pre-cooled before being mixed with concrete, and then mixed with cement to reduce the temperature of the aggregate due to the heat of hydration. By suppressing the rise in temperature and maintaining the temperature at an average of about 20°C, for example, concrete of good quality can be placed.
以下図面を参照して本発明の方法を適用した実施例の説
明をするが、第１図は本発明の方法を適用した一実施例
の骨材冷却装置の側面図であって、第２図は第１図のベ
ルトコンベヤのＡ−Ａ矢視断面図である。An embodiment to which the method of the present invention is applied will be described below with reference to the drawings. Fig. 1 is a side view of an aggregate cooling device of an embodiment to which the method of the present invention is applied, and Fig. 1 is a sectional view taken along the line A-A of the belt conveyor shown in FIG. 1. FIG.
まず、図中の１は１５％程度の表面水分をもつ骨材Ｓを
真空槽３に供給するためのホッパーで、ホッパー１に供
給された細骨材及び粗骨材、またはそれらの混合物であ
る骨材Ｓは、供給側真空弁２を経て各段同期駆動されて
いるヘルドコンベヤのベルト４上に落下する。First, 1 in the figure is a hopper for supplying the aggregate S having a surface moisture of about 15% to the vacuum chamber 3, which is fine aggregate, coarse aggregate, or a mixture thereof supplied to hopper 1. The aggregate S passes through the supply vacuum valve 2 and falls onto the belt 4 of the heald conveyor, which is driven synchronously at each stage.
その時、ベルト４の速度と供給される骨材Ｓの供給量を
供給側真空弁２によって調節するか、あるいは望むらく
は別途にダンパーを設けて調節しても良いし、更には回
転式の定量供給装置を使用しても良いが、第２図のごと
くヘルド４の両側に附属しているスカート６を越えない
程度にして順次骨材Ｓを供給してゆく。At that time, the speed of the belt 4 and the amount of aggregate S to be supplied may be adjusted by the supply side vacuum valve 2, or preferably by providing a damper separately, or even by a rotary metering device. A feeding device may be used, but as shown in FIG. 2, the aggregate S is sequentially fed so as not to exceed the skirts 6 attached to both sides of the heald 4.
いま、第１図の全段のベルト４が同じ速度で走行し、ホ
ッパー１からスカート６を越えない程度に連続して骨材
Ｓを供給すれば、遂には最下段のベルト４上迄各段同じ
厚みの骨材Ｓを保有することになる。Now, if the belts 4 in all stages in FIG. Aggregates S of the same thickness will be held.
そして、最下段のベルト４から排出側真空弁７に骨材Ｓ
が落下する直前で各段の駆動プーリ−５を停止して各膜
均一に骨材Ｓを保有し、同時に供給側真空弁２を閉じて
骨材Ｓの供給を停止する。Then, the aggregate S is transferred from the belt 4 at the lowest stage to the discharge side vacuum valve 7.
Immediately before the film falls, the driving pulleys 5 at each stage are stopped to hold the aggregate S uniformly in each film, and at the same time, the supply side vacuum valve 2 is closed to stop the supply of the aggregate S.
次に、ブラインチラー１１によって一５°Ｃ程度迄充分
冷却されたコールドトラップ９を経て真空ポンプ１４に
至る配管１５の途中にある真空弁８を開いて真空ポンプ
１４を駆動する。Next, the vacuum valve 8 in the middle of the pipe 15 that passes through the cold trap 9, which has been sufficiently cooled to about 15° C. by the brine chiller 11, and reaches the vacuum pump 14 is opened to drive the vacuum pump 14.
駆動後しばらくすると、真空槽３内の圧力は低下し、骨
材Ｓの温度に対比する水の飽和圧力に達し、更にその圧
力よりも低くなる方向に向って圧力は低下してゆく。After a while after driving, the pressure inside the vacuum chamber 3 decreases, reaching the saturation pressure of water relative to the temperature of the aggregate S, and the pressure further decreases in a direction lower than that pressure.
その時、骨ＪｒＡＳに附着している表面水は、沸騰を始
めて蒸発し、真空弁８を経てコールドトラップ９内にあ
る冷却器１０の表面に接触する。At that time, the surface water adhering to the bone JrAS begins to boil and evaporate, and comes into contact with the surface of the cooler 10 in the cold trap 9 via the vacuum valve 8.
そうすると、水蒸気は冷却器」Ｏの表面温度より高い場
合は冷却器１０の表面で液化し、ドレンとしてコールド
トラップ９中に溜まり、遂にはドレンタンク１２へ落ち
てゆき、ドレンタンク１２に溜まったドレンは真空抜き
出しポンプ１３を経て大気中へ放出される。Then, if the water vapor is higher than the surface temperature of the cooler 10, it liquefies on the surface of the cooler 10, accumulates in the cold trap 9 as drain, and finally falls into the drain tank 12. is discharged into the atmosphere via the vacuum extraction pump 13.
このように真空排気を続けると、骨材Ｓの表面に附着し
ている水分は蒸発を継続し、骨材温度は次第に下がって
ゆき、遂にはコールドトラップ９の中の冷却器１０の表
面温度の飽和圧近く迄降下し、はぼ冷却器１０の表面温
度より３〜４℃高い温度迄骨材Ｓの温度は低下する。If the evacuation continues in this way, the water adhering to the surface of the aggregate S will continue to evaporate, the aggregate temperature will gradually decrease, and the surface temperature of the cooler 10 in the cold trap 9 will finally drop. The temperature of the aggregate S decreases to near the saturation pressure, and the temperature of the aggregate S decreases to a temperature that is 3 to 4° C. higher than the surface temperature of the condenser 10.
一方、蒸発する水分はコールドトラップ９でトラップさ
れるため、真空ポンプ１４中には飛来せずに常に真空度
が維持できる。On the other hand, since the evaporated water is trapped in the cold trap 9, it does not fly into the vacuum pump 14, and the degree of vacuum can be maintained at all times.
このようにして冷却された骨材Ｓは、真空破り弁１６を
開いて真空槽３を大気圧にし、排出側真空弁７を開き、
各段の駆動プーリー５を駆動することによって全量冷却
されたまま排出することができる。The aggregate S cooled in this way opens the vacuum break valve 16 to bring the vacuum chamber 3 to atmospheric pressure, opens the discharge side vacuum valve 7,
By driving the drive pulleys 5 at each stage, the entire amount can be discharged while being cooled.
そして、次の新しい骨材Ｓについては前記と同様の操作
を繰返せばよいことになる。Then, for the next new aggregate S, the same operation as described above can be repeated.
なお、上記の実施例により冷却される骨材Ｓはその真空
槽３内に設けたベルトコンベヤ上に供給する以前にすで
に適宜な手段により、その表面に所定の含水分量例えば
１５％程度の水分を持たせているが、この水分は真空槽
３内で散水ノズル等適宜な手段により骨材Ｓに与えられ
るようにしても良い。In addition, before the aggregate S to be cooled in the above embodiment is supplied onto the belt conveyor provided in the vacuum chamber 3, its surface is already coated with a predetermined moisture content, for example, about 15%, by an appropriate means. However, this moisture may be applied to the aggregate S within the vacuum chamber 3 using a suitable means such as a water spray nozzle.
以上に説明したごとき、本発明の冷却方法を用いてコン
クリート用骨材を冷却する装置をコンクリート打設現場
近傍に設ければ、任意の時期、または場所においてもク
ラックの発生しない良好なコンクリートの打設が可能で
あり、かつコンクリートの水和熱によるコンクリートの
温度上昇をある一定範囲内に容易に収めることができる
という効果がある。As explained above, if a device for cooling concrete aggregate using the cooling method of the present invention is installed near the concrete placement site, good concrete placement without cracking can be achieved at any time or place. This method has the effect that the temperature rise of concrete due to the heat of hydration of concrete can be easily kept within a certain range.
特に、本発明の方法では、連続移動体上に骨材を連続し
て供給した状態で真空とし、蒸発する水分の気化熱を骨
材から奪うようにしているので、骨材が一個所に堆積さ
れることがないので、骨材が全体として均一に冷却され
ることになり、すべての骨材を均一、かつ平均的に、し
かも効率良く冷却することができ、しかもその冷却温度
のコントロールも容易に行なわれるという利点があり、
その結果、打設後のコンクリートの品質の向上をはかる
ことができる。In particular, in the method of the present invention, a vacuum is created while the aggregate is continuously supplied onto the continuous moving body, and the heat of vaporization of the evaporating water is taken away from the aggregate, so that the aggregate is not deposited in one place. Since the aggregate is cooled uniformly as a whole, all aggregates can be cooled uniformly, evenly, and efficiently, and the cooling temperature can be easily controlled. It has the advantage that it is carried out in
As a result, it is possible to improve the quality of concrete after pouring.
第１図は本発明の方法を適用した一実施例の骨材冷却装
置の側面図であって、第２図は第１図のベルトコンベヤ
のＡ−Ａ矢視断面図である。
１・・・ホッパー、２・・・供給側真空弁、４・・・連
続移動体（ベルトコンベヤのベルト）、７・・・排出側
真空弁、８・・・真空弁、１４・・・真空ポンプ、Ｓ・
・・骨材。
代理人 弁理士 小 川 信 −FIG. 1 is a side view of an aggregate cooling device according to an embodiment to which the method of the present invention is applied, and FIG. 2 is a sectional view taken along the line A-A of the belt conveyor shown in FIG. 1... Hopper, 2... Supply side vacuum valve, 4... Continuous moving body (belt of belt conveyor), 7... Discharge side vacuum valve, 8... Vacuum valve, 14... Vacuum Pump, S.
··aggregate. Agent Patent Attorney Nobuo Ogawa −
Claims (1)
て真空槽内に設けた連続移動体上に連続して供給した状
態で該真空槽内を真空とし、その時に蒸発する水分の気
化熱を上記骨材から奪うことによって骨材の温度を低下
させるコンクリート用骨材の冷却方法。The aggregate before mixing concrete is continuously supplied at a predetermined moisture content onto a continuous moving body installed in a vacuum tank, and the vacuum tank is evacuated, and the heat of vaporization of the water that evaporates at that time is A method for cooling aggregates for concrete, which lowers the temperature of the aggregate by depriving the aggregate of
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2278088A JP2601298B2 (en) | 1988-02-04 | 1988-02-04 | Cooling method for concrete aggregate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2278088A JP2601298B2 (en) | 1988-02-04 | 1988-02-04 | Cooling method for concrete aggregate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01198307A true JPH01198307A (en) | 1989-08-09 |
| JP2601298B2 JP2601298B2 (en) | 1997-04-16 |
Family
ID=12092184
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2278088A Expired - Fee Related JP2601298B2 (en) | 1988-02-04 | 1988-02-04 | Cooling method for concrete aggregate |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2601298B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03183509A (en) * | 1989-12-13 | 1991-08-09 | Mitsubishi Electric Corp | Precooling method for concrete |
| CN105643803A (en) * | 2015-12-17 | 2016-06-08 | 中国水利水电第八工程局有限公司 | Fine aggregate precooling device for concrete production |
| EP3862157A1 (en) * | 2020-02-04 | 2021-08-11 | I.C.M. S.r.l. | Method and plant for cooling a mixture of concrete ingredients |
| WO2022011176A3 (en) * | 2020-07-08 | 2022-02-17 | Nitrocrete Ip, Llc | System and method for concrete manufacturing using coolant dispensing system onto aggregate carried conveyance device |
-
1988
- 1988-02-04 JP JP2278088A patent/JP2601298B2/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03183509A (en) * | 1989-12-13 | 1991-08-09 | Mitsubishi Electric Corp | Precooling method for concrete |
| CN105643803A (en) * | 2015-12-17 | 2016-06-08 | 中国水利水电第八工程局有限公司 | Fine aggregate precooling device for concrete production |
| EP3862157A1 (en) * | 2020-02-04 | 2021-08-11 | I.C.M. S.r.l. | Method and plant for cooling a mixture of concrete ingredients |
| WO2021156379A3 (en) * | 2020-02-04 | 2021-09-16 | Icm S.R.L. | Method and plant for cooling a mixture of ingredients of concrete |
| WO2022011176A3 (en) * | 2020-07-08 | 2022-02-17 | Nitrocrete Ip, Llc | System and method for concrete manufacturing using coolant dispensing system onto aggregate carried conveyance device |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2601298B2 (en) | 1997-04-16 |
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