JPH0155212B2 - - Google Patents
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- Publication number
- JPH0155212B2 JPH0155212B2 JP58149042A JP14904283A JPH0155212B2 JP H0155212 B2 JPH0155212 B2 JP H0155212B2 JP 58149042 A JP58149042 A JP 58149042A JP 14904283 A JP14904283 A JP 14904283A JP H0155212 B2 JPH0155212 B2 JP H0155212B2
- Authority
- JP
- Japan
- Prior art keywords
- cement
- weight
- parts
- curing
- temperature
- 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
Links
- 239000004568 cement Substances 0.000 claims description 65
- 239000000203 mixture Substances 0.000 claims description 33
- 238000004519 manufacturing process Methods 0.000 claims description 17
- 238000009415 formwork Methods 0.000 claims description 16
- 150000003839 salts Chemical class 0.000 claims description 16
- 239000011396 hydraulic cement Substances 0.000 claims description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 15
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 claims description 12
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims description 12
- 238000010438 heat treatment Methods 0.000 claims description 11
- 150000003467 sulfuric acid derivatives Chemical class 0.000 claims description 10
- RGHNJXZEOKUKBD-SQOUGZDYSA-N D-gluconic acid Chemical group OC[C@@H](O)[C@@H](O)[C@H](O)[C@@H](O)C(O)=O RGHNJXZEOKUKBD-SQOUGZDYSA-N 0.000 claims description 8
- 238000002156 mixing Methods 0.000 claims description 7
- 239000002253 acid Substances 0.000 claims description 6
- YGSDEFSMJLZEOE-UHFFFAOYSA-N salicylic acid Chemical compound OC(=O)C1=CC=CC=C1O YGSDEFSMJLZEOE-UHFFFAOYSA-N 0.000 claims description 6
- 229910052744 lithium Inorganic materials 0.000 claims description 5
- 229910052751 metal Inorganic materials 0.000 claims description 5
- 239000002184 metal Substances 0.000 claims description 5
- RGHNJXZEOKUKBD-UHFFFAOYSA-N D-gluconic acid Natural products OCC(O)C(O)C(O)C(O)C(O)=O RGHNJXZEOKUKBD-UHFFFAOYSA-N 0.000 claims description 4
- FEWJPZIEWOKRBE-JCYAYHJZSA-N Dextrotartaric acid Chemical compound OC(=O)[C@H](O)[C@@H](O)C(O)=O FEWJPZIEWOKRBE-JCYAYHJZSA-N 0.000 claims description 4
- FEWJPZIEWOKRBE-UHFFFAOYSA-N Tartaric acid Natural products [H+].[H+].[O-]C(=O)C(O)C(O)C([O-])=O FEWJPZIEWOKRBE-UHFFFAOYSA-N 0.000 claims description 4
- 229910052782 aluminium Inorganic materials 0.000 claims description 4
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 4
- 235000015165 citric acid Nutrition 0.000 claims description 4
- 229910052733 gallium Inorganic materials 0.000 claims description 4
- 239000000174 gluconic acid Substances 0.000 claims description 4
- 235000012208 gluconic acid Nutrition 0.000 claims description 4
- 239000011975 tartaric acid Substances 0.000 claims description 4
- 235000002906 tartaric acid Nutrition 0.000 claims description 4
- GYHNNYVSQQEPJS-UHFFFAOYSA-N Gallium Chemical compound [Ga] GYHNNYVSQQEPJS-UHFFFAOYSA-N 0.000 claims description 3
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims description 3
- 229910000288 alkali metal carbonate Inorganic materials 0.000 claims description 3
- 150000008041 alkali metal carbonates Chemical class 0.000 claims description 3
- 150000002739 metals Chemical class 0.000 claims description 3
- FJKROLUGYXJWQN-UHFFFAOYSA-N papa-hydroxy-benzoic acid Natural products OC(=O)C1=CC=C(O)C=C1 FJKROLUGYXJWQN-UHFFFAOYSA-N 0.000 claims description 3
- 229960004889 salicylic acid Drugs 0.000 claims description 3
- 229910052716 thallium Inorganic materials 0.000 claims description 3
- -1 alkali metal salt Chemical class 0.000 claims description 2
- BKVIYDNLLOSFOA-UHFFFAOYSA-N thallium Chemical compound [Tl] BKVIYDNLLOSFOA-UHFFFAOYSA-N 0.000 claims description 2
- 150000007513 acids Chemical class 0.000 claims 1
- 229910052783 alkali metal Inorganic materials 0.000 claims 1
- DIZPMCHEQGEION-UHFFFAOYSA-H aluminium sulfate (anhydrous) Chemical compound [Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O DIZPMCHEQGEION-UHFFFAOYSA-H 0.000 claims 1
- 238000001723 curing Methods 0.000 description 47
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 14
- 239000004567 concrete Substances 0.000 description 14
- 239000011398 Portland cement Substances 0.000 description 12
- 239000004576 sand Substances 0.000 description 10
- 238000000465 moulding Methods 0.000 description 9
- 238000000034 method Methods 0.000 description 8
- 239000011734 sodium Substances 0.000 description 7
- 239000003795 chemical substances by application Substances 0.000 description 6
- 239000004570 mortar (masonry) Substances 0.000 description 6
- 238000005187 foaming Methods 0.000 description 5
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 229910052700 potassium Inorganic materials 0.000 description 3
- 229910052708 sodium Inorganic materials 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- AEMRFAOFKBGASW-UHFFFAOYSA-N Glycolic acid Chemical compound OCC(O)=O AEMRFAOFKBGASW-UHFFFAOYSA-N 0.000 description 2
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 2
- 239000003638 chemical reducing agent Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000013007 heat curing Methods 0.000 description 2
- 238000004898 kneading Methods 0.000 description 2
- JVTAAEKCZFNVCJ-UHFFFAOYSA-N lactic acid Chemical compound CC(O)C(O)=O JVTAAEKCZFNVCJ-UHFFFAOYSA-N 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 238000004904 shortening Methods 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- HELHAJAZNSDZJO-OLXYHTOASA-L sodium L-tartrate Chemical compound [Na+].[Na+].[O-]C(=O)[C@H](O)[C@@H](O)C([O-])=O HELHAJAZNSDZJO-OLXYHTOASA-L 0.000 description 2
- 229910000029 sodium carbonate Inorganic materials 0.000 description 2
- 239000001433 sodium tartrate Substances 0.000 description 2
- 229960002167 sodium tartrate Drugs 0.000 description 2
- 235000011004 sodium tartrates Nutrition 0.000 description 2
- 239000004575 stone Substances 0.000 description 2
- 230000009974 thixotropic effect Effects 0.000 description 2
- 239000002023 wood Substances 0.000 description 2
- BJEPYKJPYRNKOW-REOHCLBHSA-N (S)-malic acid Chemical compound OC(=O)[C@@H](O)CC(O)=O BJEPYKJPYRNKOW-REOHCLBHSA-N 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 1
- 206010067482 No adverse event Diseases 0.000 description 1
- KDYFGRWQOYBRFD-UHFFFAOYSA-N Succinic acid Natural products OC(=O)CCC(O)=O KDYFGRWQOYBRFD-UHFFFAOYSA-N 0.000 description 1
- 241001455273 Tetrapoda Species 0.000 description 1
- 235000011941 Tilia x europaea Nutrition 0.000 description 1
- 239000012615 aggregate Substances 0.000 description 1
- BJEPYKJPYRNKOW-UHFFFAOYSA-N alpha-hydroxysuccinic acid Natural products OC(=O)C(O)CC(O)=O BJEPYKJPYRNKOW-UHFFFAOYSA-N 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000010425 asbestos Substances 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 239000011400 blast furnace cement Substances 0.000 description 1
- KDYFGRWQOYBRFD-NUQCWPJISA-N butanedioic acid Chemical compound O[14C](=O)CC[14C](O)=O KDYFGRWQOYBRFD-NUQCWPJISA-N 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- XFWJKVMFIVXPKK-UHFFFAOYSA-N calcium;oxido(oxo)alumane Chemical compound [Ca+2].[O-][Al]=O.[O-][Al]=O XFWJKVMFIVXPKK-UHFFFAOYSA-N 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000007872 degassing Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 239000010881 fly ash Substances 0.000 description 1
- 239000004088 foaming agent Substances 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 239000010440 gypsum Substances 0.000 description 1
- 229910052602 gypsum Inorganic materials 0.000 description 1
- 238000006703 hydration reaction Methods 0.000 description 1
- 239000004310 lactic acid Substances 0.000 description 1
- 235000014655 lactic acid Nutrition 0.000 description 1
- 239000004571 lime Substances 0.000 description 1
- 239000001630 malic acid Substances 0.000 description 1
- 235000011090 malic acid Nutrition 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 229910052895 riebeckite Inorganic materials 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 229910052712 strontium Inorganic materials 0.000 description 1
- 230000008961 swelling Effects 0.000 description 1
- YTQVHRVITVLIRD-UHFFFAOYSA-L thallium sulfate Chemical compound [Tl+].[Tl+].[O-]S([O-])(=O)=O YTQVHRVITVLIRD-UHFFFAOYSA-L 0.000 description 1
- 229940119523 thallium sulfate Drugs 0.000 description 1
- 229910000374 thallium(I) sulfate Inorganic materials 0.000 description 1
- 239000002562 thickening agent Substances 0.000 description 1
- 210000002268 wool Anatomy 0.000 description 1
Landscapes
- Curing Cements, Concrete, And Artificial Stone (AREA)
Description
本発明は、セメント成型体を急速高温養生によ
つて極めて短時間（１〜３時間）で製造する方法
に関するものである。セメント成型体としては、
石綿セメント板、パルプセメント板、木毛セメン
ト板、木片セメント板、GRC、セメント瓦、モ
ルタル板、テラゾーブロツク、コンクリート板、
コンクリートパイル、ヒユーム管、Ｕ字溝、コン
クリートブロツク、テトラポツト、コンクリート
枕木、ALC等の土木、建築用のセメント、モル
タル、コンクリート製品があげられる。
製品により異なるが、従来、セメント成型体を
製造するには、ポルトランドセメント、水及び骨
材を調合して混練りし、型枠に充填後、常温（通
常の気温）で２〜４時間前養生する。ついで、水
蒸気を用いて、11〜33℃／時間の速度で、60〜70
℃まで昇温し、該養生温度を４〜８時間保持した
後に蒸気を止め、６〜12時間の自然冷却を待つて
脱型している〔特開昭55−20252号、特開昭57−
22151号、特公昭57−17871号公報、日曹マスター
ビルダーズ(株)の技術試料No.Ｌ−001“蒸気養生−
ACI517委員会報告”、1965年８月刊〕。
従来の方法では、セメント成型体の生産サイク
ルは１〜３サイクル／日である。生産時間を単に
短縮したのではコンクリートは十分に硬化しな
い。また、従来の養生条件よりも、前養生時間を
短縮し、昇温速度及び養生温度を上昇させると、
セメント成型体には膨張、発泡及び亀裂が発生
し、健全な製品が得られない。
かかる従来の蒸気養生法の成形サイクルが長い
という欠点を改良する目的で、普通ポルトランド
セメントに早強セメント、即ち、カルシウムアル
ミネート、石灰と石膏の混合物を５重量％以上、
必要により炭酸ソーダと有機酸（例えばグルコン
酸、クエン酸、酒石酸あるいはこれらのNa、Ｋ
の塩）および発泡剤であるアルミニウム粉、水、
細骨材を配合した水硬性セメント配合物を、型枠
に打設し、１〜２時間前養生後、高温高圧蒸気養
生（昇温温度80℃／時間、180℃、10気圧）もし
くは常圧蒸気養生（昇温温度40℃／時間、60℃、
１気圧）し、次いで室温まで４〜５時間かけて冷
却して脱型し、脱型直後の圧縮強度が82〜90Kg／
cm2の軽量セメント成型品を製造する方法が提案さ
れた（特開昭50−110420号公報）。
この方法は、水硬性セメント配合物を型枠に打
設後の昇温速度を速めることにより、成形サイク
ルを短縮させるものであるが、依然として相当時
間の前養生が必要であり、また、蒸気養生後、脱
型する迄の放冷時間に５〜６時間要するので、未
だ成形サイクルの十分な短縮とは言えない。
本発明者等は、セメント混和剤を種々検討し、
前養生の必要性の有無、蒸気養生後の放冷の必要
性の有無を検討したところ、特定の硫酸塩をセメ
ント混和剤として用いる場合は開放式型枠でも、
前養生を必要とせず、成型後直ちに昇温速度40
℃／時間以上、かつ、養生温度80℃以上の急速高
温養生を行うことができ、これによつて、養生時
間１〜３時間で欠点のない健全なセメント成型体
が得られ、生産サイクルは10サイクル／日以上可
能であることを見い出し、先に、水硬性セメント
に対して、リチウム、アルミニウム、ガリウム、
タリウムの硫酸塩およびそれらの金属を含む硫酸
複塩の１種または２種以上を0.1〜20重量％の割
合で添加した水硬性セメント配合物を成型後、高
温養生することを特徴とするセメント成型体の製
造方法を出願した（昭和58年７月12日出願）。
本発明はこの先願において、型枠への打設が容
易な水硬性セメント配合物を見い出したもので、
前記硫酸塩の他に、特定の他の混和剤を併用する
ことにより、水硬性セメント配合物が打設作業に
適した流動性を保つ時間を必要十分に長くするこ
とを可能ならしめるものである。
即ち、本発明は、セメント100重量部、細骨材
０重量部〜適量、粗骨材０重量部〜適量、水適量
および下記の組成割合の混和剤１〜20重量部
(a) リチウム、アルミニウム、ガリウム、タリウ
ムの硫酸塩またはそれらの金属を含む硫酸複塩
の１種または２種以上の硫酸塩 １重量部
(b) オキシカルボン酸またはその塩
0.01〜0.7重量部
(c) アルカリ金属の炭酸塩 ０〜４重量部
の割合で配合された水硬性セメント配合物を型内
に打設し、これを40℃〜120℃／時間の昇温速度
により80〜110℃の温度で急速高温養生すること
を特徴とするセメント成型体の製造方法を提供す
るものである。
本発明の実施において、水硬性セメントとして
は、普通ポルトランドセメント、早強ポルトラン
ドセメント、中庸熱ポルトランドセメント、耐硫
酸塩ポルトランドセメント、白色ポルトランドセ
メント、高炉セメント、シリカセメント、フライ
アツシユセメント等が挙げられる。
細骨材としては川砂、砕砂、硅砂、人工軽量砂
等が挙げられ、これらはセメント100重量部に対
し、０重量部〜適量、モルタル、コンクリート製
品の場合には100〜300重量部の割合で用いる。粗
骨材としては川砂利、砕石が一般であり、モルタ
ル成型品を得る場合は配合されないが、コンクリ
ート成型品を製造する場合は200〜400重量部の割
合で、また、細骨材率が27〜45重量％となる割合
で一般に利用される。水はセメントの水和反応に
必要な量であつて、セメント配合物が型に打設さ
れやすい流動性を保つ量、配合される。コンクリ
ート成型品を目的とするときは、従来、表面が平
滑な製品を得るには、セメント配合物のスランプ
値が５以上となるように水は配合されていたが、
本発明においては特定の混和剤が配合されてお
り、セメント配合物はチキソトロピツク性に優れ
るので、スランプ値が０であつても、型枠に打設
後、型枠に振動を与えれば、表面が平滑なコンク
リート成型品を得ることができる。
次にセメント混和剤成分について述べる。
(a)成分の硫酸塩としては、Al、Li、Tl、Gaの
硫酸塩、これらの複塩、例えばNH4AlSO4等が
あげられる。これらの硫酸塩や硫酸複塩は、無水
物あるいは有水物のいずれの形でも使用でき、粉
末状あるいは水溶液としても使用できる。
硫酸塩としては、CaSO4、K2SO4、Na2SO4等
もセメント混和剤としてよく使用されているが、
CaSO4、Na2SO4を用いたときは脱型直後のセメ
ント成型品の圧縮強度が低い欠点があり、K2SO4
を用いたときは圧縮強度の高い製品を得ることが
できるが、80℃以上の蒸気養生条件ではひび割れ
た製品しか得ることができない。
次に、セメント配合物の流動性を改良する
(b)成分のオキシカルボン酸またはその金属塩と
しては、グルコン酸、クエン酸、酒石酸、サリチ
ル酸またはこれらのNa、Li、Ｋ、Sr、Ca塩等が
あげられる。特に、グルコン酸、クエン酸、酒石
酸、サリチル酸またはこれらのNa塩、Ｋ塩は、
コハク酸、リンゴ酸、グリコール酸、乳酸もしく
はこれらの金属塩より特にセメント組成物の流動
性の改良効果が優れる。
(c)成分のアルカリ金属の炭酸塩としては、
Na2CO3、K2CO3、Li2CO3があげられる。この炭
酸塩の添加は、セメント成型品の圧縮強度とセメ
ント配合物の流動性の改良に役立つ。
混和剤の配合組成は、(a)成分の硫酸塩１重量部
に対し、(b)成分のオキシカルボン酸またはその塩
が0.01〜0.7重量部、(c)成分の炭酸塩は４重量部
以下の割合で用いる。また、混和剤は、セメント
100重量部に対し、１〜20重量部、好ましくは３
〜15重量部の割合で用いる。混和剤の多量の使用
は得られるセメント成型品の機械的強度を低下さ
せるので好ましくない。
これら混和剤の他に、セメント組成物に樹脂充
填剤、顔料、減水剤、空気連行剤（AE剤）、増粘
剤等を必要により配合できる。
AE剤は従来コンクリートの空気量を増加させ
るので、これまで高温養生には好ましくないと考
えられていたが、本発明の前記特定の硫酸塩や硫
酸複塩と併用するときには、セメント成型体の表
面及び内部組織に発泡や膨張が見られず、良好な
表面性状及び組織構造が得られた。これは、養生
初期の段階で骨格が形成され、該骨格が膨張抑制
方向に働くので、AE剤で連行された空気の熱膨
張が生じないものと推測される。いずれにせよ、
本発明方法では、AE剤を膨張現象の恐れなく使
用でき、AE剤本来の作用効果を充分に発揮させ
ることができるので、耐凍結融解性を向上させる
ことができる。
上記水硬性セメントと、特定の硫酸塩や硫酸複
塩、オキシカルボン酸塩に水及び骨材（砂等の細
骨材と砂利や砕石等の粗骨材の一方又は双方）、
更に必要により他の促進剤、遅延剤、減水剤、炭
酸塩等の混和剤を添加して混練りし、型枠に投入
充填（打設）し、次いで40℃／時間以上で80℃以
上に昇温し、この水硬性セメント配合物を１〜３
時間、大気圧下に80℃以上の温度で急速高温養生
する。
打設後、常温で前置時間（前養生）を取つても
よいが、セメント成型体の生産サイクルを増すた
め、打設終了後前養生なしに直ちに急速な昇温が
行われる。昇温速度は40℃／時間以上、好ましく
は60〜120℃／時間がよく、また、この速度範囲
では得られるセメント成型品に何等の悪影響も生
じない。養生時間は80℃以上の高温、好ましくは
90〜110℃の高温を15〜60分間保持すればよい。
100℃を越える高温養生を行うときは、気密性の
ある養生装置が必要である。例えば成型体をシー
トで包み、加圧されたスチームを通気すれば100
℃を越える高温養生ができる。
高温養生のための加熱媒体としては、一般の蒸
気養生に用いられている高温加圧水蒸気が適して
いる。その他の加熱養生方法、例えば電気養生、
電熱養生、高周波養生や加熱空気養生、赤外線加
熱養生も何等の支障なく使用できる。
セメント成型体は上記の高温養生後、直ちに脱
型され、全ての製造工程が終了する。養生の熱効
率を上げるためには、多少（10分〜２時間）の自
然放冷（ソーキング）を行えば効果的である。
このようにして、養生時間１〜３時間で得られ
たセメント成型体（セメント、モルタルあるいは
コンクリート製品）は製品の表面および内部組織
に膨張、発泡、亀裂等の欠点がなく、必要十分な
脱型強度（100〜200Kg／cm）があり、脱型後の強
度の増進も通常の蒸気養生製品と同等である。
本発明の実施において、(a)成分の硫酸塩や硫酸
複塩が、水硬性セメント配合物の急速高温養生に
おいて、該セメント配合物の膨張、発泡、亀裂を
抑止して硬化を促進する作用をなしているものと
思われる。
本発明の方法によれば、水硬性セメント配合物
のチキソトロピツク性が優れるので型枠への打設
が容易であり、また極めて短時間に脱型直後の圧
縮強度として80Kg／cm2以上が得られ、表面が平滑
なセメント成型品を大気圧下で開放式型枠を用い
て製造できる利点を有する。また、本発明法では
従来の高温高圧養生法のように大きな蒸気圧を隔
室内に確保する必要がないので、養生用設備に格
別の圧力保持手段を付する必要が全くなく、従来
の常圧蒸気養生設備をそのまま使用することがで
きる。型枠も設備及び運転コストの高い閉鎖式型
枠を使用する必要がなく、通常の開放式型枠をそ
のまま使用することができる。
即ち、本発明によれば、急速高温養生を膨張現
象の危惧なく安全に行なえるので、早期強度発現
や養生時間の短縮、生産サイクルの増大という課
題を、型枠や養生用装置の設備費や運転コストの
過大な増大を招かずに容易に達成できるのであ
り、また、成型体自体の品質面においても、比較
的大きい細孔半径における細孔容積を少なくした
り、耐凍結融解性を向上させたり、中性化を抑制
する等の改善効果があるのである。
次に、混和剤の種類、添加量、養生温度を種々
変更して、水硬性セメント配合物を蒸気養生した
本発明の実施例並びに比較例を、第１表乃至第５
表に整理して示す。
実施例 １
普通ポルトランドセメント100重量部、標準砂
200重量部、水60重量部に、表１に示す混和剤を
同表に示す割合で配合してセメント配合物を調製
し、このセメント配合物のフロー値の経時変化を
測定した。結果を同表に示す。
次いで、フロー値が130mm以上であるうちにこ
れらセメント配合物を開放式鋼製型枠内に充填
し、振動を型枠に与えて脱泡後、30℃より90℃ま
で１時間かけて昇温を行ない、90℃で蒸気養生を
60分行なつた後、蒸気を止め、直にセメント成型
品を脱型し、この外観を調べた。外観の判定は、
成型体全体について膨張、発泡、亀裂の有無、大
小、数を肉眼観察して行なつた。
The present invention relates to a method for producing cement molded bodies in an extremely short time (1 to 3 hours) by rapid high temperature curing. As a cement molded body,
Asbestos cement board, pulp cement board, wood wool cement board, wood chip cement board, GRC, cement tile, mortar board, terrazzo block, concrete board,
Examples include cement, mortar, and concrete products for civil engineering and construction, such as concrete piles, humid pipes, U-shaped grooves, concrete blocks, tetrapods, concrete sleepers, and ALC. Although it varies depending on the product, conventionally, to manufacture cement molded bodies, Portland cement, water, and aggregate are mixed and mixed, filled into molds, and then pre-cured at room temperature (normal temperature) for 2 to 4 hours. do. Then, using water vapor at a rate of 11-33℃/hour, 60-70℃
After raising the temperature to ℃ and maintaining the curing temperature for 4 to 8 hours, the steam is stopped and the mold is removed after waiting for 6 to 12 hours of natural cooling [JP-A-55-20252, JP-A-57-
No. 22151, Special Publication No. 17871, Nisso Master Builders Co., Ltd. Technical Sample No. L-001 “Steam Curing”
ACI517 Committee Report, published August 1965]. In the conventional method, the production cycle of cement moldings is 1 to 3 cycles/day. If the production time is simply shortened, the concrete will not harden sufficiently. Also, By shortening the pre-curing time and increasing the heating rate and curing temperature compared to conventional curing conditions,
Expansion, foaming, and cracks occur in the cement molded body, making it impossible to obtain a healthy product. In order to improve the shortcoming of the long molding cycle of the conventional steam curing method, at least 5% by weight of early-strengthening cement, that is, a mixture of calcium aluminate, lime and gypsum, is added to ordinary Portland cement.
If necessary, add sodium carbonate and an organic acid (e.g. gluconic acid, citric acid, tartaric acid, or these Na, K)
salt) and foaming agent aluminum powder, water,
A hydraulic cement mixture containing fine aggregate is poured into a formwork, and after curing for 1 to 2 hours, it is cured with high temperature and high pressure steam (heating temperature 80℃/hour, 180℃, 10 atm) or normal pressure. Steam curing (heating temperature 40℃/hour, 60℃,
1 atm), then cooled to room temperature for 4 to 5 hours and demolded, and the compressive strength immediately after demolding was 82 to 90 kg/
A method for manufacturing lightweight cement molded products of cm 2 was proposed (Japanese Patent Application Laid-open No. 110420/1983). This method shortens the molding cycle by speeding up the heating rate after casting the hydraulic cement mixture into the formwork, but it still requires a considerable amount of pre-curing time and requires steam curing. After that, it takes 5 to 6 hours to cool the mold until it is demolded, so it cannot be said that the molding cycle is sufficiently shortened. The present inventors studied various cement admixtures, and
After considering the necessity of pre-curing and the necessity of cooling after steam curing, we found that if a specific sulfate is used as a cement admixture, even in an open formwork,
Temperature increase rate of 40% immediately after molding without requiring pre-curing
It is possible to perform rapid high-temperature curing at a temperature of 80°C or higher and a curing temperature of 80°C or higher.This allows a healthy cement molded body with no defects to be obtained within a curing time of 1 to 3 hours, and the production cycle is 10 degrees. We discovered that it is possible to use lithium, aluminum, gallium,
Cement molding characterized by molding a hydraulic cement mixture containing 0.1 to 20% by weight of thallium sulfate and one or more sulfate double salts containing these metals and then curing at a high temperature. The company applied for a method for manufacturing the body (filed on July 12, 1988). In this prior application, the present invention discovered a hydraulic cement compound that is easy to cast into formwork.
By using certain other admixtures in addition to the above-mentioned sulfate, it is possible to extend the time necessary and sufficient for the hydraulic cement mixture to maintain fluidity suitable for pouring work. . That is, the present invention comprises: 100 parts by weight of cement, 0 to appropriate amount of fine aggregate, 0 to appropriate amount of coarse aggregate, an appropriate amount of water, and 1 to 20 parts by weight of an admixture having the following composition ratio (a) lithium, aluminum 1 part by weight of sulfates of , gallium, thallium, or sulfate double salts containing these metals (b) Oxycarboxylic acid or its salt
0.01 to 0.7 parts by weight (c) Alkali metal carbonate A hydraulic cement mixture containing 0 to 4 parts by weight is poured into a mold, and heated at a heating rate of 40°C to 120°C/hour. The present invention provides a method for producing a cement molded body, which is characterized by rapid high temperature curing at a temperature of 80 to 110°C. In the practice of the present invention, examples of the hydraulic cement include ordinary Portland cement, early strength Portland cement, moderate heat Portland cement, sulfate-resistant Portland cement, white Portland cement, blast furnace cement, silica cement, fly ash cement, and the like. Fine aggregates include river sand, crushed sand, silica sand, artificial lightweight sand, etc., and these are used in an appropriate amount of 0 to 100 parts by weight of cement, and in the case of mortar and concrete products, 100 to 300 parts by weight. use River gravel and crushed stone are commonly used as coarse aggregates, and are not added when making mortar molded products, but when producing concrete molded products, they are mixed at a ratio of 200 to 400 parts by weight, and the fine aggregate ratio is 27 It is commonly used in proportions of ~45% by weight. Water is added in an amount necessary for the hydration reaction of the cement, and in an amount that maintains the fluidity of the cement mixture so that it can easily be poured into a mold. Conventionally, when aiming at concrete molded products, water was mixed so that the cement mix had a slump value of 5 or more in order to obtain a product with a smooth surface.
In the present invention, a specific admixture is blended, and the cement mixture has excellent thixotropic properties, so even if the slump value is 0, if the formwork is vibrated after pouring into the formwork, the surface will be A smooth concrete molded product can be obtained. Next, we will discuss the cement admixture components. Examples of the sulfate of component (a) include sulfates of Al, Li, Tl, and Ga, and double salts thereof, such as NH 4 AlSO 4 . These sulfates and sulfate double salts can be used in either anhydrous or hydrated form, and can also be used in powder form or aqueous solution. Sulfates such as CaSO 4 , K 2 SO 4 , and Na 2 SO 4 are also commonly used as cement admixtures.
When CaSO 4 or Na 2 SO 4 is used, the compressive strength of the cement molded product immediately after demolding is low, and K 2 SO 4
When using steam curing conditions of 80°C or higher, products with high compressive strength can be obtained, but only cracked products can be obtained. Next, the oxycarboxylic acid or its metal salt as component (b) to improve the fluidity of the cement mixture includes gluconic acid, citric acid, tartaric acid, salicylic acid, or their Na, Li, K, Sr, Ca salts, etc. can be given. In particular, gluconic acid, citric acid, tartaric acid, salicylic acid, or their Na and K salts,
It is particularly effective in improving the fluidity of cement compositions than succinic acid, malic acid, glycolic acid, lactic acid, or their metal salts. As the alkali metal carbonate of component (c),
Examples include Na 2 CO 3 , K 2 CO 3 and Li 2 CO 3 . This carbonate addition serves to improve the compressive strength of cement moldings and the flowability of cement formulations. The composition of the admixture is: 0.01 to 0.7 parts by weight of oxycarboxylic acid or its salt as component (b) per 1 part by weight of sulfate as component (a), and 4 parts by weight or less of carbonate as component (c). Use at a ratio of In addition, the admixture is cement
1 to 20 parts by weight, preferably 3 parts by weight per 100 parts by weight
It is used in a proportion of ~15 parts by weight. Use of a large amount of admixture is undesirable because it reduces the mechanical strength of the resulting cement molded product. In addition to these admixtures, resin fillers, pigments, water reducing agents, air entraining agents (AE agents), thickeners, etc. can be added to the cement composition as necessary. Conventionally, AE agents were thought to be unfavorable for high-temperature curing because they increase the amount of air in concrete, but when used in combination with the specific sulfates and double sulfates of the present invention, they increase the air content of concrete. No foaming or expansion was observed in the internal structure, and good surface texture and structure were obtained. This is presumably because a skeleton is formed at the early stage of curing, and this skeleton acts in the direction of suppressing expansion, so that no thermal expansion of the air entrained by the AE agent occurs. in any case,
In the method of the present invention, the AE agent can be used without fear of expansion phenomenon, and the inherent effects of the AE agent can be fully exhibited, so that freeze-thaw resistance can be improved. The above hydraulic cement, specific sulfates, sulfate double salts, oxycarboxylate salts, water and aggregates (one or both of fine aggregates such as sand and coarse aggregates such as gravel and crushed stone),
Further, if necessary, other admixtures such as accelerators, retardants, water reducers, carbonates, etc. are added and kneaded, and the mixture is poured into molds and filled (cast), and then heated to 80℃ or higher at a rate of 40℃/hour or higher. Increase the temperature and add this hydraulic cement mixture to 1 to 3
Rapid high-temperature curing at a temperature of 80℃ or more under atmospheric pressure for an hour. After pouring, a pre-curing period may be allowed at room temperature, but in order to increase the production cycle of cement moldings, the temperature is rapidly raised immediately after pouring without pre-curing. The heating rate is 40° C./hour or more, preferably 60 to 120° C./hour, and within this rate range, no adverse effects are caused on the cement molded product obtained. The curing time should be at a high temperature of 80℃ or higher, preferably
It is sufficient to maintain a high temperature of 90 to 110°C for 15 to 60 minutes.
When performing high temperature curing over 100℃, an airtight curing device is required. For example, if you wrap the molded body in a sheet and ventilate it with pressurized steam, the
Can be cured at high temperatures exceeding ℃. As a heating medium for high-temperature curing, high-temperature pressurized steam used in general steam curing is suitable. Other heat curing methods, such as electric curing,
Electric heat curing, high frequency curing, heated air curing, and infrared heating curing can also be used without any problems. The cement molded body is immediately demolded after the above-mentioned high-temperature curing, and all manufacturing steps are completed. In order to increase the thermal efficiency of curing, it is effective to allow it to cool naturally (soaking) for a period of time (10 minutes to 2 hours). In this way, the cement molded product (cement, mortar or concrete product) obtained after a curing time of 1 to 3 hours has no defects such as swelling, foaming, or cracks on the surface and internal structure of the product, and has undergone necessary and sufficient demolding. It has high strength (100-200Kg/cm), and the increase in strength after demolding is the same as that of ordinary steam-cured products. In the practice of the present invention, component (a), sulfate or sulfate double salt, has the effect of suppressing expansion, foaming, and cracking of the hydraulic cement mixture and promoting hardening during rapid high-temperature curing of the cement mixture. It seems that this is what is being done. According to the method of the present invention, since the hydraulic cement mixture has excellent thixotropic properties, it is easy to cast into the mold, and a compressive strength of 80 kg/cm 2 or more can be obtained immediately after demolding in an extremely short time. This method has the advantage that cement molded products with smooth surfaces can be manufactured using open molds under atmospheric pressure. In addition, unlike the conventional high-temperature and high-pressure curing method, the method of the present invention does not require securing a large steam pressure in the compartment, so there is no need to attach special pressure-maintaining means to the curing equipment, and the conventional normal pressure curing method Steam curing equipment can be used as is. As for the formwork, there is no need to use a closed formwork that requires high equipment and operating costs, and a normal open formwork can be used as is. In other words, according to the present invention, rapid high-temperature curing can be safely performed without fear of expansion, which solves the problems of early strength development, shortening curing time, and increasing production cycles, while reducing equipment costs for formwork and curing equipment. This can be easily achieved without causing an excessive increase in operating costs, and in terms of the quality of the molded product itself, it is possible to reduce the pore volume in relatively large pore radii and improve freeze-thaw resistance. It has an improvement effect such as suppressing carbonation and suppressing carbonation. Next, Tables 1 to 5 show Examples and Comparative Examples of the present invention in which hydraulic cement mixtures were steam-cured by changing the type of admixture, amount added, and curing temperature.
It is organized and shown in the table. Example 1 100 parts by weight of ordinary Portland cement, standard sand
A cement mixture was prepared by adding the admixtures shown in Table 1 to 200 parts by weight and 60 parts by weight of water in the proportions shown in the table, and the change in flow value of this cement mixture over time was measured. The results are shown in the same table. Next, these cement mixtures were filled into an open steel formwork while the flow value was 130 mm or more, and after degassing by applying vibration to the formwork, the temperature was raised from 30°C to 90°C over 1 hour. and steam curing at 90℃.
After 60 minutes, the steam was turned off, the cement molded product was immediately demolded, and its appearance was examined. Judging the appearance is
The entire molded body was visually observed for expansion, foaming, the presence, size, and number of cracks.
【表】【table】
【表】
実施例 ２
実施例１のNo.７において、セメント100重量部
に対する酒石酸ソーダとNa2CO3の配合量を表２
のように変更して調製したセメント配合物のフロ
ー値の経時変化（５分後、20分後、30分後）を表
２に示す。なお、他の成分は次の通りである。
普通ポルトランドセメント 100部
標準砂 200部
水 60部
Al2（SO4）3・18H2O ６部[Table] Example 2 Table 2 shows the blending amounts of sodium tartrate and Na 2 CO 3 for 100 parts by weight of cement in No. 7 of Example 1.
Table 2 shows the change in flow value over time (after 5 minutes, after 20 minutes, after 30 minutes) of the cement mixture prepared with the following changes. In addition, other components are as follows. Ordinary Portland cement 100 parts Standard sand 200 parts Water 60 parts Al 2 (SO 4 ) 3・18H 2 O 6 parts
【表】【table】
【表】
実施例 ３
実施例１のNo.７において、セメント100重量部
に対する酒石酸ナトリウムと炭酸ナトリウムの配
合量を表３のように変更して調整したセメント配
合物（モルタル）のフロー値の経時変化を表３に
示す。なお、他の成分は次の通りである。
普通ポルトランドセメント 100部
標準砂 200部
水 48部
Al2（SO4）3・18H2O ３部[Table] Example 3 Flow value over time of cement mixture (mortar) prepared by changing the blending amounts of sodium tartrate and sodium carbonate to 100 parts by weight of cement as shown in Table 3 in No. 7 of Example 1 The changes are shown in Table 3. In addition, other components are as follows. Ordinary Portland cement 100 parts Standard sand 200 parts Water 48 parts Al 2 (SO 4 ) 3・18H 2 O 3 parts
【表】【table】
【表】
実施例 ４
普通ポルトランドセメント100重量部、標準砂
200重量部、水45重量部に対し、表４に示す混和
剤を配合してセメント配合物を調製し、これを混
練後、15分後に開放鋼製型枠内に打設し、以下、
実施例１と同様に昇温、蒸気養生して脱型し、セ
メント成型品を得た。
このセメント成型品の脱型直後の外観、圧縮強
度、曲げ強度を表４に示す。[Table] Example 4 100 parts by weight of ordinary Portland cement, standard sand
A cement mixture was prepared by blending the admixtures shown in Table 4 with 200 parts by weight and 45 parts by weight of water, and after kneading this, 15 minutes later, it was poured into an open steel form.
As in Example 1, the mixture was heated, steam-cured, and demolded to obtain a cement molded product. Table 4 shows the appearance, compressive strength, and bending strength of this cement molded product immediately after demolding.
【表】
実施例 ５
普通ポルトランドセメント18Kg、川砂33Kg、砂
利61Kg、水6.8Kgに表５に示す混和剤を、セメン
トに対し同表に示す割合で配合したセメント配合
物を調製し、混練後、15分で開放鋼製型枠内に打
設し、60℃／時間の昇温速度で95℃迄昇温後、同
温度で60分、蒸気養生し、蒸気を止めた。
ついで、15分、放冷後、直にコンクリート成型
品を脱型し、外観と圧縮強度を測定した。
結果を表５に示す。[Table] Example 5 A cement mixture was prepared by mixing 18 kg of ordinary Portland cement, 33 kg of river sand, 61 kg of gravel, and 6.8 kg of water with the admixtures shown in Table 5 in the ratios shown in the table to the cement, and after kneading, It was poured into an open steel formwork in 15 minutes, heated to 95°C at a heating rate of 60°C/hour, steam-cured at the same temperature for 60 minutes, and then the steam was turned off. After cooling for 15 minutes, the concrete molded product was immediately demolded and its appearance and compressive strength were measured. The results are shown in Table 5.
【表】【table】
【表】
＊ セメントに対する配合割合
[Table] * Mixing ratio to cement
Claims (1)
粗骨材０重量部〜適量、水適量および下記の組成
割合の混和剤１〜20重量部 (a) リチウム、アルミニウム、ガリウム、タリウ
ムの硫酸塩またはそれらの金属を含む硫酸複塩
の１種または２種以上の硫酸塩 １重量部 (b) オキシカルボン酸またはその塩
0.01〜0.7重量部 (c) アルカリ金属の炭酸塩 ０〜４重量部 の割合で配合された水硬性セメント配合物を型枠
に打設し、これを40℃〜120℃／時間の昇温速度
により80℃〜110℃の温度で急速高温養生するこ
とを特徴とするセメント成型体の製造方法。 ２ 水硬性セメント配合物を型枠に打設した後、
90℃〜110℃の養生温度に致らしめる昇温速度が
60℃〜120℃／時間であることを特徴とする特許
請求の範囲第１項記載のセメント成型体の製造方
法。 ３ 硫酸塩が硫酸アルミニウムの水和物であるこ
とを特徴とする特許請求の範囲第１項記載のセメ
ント成型体の製造方法。 ４ オキシカルボン酸またはその塩が、グルコン
酸、酒石酸、クエン酸、サリチル酸またはこれら
酸のアルカリ金属塩であることを特徴とする特許
請求の範囲第１項記載のセメント成型体の製造方
法。 ５ 水硬性セメント配合物を型枠に充填後、前養
生なしで急速高温養生を行うことを特徴とする特
許請求の範囲第１項または第２項記載のセメント
成型体の製造方法。 ６ セメント100重量部に対する細骨材の配合割
合が100〜300重量部で、粗骨材の配合割合が200
〜400重量部であることを特徴とする特許請求の
範囲第１項記載のセメント成型体の製造方法。[Claims] 1. 100 parts by weight of cement, 0 parts by weight to appropriate amount of fine aggregate,
0 to 20 parts by weight of coarse aggregate, an appropriate amount of water, and 1 to 20 parts by weight of an admixture with the following composition ratio (a) One or more sulfates of lithium, aluminum, gallium, thallium, or double sulfate salts containing these metals. Two or more sulfates 1 part by weight (b) Oxycarboxylic acid or its salt
0.01 to 0.7 parts by weight (c) Alkali metal carbonate A hydraulic cement mixture mixed in a proportion of 0 to 4 parts by weight is poured into a formwork, and heated at a heating rate of 40°C to 120°C/hour. A method for producing a cement molded body, characterized by rapid high-temperature curing at a temperature of 80°C to 110°C. 2 After pouring the hydraulic cement mixture into the formwork,
The heating rate to reach the curing temperature of 90℃ to 110℃ is
The method for producing a cement molded body according to claim 1, characterized in that the temperature is 60°C to 120°C/hour. 3. The method for producing a cement molded body according to claim 1, wherein the sulfate is a hydrate of aluminum sulfate. 4. The method for producing a cement molded body according to claim 1, wherein the oxycarboxylic acid or its salt is gluconic acid, tartaric acid, citric acid, salicylic acid, or an alkali metal salt of these acids. 5. A method for producing a cement molded body according to claim 1 or 2, characterized in that after filling a formwork with a hydraulic cement mixture, rapid high-temperature curing is performed without pre-curing. 6 The blending ratio of fine aggregate to 100 parts by weight of cement is 100 to 300 parts by weight, and the blending ratio of coarse aggregate is 200 parts by weight.
The method for producing a cement molded body according to claim 1, wherein the amount is 400 parts by weight.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14904283A JPS6042263A (en) | 1983-08-15 | 1983-08-15 | Manufacture of cement moldings |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14904283A JPS6042263A (en) | 1983-08-15 | 1983-08-15 | Manufacture of cement moldings |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6042263A JPS6042263A (en) | 1985-03-06 |
| JPH0155212B2 true JPH0155212B2 (en) | 1989-11-22 |
Family
ID=15466374
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP14904283A Granted JPS6042263A (en) | 1983-08-15 | 1983-08-15 | Manufacture of cement moldings |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6042263A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007254987A (en) * | 2006-03-22 | 2007-10-04 | Sumitomo Osaka Cement Co Ltd | Method of improving fluidity of grout material using low-heat portland cement |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2548379B2 (en) * | 1989-06-08 | 1996-10-30 | 電気化学工業株式会社 | Super quick hardening cement composition |
| JPH11116306A (en) * | 1997-10-14 | 1999-04-27 | Denki Kagaku Kogyo Kk | Cement admixture and cement composition containing the same |
| JP2001048616A (en) * | 1999-08-11 | 2001-02-20 | Yoshiro Wakimura | Cement accelerator and cement |
| JP2002087867A (en) * | 2000-09-11 | 2002-03-27 | Nissan Chem Ind Ltd | Method of manufacturing cement material |
| JP4745259B2 (en) * | 2007-02-02 | 2011-08-10 | 電気化学工業株式会社 | Cement composition |
| JP7122170B2 (en) * | 2018-06-18 | 2022-08-19 | デンカ株式会社 | Curing accelerator for concrete surface finish |
| JP7173827B2 (en) * | 2018-10-23 | 2022-11-16 | デンカ株式会社 | Ultra fast-hardening composition, cement composition, concrete composition and spraying method |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS48102829A (en) * | 1972-03-09 | 1973-12-24 | ||
| JPS5318047A (en) * | 1976-07-30 | 1978-02-18 | Sulzer Ag | Heat exchanger having wall separator for both media in heat exchange |
-
1983
- 1983-08-15 JP JP14904283A patent/JPS6042263A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS48102829A (en) * | 1972-03-09 | 1973-12-24 | ||
| JPS5318047A (en) * | 1976-07-30 | 1978-02-18 | Sulzer Ag | Heat exchanger having wall separator for both media in heat exchange |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007254987A (en) * | 2006-03-22 | 2007-10-04 | Sumitomo Osaka Cement Co Ltd | Method of improving fluidity of grout material using low-heat portland cement |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6042263A (en) | 1985-03-06 |
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