混凝土外加劑的種類/Types of concrete admixtures

外加劑的作用與使用效果歸納

1.普通減水劑

品種：木質素磺酸鹽類：木質素磺酸鈣、木質素磺酸鈉、木質素磺酸鎂、丹寧等

主要功能

① 在保持單位立方混凝土用水量和水泥用量不變的情況下，提高混凝土的流動性；

② 在保持混凝土坍落度和水泥用量不變的情況下，可減少用水量，從而提高混凝土的強度，改善混凝土的耐久性；

③ 在保持混凝土坍落度和設計強度不變的情況下，可節約水泥用量，從而降低成本；

④ 在保持混凝土坍落度不變的情況下，通過配合比設計，可達到同時節約水泥用量和提高混凝土強度的目的；

適用范圍

① 普通減水劑及高效減水劑可用于素混凝土、鋼筋混凝土、預應力混凝土，并可制備高強度性能混凝土；

② 普通減水劑宜用于日最低氣溫5℃以上施工的混凝土，不宜用于蒸養混凝土

2.高效減水劑

（1）品種

① 多環芳香族磺酸鹽類：萘和萘的同系磺化物與甲醛縮合的鹽類、氨基磺酸鹽等；

② 水溶性樹脂磺酸鹽類：磺化三聚氰胺樹脂、磺化古馬隆樹脂等；

③ 脂肪族類：聚羧酸鹽類、聚丙烯酸鹽類、脂肪族羥甲基磺酸鹽高縮物等；

④ 其他：改性木質素磺酸鈣、改性丹寧等。

3.早強劑及早強減水劑

（1）品種

① 強電解質無機鹽類早強劑：硫酸鹽、硫酸復鹽、硝酸鹽、亞硝酸鹽、氯鹽等；

② 水溶性有機化合物：三乙醇胺、甲酸鹽、乙酸鹽、丙酸鹽等；

③ 其他：有機化合物、無機鹽復合物。

有堿活性的混凝土結構時，由外加劑帶入的堿含量不宜超過1kg/m3混凝土，混凝土總堿含量應符合有關標準規定。

4.緩凝劑及緩凝減水劑

（1）品種

① 糖類：糖鈣、葡萄糖酸鹽等；

② 木質素磺酸鹽類：木質素磺酸鈣、木質素磺酸鈉；

③ 羥基羧酸及其鹽類：檸檬酸、酒石酸鉀鈉等；

④ 無機鹽類：鋅鹽、磷酸鹽等；

⑤ 其他：銨鹽及其衍生物、纖維素醚等。

5.引氣劑及引氣減水劑

（1）品種

① 松香樹脂類：松香熱聚物、松香皂類等；

② 烷基和烷基芳烴磺酸鹽類：十二萬基磺酸鹽、烷基苯磺酸鹽、烷基苯酚聚酸鈉等；

③ 脂肪醇磺酸鹽類：脂肪醇聚氧乙烯醚、脂肪醇聚氧乙烯磺酸鈉、脂肪醇硫酸鈉等；

④ 皂甙類：三萜皂甙等；

⑤ 其他：蛋白質鹽、石油磺酸鹽等。

6.防凍劑

（1）品種

① 強電解質無機鹽：包括氯鹽類、氯鹽阻銹類無氯鹽類；

② 水溶性有機化合物類:以某些醇類等有機化合物為防凍組分的外加劑；

③ 有機化合物與無機鹽復合類；

④ 復合型防凍劑：以防凍組分復合早強、引氣、減少組分的外加劑。

7.膨脹劑

（1）品種

硫鋁酸鈣類；

② 硫鋁酸鈣-氧化鈣類；

③ 氧化鈣類

8.泵送劑

（1）品種

混凝土工程中，泵送劑可采用由減水劑、緩凝劑、引氣劑等復合而成。

（2）主要功能

除具有減水劑的作用外，還可以起到：

① 改善混凝土的泵送性；

② 減小混凝土坍落度經時損失；

（3）適用范圍

泵送劑適用于工業和民用建筑及其他構筑物的泵送施工的混凝土；特別適用于大體積混凝土，高層建筑和

超高層建筑；適用于滑模施工等場合；也適用于水下灌注樁混凝土。

9.防水劑

（1）品種

① 無機化合物類：氯化鐵、硅灰粉末、鎬化合物等；

② 有機化合物類：脂肪酸及其鹽類、有機硅表面活性劑、石蠟、地瀝青、橡膠及水溶性樹脂乳液等；

③ 混合物類：無機類混合物、有機類混合物、無機類和有機類混合物；

④ 復合類：上述各類與引氣劑、減水劑、調凝劑等外加劑復合的復合型防水劑。

10.速凝劑

（1）品種

① 在噴射混凝土工程中可采用的粉末狀速凝劑：以鋁酸鹽、餐酸鹽等為主要成分的無機鹽混合物等；

② 在噴射混凝土工程中可采用的液體速凝劑：以鋁酸鹽、水玻璃等為主要成分，與其他無機鹽復合而成的復合物。

（2）主要功能

11.阻銹劑

主要功能

① 阻止混凝土內部配筋和預埋金屬的銹蝕；

② 改善混凝土的耐久性。

12.粘結劑

主要功能

① 增強新老混凝土之間的粘結強度；

② 避免出現冷鋒；

③ 提高混凝土修補加固工程的質量等。

13.著色劑

主要功能

① 生產具有各種不同顏色的混凝土制品；

② 配制彩色砂漿；

③ 配制彩色水泥漿等。

14.水下澆筑混凝土抗分散劑

主要功能

① 提高新拌混凝土的粘聚性；

② 提高混凝土水下澆筑時的抗分離性；

③ 避免對混凝土澆筑區附近水域的污染等。

15.?脫模劑

主要功能

① 使混凝土易于脫模；

② 改善混凝土的表面質量等。

16.養護劑

主要功能

① 阻止混凝土內部水分蒸發；

② 提高混凝土養護質量；

③ 減少混凝土的干縮開裂；

④ 減少養護勞動力；

⑤ 滿足干燥炎熱氣候下的施工要求；

⑥ 改善混凝土的耐久性等。

17.堿-集料反應抑制劑

主要功能

① 預防混凝土內部堿-集料反應；

② 改善混凝土的耐久性等。

The effect and use effect of admixtures are summarized

1. Ordinary water reducer

Varieties: Lignosulfonates: calcium lignosulfonate, sodium lignosulfonate, magnesium lignosulfonate, tannin, etc

Main function

(1) Improve the fluidity of concrete while keeping the water consumption per cubic meter of concrete and the amount of cement unchanged;

In the case of keeping the slump of concrete and the amount of cement unchanged, the water consumption can be reduced, so as to improve the strength of concrete and improve the durability of concrete;

(3) Under the condition of keeping the slump of concrete and the design strength unchanged, the amount of cement can be saved, thus reducing the cost;

(4) Under the condition of keeping the slump of concrete unchanged, the purpose of saving the amount of cement and improving the strength of concrete can be achieved through the mix ratio design;

Scope of application

① Ordinary superplasticizer and high efficiency superplasticizer can be used for plain concrete, reinforced concrete, prestressed concrete, and can prepare high strength concrete;

② Ordinary superplasticizer should be used for concrete with daily minimum temperature above 5℃, and should not be used for steamed concrete

2. High efficiency water reducing agent

(1) Varieties

① Polycyclic aromatic sulfonates: naphthalene and naphthalene homologous sulfonates condensed with formaldehyde salts, sulfamate, etc.;

② Water-soluble resin sulfonates: sulfonated melamine resin, sulfonated gumarone resin, etc.;

(3) Fatty family: polycarboxylate, polyacrylate, aliphatic hydroxymethylsulfonate high shrinkage, etc.;

④ Others: modified calcium lignosulfonate, modified tannin, etc.

3. Early strength agent Early strength water reducer

(1) Varieties

① Strong electrolyte inorganic salts early strength agents: sulfate, sulfate compound salt, nitrate, nitrite, chlorine salt, etc.;

② Water-soluble organic compounds: triethanolamine, formate, acetate, propionate, etc.;

③ Other: organic compounds, inorganic salt complex.

When the concrete structure has alkali activity, the alkali content brought in by the admixture should not exceed 1kg/m3 concrete, and the total alkali content of concrete should comply with the relevant standards.

4. Retarding agent and retarding water reducer

(1) Varieties

① Sugar: sugar calcium, gluconate, etc.;

② Lignosulfonates: calcium lignosulfonate, sodium lignosulfonate;

③ hydroxy-carboxylic acids and their salts: citric acid, potassium sodium tartrate, etc.;

④ Inorganic salts: zinc salt, phosphate, etc.;

⑤ Others: ammonium salts and their derivatives, cellulose ether, etc.

5. Air entraining agent and air entraining water reducing agent

(1) Varieties

① Rosin resins: rosin hot polymers, rosin soap, etc.;

② Alkyl and alkyl aromatic sulfonates: 120 million base sulfonates, alkyl benzene sulfonates, alkyl phenol polysodium acid, etc.;

③ Fatty alcohol sulfonates: fatty alcohol polyoxyethylene ether, fatty alcohol polyoxyethylene sulfonate sodium, fatty alcohol sodium sulfate, etc.;

④ Saponins: triterpenoid saponins;

⑤ Others: protein salt, petroleum sulfonate, etc.

6. Antifreeze

(1) Varieties

(1) Strong electrolyte inorganic salts: including chlorine salts, chlorine-resistant rust, chlorine-free salts;

② Water-soluble organic compounds: additives with some alcohols and other organic compounds as anti-freezing components;

(3) Compound of organic compounds and inorganic salts;

(4) Compound antifreeze: admixtures with antifreeze components that combine early strength, bleed air and reduce components.

7. Expansion agent

(1) Varieties

Calcium sulfoaluminate;

② Calcium sulfoaluminate – calcium oxide;

③ Calcium oxide

8. Pumping agent

(1) Varieties

In concrete engineering, the pumping agent can be composed of water-reducing agent, retarder and air entraining agent.

(2) Main functions

In addition to the role of water reducing agent, it can also play:

① Improve the pumpability of concrete;

② Reduce concrete slump loss over time;

(3) Scope of application

The pumping agent is suitable for the pumping construction of industrial and civil buildings and other structures; Especially suitable for large volume concrete, tall buildings and

Supertall buildings; Suitable for slip-form construction and other occasions; It is also suitable for underwater cast-in-place pile concrete.

9. Water repellent

(1) Varieties

① Inorganic compounds: ferric chloride, silica powder, pick compounds, etc.;

② Organic compounds: fatty acids and their salts, silicone surfactants, paraffin, asphalt, rubber and water-soluble resin emulsions, etc.

③ Mixtures: inorganic mixtures, organic mixtures, inorganic and organic mixtures;

④ Composite class: the above types and air entrainment agent, water reducing agent, regulating agent and other admixtures of compound water repellent.

10. Accelerants

(1) Varieties

① The powder accelerator that can be used in the shotcrete project: inorganic salt mixture with aluminate and dinate as the main components;

② Liquid accelerator that can be used in shotcrete projects: aluminate, water glass, etc., as the main components, and other inorganic salts composite.

(2) Main functions

11. Rust inhibitor

Main function

① Prevent the corrosion of internal reinforcement and embedded metal in concrete;

② Improve the durability of concrete.

12. Binder

Main function

① Strengthen the bond strength between new and old concrete;

② Avoid cold front;

③ Improve the quality of concrete repair and reinforcement projects.

13. Colorant

Main function

① The production of concrete products with various colors;

② Preparation of color mortar;

③ Preparation of color cement slurry, etc.

14. Pour concrete anti-dispersant underwater

Main function

① Improve the cohesiveness of newly mixed concrete;

(2) Improve the separation resistance of concrete in underwater pouring;

③ Avoid the pollution of the water near the concrete pouring area.

15. Release agent

Main function

① Make concrete easy to demoulding;

② Improve the surface quality of concrete.

16. Curing agent

Main function

① Prevent the evaporation of water inside the concrete;

② Improve the curing quality of concrete;

③ Reduce the dry shrinkage cracking of concrete;

④ Reduce the maintenance labor force;

⑤ Meet the construction requirements in dry and hot climates;

⑥ Improve the durability of concrete.

17. Alkali-aggregate reaction inhibitors

Main function

① Prevent alkali-aggregate reaction in concrete;

② Improve the durability of concrete.