Polycarboxylate superplasticizer is an internationally advanced 3rd generation superplasticizer. It has the characteristics of low dosage, high water-reducing rate, significant enhancement effect, and good cement adaptability. The set-retarding PCA-R polycarboxylate superplasticizer for railway construction is a concrete additive developed specially for railway concrete engineering in accordance with CRCC certification, which can meets both the requirement of “Polycarboxylate Superplasticizer” in GB8076-2008 Concrete Additive standard and the performance requirement of “Polycarboxylate Superplasticizer” in TB/T3275-2011 Railway Concrete.
Major Technical Features
1. Properties and solid content: The product is liquid(water agent); the regular solid content is 26%.
2. Stable chemical properties, no precipitation of water, and no crystallization in winter. After long resting (more than one week), it should be stirred even before use.
3. Fluidity of cement paste≥230mm (when dosage of liquid polycarboxylate superplasticizer converted into solid is 1%).
4. Low dosage. The regular dosage is about 1.0% of the weight of cement material.
5. Air content≤3.0%; PH value 6.0~7.0
6. High performance of reducing water. When the dosage is 1.0%, the water reducing rate can reach 25%. It can be used to prepare high strength concrete, high performance concrete, and high fluidity of concrete with slump loss of more than 200mm.
7. Good cement dispersion and good cement adaptability
8. The compressive resistance ratio of concrete at different stages is higher than the requirement “set-retarding type of high performance water reducer” in GB8076-2008 and TB/T3275-2011
9. The setting time is generally controlled to the range 15±5h. It can be prepared according to the user’s requirement.
10. Small concrete shrinkage, which can reduce the cracking of concrete.
11. Low alkali content, which will not lead to the occurrence of alkali aggregate reaction.
12. It causes no corrosion to iron in concrete
13. It is effective in slump retention, with little slump loss of concrete. It has obvious effect in inhibiting concrete slump loss.
14. Other indexes meet the standard of GB8076-2008 and TB/T3275-2011
Major Applications
1. It is dedicated to railway concrete engineering.
2. It can be used to prepare liquid concrete with slump loss of more than 200mm , precast concrete and pumped concrete.
3. It can be used to prepare high performance concrete of strength ≤C100
4. It can be used for vibration-free self compacting concrete for special engineering.
Use and Cautions
1. The regular dosage of the liquid is 1.0% of the weight of cement material. The specific dosage is determined according to the grade of concrete strength, on-site material and construction conditions after test.
2. The dosage accuracy error of admixture shall not be greater than 1.0%.
3. The product is packed in bucket, 50kg or 200kg per bucket, or transported by tank car. In transportation and storage, attention shall be paid to rainproofing, waterproofing and dampproofing.
4. The shelf life of the product is 3 months; expired products should be tested before use
5. The product cannot be mixed with naphthalene series water reducer, aliphatic water reducer and amino water reducer.
6. The product should be subjected to concrete performance test before use.
