High-efficiency CSA Expansive Agent

Product Description

General description
              
High-efficiency CSA Expansive Agent is obtained by blending suitable natural anhydrite with a specially manufactured clinker which consists essentially of calcium sulphoaluminate and CaO. High-efficiency CSA expansive agent is always mixed with ordinary cement. When mixed in the proper proportions with ordinary cement and hydrated, cement mortar or concrete expands during the early stages of hydration. This expansion, when restrained, makes it possible to minimize drying shrinkage. Moreover, when the ratio of High-efficiency CSA Expansive Agent to ordinary cement is increased its high expansion qualities make it ideal for use in prestressed concrete.
High-efficiency CSA Expansive Agent is being used in all sections of the construction fields and by a wide variety of concrete products manufacturers.
High-efficiency CSA Expansive Agent is manufactured under a strict quality assurance systems GB/T *********0 (i.e. ISO***1:***0) and GB/T *********6 (i.e. ISO ****1:***6)) which accommodates the technical requirements of building chemistry formulators.
The properties of High-efficiency CSA Expansive Agent conform to the standards of the manufacturer and to the Chinese relevant standards.
Characteristics of High-efficiency CSA Expansive Agent   
●     Low alkalinity.
●     High-efficiency CSA Expansive Agent has a very low alkali content (R2O Mineral Composition: CaO, CaSO4, 3CaO·3Al2O3 ·CaSO4.
Specific Surface Area: **0~**0 m2/kg.
Specific Gravity: 2.8~3.0.
Physical Properties 
The restrained expansion rate tested under standard condition: Dosage in OPC (%) Restrained-expansion rate (%) Curing 7d in water Curing 7d in water then *1d in air TypeⅠ,7 0.****0.**0 ≥0 TypeⅡ,7 0.****0.**5      ≥*0.**5 TypeⅡ,*0 0.****0.**0 ≥0  
The effect of High-efficiency CSA Expansive Agent dosage on strength of cement mortar:
Longitudinal change of mortar:
Directions for Use
1. Dosage
High-efficiency CSA Expansive Agent is used as a part of cement, its proportion to ordinary Portland cement depends upon the intended use and the degree of restraint. The proportion of High-efficiency CSA Expansive Agent to ordinary cement generally used in China is about 6~8%. 
2. Mixing
High-efficiency CSA Expansive Agent and ordinary cement must be thoroughly and uniformly mixed in a mechanical mixer with aggregate and water for a slightly longer time than normal concrete. 
3. Curing
To ensure the proper development of the ettringite needle crystals which are important in preventing shrinkage cracks which occur during drying period, it is recommended that water be sprayed or membrane curing onto the concrete surface for curing at least *4 days after the concrete is cast.
4. Storage
High-efficiency CSA Expansive Agent is more sensitive to water and moisture than other cementitious material and is therefore packed in completely waterproof bags and should always be kept and stored in a dry place.