CSA expansive additive description:

The CSA expansive additive is obtained by blending natural anhydrite with clinker powder which consists of calcium sulfoaluminate and CaO. This CSA expansive additive is always mixed with ordinary cement. When mixed in the proper proportion with ordinary cement and hydrated, cement mortar or concrete expands during the early stages of hydration. It is developed to reduce and compensate the hydraulic shrinkage of cement based construction products. Its performance is similar to Denka CSA #20, which is now widely used in the formulation of different mortars in Europe countries.

As a fire brick supplier, we offer two types of these CSA expansive additives, the main specifications are according to JC476-2001

CSA expansive additive technical data:

Parameters CSA Expansive additive I CSA Expansive additive II

MgO % ≦ 5.0 ≦ 5.0

Water content % ≦ 3.0 ≦ 3.0

Total Alkali % ≦ 0.75 ≦ 0.75

Chloride ion % ≦ 0.05 ≦ 0.05

Specific Surface Area ≧200m2/kg ≧200m2/kg

Fineness 1.18mm residue ≦ 12 ≦ 12

Setting time Initial setting time ≧ 0:45 ≧ 0:45

Final setting time ≦ 10:00 ≦ 10:00

Limited Expansive Rate (%) 7 days in water ≧0.025 ≧0.05

21 days in air ≧-0.020 ≧-0.010

Compressive strength

（MPa） 7days ≧25 ≧25

28days ≧45 ≧45

Bending strength

（Mpa） 7days ≧4.5 ≧4.5

28days ≧6.5 ≧6.5

CSA expansive additive performance:

(1) As making shrinkage compensated concrete, if the ratio of reinforcement is 0.2%-1.0%, the limited expansive rate will be in the range of 0.02-0.04%, and a prestress of 0.2-0.7Mpa exists in the concrete.

(2) Comparing with the concrete without Expansive Additive, in the condition of defined mixing amount, the free strength of the concrete with Expansive Additive is roughly equal to that of concrete without Expansive Additive. The limited strength is 10~15% higher than free strength.

(3) The impermeability grade of mortar and concrete can reach over S30. The elastic ratio closes to that of common concrete.