The world’s best shrinkage compensating cement additive.
Since 1968, Demden has been supplying Denka CSA to a variety of NZ concrete product manufacturers and construction projects. That’s over 40 years of proven results.
Denka CSA (Calcium Sulpho Aluminate) is an Expansive Cement Additive used to chemically pre-stress concrete, providing compensation for drying shrinkage, and reducing or even completely eliminating shrinkage cracks.
Create large concrete slabs with fewer construction joints and without saw cuts. In fact, Denka CSA has been successfully used to construct joint-free single slabs of up to 3080m2 (65m x 60m) in New Zealand.
Denka CSA is particularly useful in large warehouses with high level racking. The result is greater durability and less damage from forklift traffic.
Denka CSA is always mixed with Type GP Portland cement, in correct proportions.
As the resulting concrete is curing and gaining strength, it expands. Bonded to the steel, this expanding concrete causes the steel to be stretched slightly, placing it in tension. As drying shrinkage takes place, the steel is relieved.
When the ratio of Denka CSA to cement is increased, its high expansion qualities make it ideal for use in pre-stressed concrete.
Specifications and reinforcing guidelines are available on request.
Demden are New Zealand’s exclusive suppliers of Denka CSA.