MasterMatrix UW 440 - Anti-wash out admixture for use in underwater concrete or piling applications

How does MasterMatrix UW 440 work?

MasterMatrix UW 440 anti-washout admixture is a ready to use, powdered admixture specially developed for concrete placed underwater. Concrete treated with MasterMatrix UW 440 exhibits superior resistance to washout of cement and fines.
MasterMatrix UW 440 complies with BS 8443:2005 – “Specification for establishing the suitability of special purpose concrete admixtures” - Table 2 - Underwater Concrete Admixtures.
MasterMatrix UW 440 can also be used, at a lower dosage rate, in piling applications to prevent poor surrounding ground conditions from absorbing moisture from the concrete mix, and therefore making post pouring operations such as placing the reinforcing cage easier.

MasterMatrix UW 440 admixture is recommended for use in all types of concrete pumped or placed underwater, where thixotropic action is desired. MasterMatrix UW 440 admixture is especially helpful in extreme conditions where conventional concrete or placing techniques would result in a high percentage of material loss due to washout.
Piling operations in poor ground conditions, or where a deep reinforcing cage needs to be inserted after the completion of the concrete placement.

What are the unique features of MasterMatrix UW 440?

MasterMatrix UW 440 admixture produces a concrete mixture highly resistant to washout, while maintaining workability, pumpability, and placeability.

What are the benefits of MasterMatrix UW 440?

  • Minimal to no effect on water demand.
  • Reduces or eliminates concrete bleeding.
  • Workability characteristics equal to untreated concrete.
  • Virtually eliminates segregation even with highly fluid, high water-cementitious ratio mixes.
  • Reduces/eliminates costly methods of de-watering.
  • Thixotropic action provides stiffening after concrete is placed.
  • Minimises environmental impact of cement washout in water.
  • Minimal to no effect on set time.
  • Prevents absorption of moisture from the concrete into surrounding ground during piling operations.
  • Easier placement of deep section reinforcing cages. 


MasterMatrix UW 440 Safety Data Sheet Australia

pdf (53.74 Kb)

MasterMatrix UW 440 Technical Data Sheet

pdf (150.66 Kb)