Xypex Admixtures - Seven Unique Features

Xypex Australia has answered seven questions commonly asked by Specifiers about its unique crystalline technology admixtures.


Q1:  Are all crystalline additives the same?

All “crystalline additives” available in the market might appear similar to each other in the bag, however there is significant variation in terms of chemical composition under XRF (X-ray Fluorescence Analysis) and most importantly performance compliance to Australian Standard AS1478.1 - Chemical Admixtures for Concrete.

- Environmental Preferability

Xypex Admix C-1000NF and Admix C-5000 are endorsed by Good Environmental Choice Australia (GECA) as environmentally preferable and therefore meet the requirements of Green Star Ratings in accordance with the Green Building Council of Australia.

The certification as a good ‘environmental choice’ means that Admix C-1000NF and Admix C-5000  comply with the environmental and social performance characteristics as detailed in the voluntary environmental labelling standard - Innovative Products.
 

- Reduced Environmental Load

The GECA certification endorses Xypex Admix C-1000NF and C-5000 as having design and manufacturing attributes which directly reduce the environmental load by at least 30% when compared to similar concrete waterproofing & protection products available on the Australian market. Further Information >

Q2:  Is the ‘sorptivity test’ the best test for concrete durability?

Sorptivity is not the best test for durability. It is only part of a number of tests available for durability assessment. Project objectives and conditions would determine the suitable durability test in the service life assessment. For example, a chloride diffusion test would be more suitable for a marine project where chloride ingress protection is required.

Other durability testing methods include water permeability and accelerated chloride diffusion tests.

Please visit our Technical section on the Xypex Australia web site for a downloadable shortform specification, which outlines suitable durability tests for “crystalline additive products”.


Q3: Does Xypex give off an odour or provide any OH&S issues?

Xypex does not give off an odour or provide any OHS issues. Xypex products also comply with Australian Standards AS4020: Products for use in contact with drinkable water. Please visit the Technical Section on the Xypex Australia web site for downloadable compliance certificates.


Q4: Does Xypex crystalline additive comply with Australian Standards?

Xypex Crystalline Admixture C-Series complies with Australian Standard AS 1478.1, Appendix F – Chemical Admixture for Concrete, Mortar, and Grout as Type SN (special purpose neutral set admixture). Please visit Technical Section on Xypex Australia official web site for downloadable compliance certificates.


Q5: Is Xypex Admix suitable for potable water?

Xypex products comply with Australian Standards AS4020: Products for use in contact with drinkable water. Please visit Technical Section on Xypex Australia official web site for downloadable compliance certificates.


Q6: Can Xypex Admix be used with a concrete mix containing SCM’s?

Xypex Admix has been tested and proven and is compatible with concrete mix design with inclusion of Supplementary Cementitious Materials (Fly Ash, GGBS, Silica Fume). Information on properties of concrete modified with Xypex Admix is available upon request or please visit the Xypex Australia website for details.


Q7:   How does Xypex compare with other admixtures in the market?

Penetrability-reducing admixtures form a new class of chemical admixtures that can reduce the rate of transmission of moisture either in a liquid or vapour form through concrete. It is the moisture transportation that plays an important role as a vehicle carrying chlorides and other aggressive ions into concrete through the pore system.

Several types of penetrability-reducing admixtures are commercially available. Some of these are classified as hydrophobic admixtures due to the presence of long-chained fatty acids or vegetable oils. These tend to have more effect on absorption than permeability; therefore they are not suitable for concrete structures subjected to hydrostatic pressure.

Xypex Admix C-Series is classified as a microstructure modifier which reduces concrete permeability through crystallisation activity in concrete pores.  It has the ability to greatly reduce water penetration and also impart good resistance to chemical attack in concrete.

Xypex Admix C-Series is a permeability-reducing admixture characterised by crystallization reactivity and is an inorganic admixture. The active ingredients in Xypex react with a broad range of hydration by-products which include various metal oxides and salts, unhydrated and partially hydrated cement particulates as well as calcium hydroxide, regardless of the Portland or blended cement types. The reactive products of Xypex Admix are in mineral crystal form and grow in the residual vacancies (pores and cracks) in concrete, with a unique ability to self-heal hairline cracks up to 0.4mm.

For further information on the Xypex range of products please contact us.