AS NZS 3582.3:2002 pdf download.Supplementary cementitious materials for use with portland and blended cement Part 3: Amorphous silica.
3 DEFINITIONS
For the purpose of this Standard, the definitions below apply.
3.1 Amorphous silica
A very fine pozzolanic material composed mostly of non-crystalline silica.
NOTE: The materials may contain some crystalline silica and individual suppliers should be contacted for detailed information if required.
3.2 Naturally occurring amorphous silica
A refined pozzolanic material, composed mostly of amorphous silica derived either from hydrothermal alteration of ignimbrite and pumice breccia or from the extraction of precipitated silica from geothermal water.
3.3 Pozzolan
A siliceous or siliceous and aluminous material which is not naturally cementitious, but will, in the presence of moisture, react with calcium hydroxide to form cementitious corn pounds.
3.4 Silica fume
A very fine pozzolanic material, composed mostly of amorphous silica produced by electric
arc furnaces as a by-product of the production of elemental silicon or ferro-silicon alloys.
4 PHYSICAL FORMS OF AMORPHOUS SILICA
The physical forms of amorphous silica that may be encountered are as follows:
(a) Silica fume
(i) Undens/Ied Undensified silica fume taken directly from the collection filter may have a bulk density typically less than 400 kg/rn3.
(ii) Densifled Densified silica fume that has been mechanically or chemically agglomerated and may have a bulk density typically greater than 500 kg/rn
(iii) Slurried Silica fume mixed with water to produce a slurry with or without the use of conditioners or other admixtures such as high-range water reducers or retarders. Typically slurries will contain 40 to 60% silica fume by weight but they are not necessarily’ limited to this range.
(b) Naturally occurring ciiiiorphous silica
(i) Powders Free flowing fine material.
(ii) Slurried Naturally occurring amorphous silica mixed with water to produce a slurry with or without the use of conditioners or other admixtures such as high- range water reducers or retarders. Typically slurries will contain 50 to 70% amorphous silica by weight but they are not necessarily limited to this range.
(iii) Pre-wened compressed filter cake Moist naturally occurring amorphous sil lea, with or without conditioners or admixtures. in cake form. Typically filter cakes will contain 65 to 85% amorphous silica by’ weight but they are not necessarily’ limited to this range.
NOTE: The performance of the different physical forms of amorphous silica will depend on the degree to which any formed agglomerations are dispersed.
AS NZS 3582.3 pdf download.