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Silica fume is ultrafine particles collected from exhaust gas generated during pro’duction of metallic silicon or ferrosilicon in electric arc furnaces. The use of silica fumefor an admixture for concrete has long been obscure in Japan because the silica fumeproduction is limited due to high cost of electricity. อย่างไรก็ตาม, as the remarkable effectof silica fume in enhancing the strength, durability and workability of concrete hasbeen widely recognized. the use of imported silica fume has become increasingly common. This Standard was first established in 2000 for responding to the demand for aquality standard for silica fume. Since the last revision which was made in 2011. theapplications of silica fume have diversified and the relevant technology advanced. Thisrevision’s aim is to revise some of the quality requirements and test procedures in or’der to accommodate and reflect these changes.
No corresponding International Standard has been established at this point. Thecomparison table between previous and current editions of this Standard on technically
significant revisions is given in Annex G
1. Scope
This Standard specifies the silica fume to be used as an admixture for concrete ormortar (hereafter referred to as silica fume).
NOTE : Silica fume is available in powdery, granular and slurry forms.
2. Normative references
The following standards contain provisions which, through reference in this text,constitute provisions of this Standard. The most recent editions of the standards (in’cluding amendments) indicated below shall be applied.
- JIS A 1108Method of test for compressive strength ofconcreteJIS A 1116Method of test for unit mass and air content of fresh concrete by massmethod
- JIS A 1128Method of test for air content of fresh concrete by pressure methodJIS A 1132Method of making and euring concrete specimens
- JIS A 1171Test methods for polymer.modified mortar
- JIS A 5308 Ready-mixed concrete
- JIS A 6204Chemical admixtures for concrete
- JIS H 6201 Platinum crucibles for chemical analvsis
- JIS K 0050 General rules for chemical analysis
