Pure Natural Minerals
Chemicals & Oxides
Fly Ash
|
S. No.
Component /Characteristics
Unit
British Standard BS:3892
American Standard ASTM :C618
Indian Standard: 3812 (Part 1) : 2003 Fly Ash^
SPFA
CPFA
Indian Standard: 3812 (Par 2): 2003 Fly Ash^
SPFA
CPFA
|
Chemical Requirements |
|
1.
SiO2 + Al2O3 + Fe2O3
%
--
70
70
50
70
50
2.
Sio2 Min
%
--
--
35
25
35
25
3.
Reactive SiO2 Min (Optional)
%
--
--
20
20
--
--
4.
CaO, Max
%
--
--
--
--
--
--
5.
MgO, Max
%
4
--
5
5
5
5
6.
Total S as SO3, Max
%
25
5
3
5
5
5
7.
Alkali as Na2O, Max
%
--
1.5
1.5
1.5
1.5
1.5
8.
Total CI, Max
%
--
--
0.05
0.05
0.05
0.05
9.
Loss on Ignition, Max
%
7
12
5
5
5
5
10.
Moisture content, Max
%
1.5
3
2
--
--
--
|
Physical Requirements |
|
1.
Specific surface (Blaine), Min
M2/kg
Variable
325
320#
200
2.
Sieve residue on 45 um sieve, Max
%
--
32
34(optional)
50(optional)
3.
Control figure (Product of loss and sieve residue on 45 µm sieve), Max
%
--
255
--
--
4.
Lime reactivity** (Average compressive strength), Min
N/mm2
--
--
4.5
--
5.
Compressive strength at 28 days, Min
N/mm2
--
--
Not less than 80% of the strength of corresponding plain cement mortar cubes
--
6.
Drying shrinkage, Max
%
--
--
--
--
7.
Soundness (Autoclave), Max
%
--
--
0.8
0.8
|
^Part I : For use as pozzolana in cement, cement mortar and concrete
^Part II : For use as admixture in cement, cement mortar and concrete
SPFA : Silicious Pulverised Fuel Ash
CPFA : Calcareous Pulverised Fuel Ash
#Fly Ash of fineness 250 M2/kg (Min) is also permitted to be used in the manufacture of Portland pozzolana cement by intergrinding it with Portland cement clinker if the fly ash when ground to fineness of 320 m2/kg or to the fineness of the resultant Portland pozzolana cement whichever is lower, meets all the chemical and physical requirements.
** The method of test covers the procedure for determining the reactivity of the pozzolanic material with hydrated lime, as represented by compressive strength of standard mortar