This presentation contains key areas I worked during my graduate training at JSW Steel Limited.

1. Graduate Training at JSW
Kalaivanan Murthy
Graduate Engineer Trainee
Civil & Eng. Services Department
JSW Steel Limited

2. Slag
“A non-metallic product consisting essentially of silicates and alumino
silicates of calcium and other bases that is developed in molten condition
simultaneously with iron in blast furnace” – ASTM C125
2
INTRODUCTION
Q u i c k F a c t s
•3.3b tons: India’s sand requirement
•0.3m tons: Annual req. of sand at JSW
•Rs.1200/ton: Cost of sand in Bangalore
•100% slag: Sydney Airport Extn (2010)
•6mtpa: Gen slag at JSW in 2020 estd
•60k tons/year: Req. for cement plant
LD
33%
BF
67%
Major Chemical Constituents
Calcium (CaO) 36 %
Silica (SiO2) 33 %
Alumina (Al2O3) 19 %
Magnesia (MgO) 7 %
Major Applications
Roads & Pavements, Concrete Aggregates, Construction Fill, Shore
Protection, Grit Blasting, Sub-soil Drains, Stabilizing Binder, Fertilizers.

3. 3
Plastering
• Strength: Screened G-Slag (2mm) with PSC reached strength of 30 MPa, at
end of 28 days and at mix ratio of 1:4.
• Durability: G-Slag is free from reactive forms of silica and deleterious
compounds that makes it durable.
• Workability: Due to lack of fines particles (<600µm), workability is less
with G-Slag, that can be overcome by grinding.
0% 20% 40% 60% 80% 100%
1
2
3
4
Wt. Fraction (%)
TrialNo.
Mix Proportion
Cement
GBS(<300um)
GBS (300-
600um)
GBS (600-
1000um)
BEST MIX
9.9
14.3
30.1
3.2
4.6 7.1
0
5
10
15
20
25
30
35
0 5 10 15 20 25 30
Strength(MPa)
Time (days)
STD. MIX
ESN MIX

4. 4
Concrete
• G-Slag, when used as fine aggregate in concrete, achieves target mean
strength upto M25 grade. Beyond that it fails by a marginal amount.
• Though it conforms to Zone-I gradation, it fails to achieve higher strengths
that sand could attain, in case of M30 or above.
• As the water absorption for slag is three times the sand, as such, the water
availability for cement hydration needs to be ensured.
Fig. Compressive Strength Test
0
5
10
15
20
25
30
35
40
0 10 20 30
CompressiveStrength(MPa)
Time (days)
Compressive Strength vsTime
M25 STRD.
M25 (100%)
M25 (75%)
M25 (50%)
M25 (25%)

5. 5
Merits & Demerits
+ The molten slag, generated at 1500 ˚C, is rapidly quenched frees
slag from any deleterious or organic compounds.
+ The specific gravity of G-Slag is 4/5th of sand, thus reducing the
overall weight of structure and savings in transportation.
+ The coefficient of expansion of slag (αs=0.000006/°F) is almost
equal to cement establishing a unison compatibility.
+ Due to absence of chloride ions in G-Slag, it can be used in marine
areas, and also reduces risk of corrosion in reinforcement.
˗ Inadequacy in fines (<300µm) results in bleeding, as a remedy,
supplementary binding material or air entrains can be used.
˗ The fineness modulus of G-Slag (3.3) is higher than preferred range
(2.3-3.1), thus a coarser fine aggregates, or inadequate fines content.
˗ Presence of glassy particle in G-Slag makes handling difficult, but is
a prime compound attributing to adhesiveness of GGBS.

6. 6
Bottlenecks
• Any material to be used in construction needs approval from Bureau of
Indian Standards, that limits the scope of applicability.
• Improper use of G-Slag due to lack of knowledge, may lead to disastrous
consequences detrimental to JSW brand, thus public awareness is essential.

7. Thank You
An exciting opportunity to hone professional skills with
personal fulfillment..
7