1. INFLUENCE OF GGBFS ON PROPERTIES OF CONCRETE PAVEMENTBy
Binod Kumar
Pr. Scientist , CRRI, New Delhi
&
Mrs. Lopamudra Sengupta
VP, JSW Cements Ltd., Mumbai
L. R. Manjunath
DGM, JSW Cements Ltd., Mumbai

2. PQC REQUIREMENTS Structural & Functional Performance
Concrete Flexural Strength: kg/cm2
(M35 - M40 Grade)
Slump: mm(paver), mm(manual)
Cement content: 425 kg/m3 max.
Use of superplasticisers
Use of Slag & Fly ash

3. CHEMICAL PROPERTIES OF GGBFS
USED IN PQC
Sr. No.
Constituent
Content, % by Mass
Requirements as per IS: 1
Silica (SiO2)
34.2 - 2
Alumina (Al2O3)
17.5 3
Calcium Oxide (CaO)
35.0 4
Iron Oxide (Fe2O3)
0.74 5
Magnesia (MgO)
10.1
Max 17% 6
Sulphide as Sulphur
0.42
Max 2.% 7
Manganese Oxide
0.12
Max 5.5% 8
(CaO + MgO + Al2O3) / SiO2
1.83
≥ 1.0 9
Glass Content 96
≥ 85 %

4. PHYSICAL PROPERTIES OF GGBFS
USED IN PQC
Sr. No.
Property
Test Value 1
Sp. Gravity
2.956 2
Blaine’s Fineness, m2/kg
375 3
Retained on 45 micron in Wet
Sieving, %
8.9 4
Lime reactivity, N/mm2
15.3

5. PQC MIX PROPORTIONS Mix Designat ion GGBFS Replacem ent Level, %
(kg/m3)
Slag
Sand
10 mm
20 mm
Water S0
400
166.00
S10 10
360 40
S20 20
320 80
S30 30
280
120
722.00
341.46
802.54
S40
240
160
S50 50
200
720.32
800.60
165.97
S60 60

6. PQC PROPERTIES Workability Compressive Strength Flexural Strength
Drying Shrinkage
Abrasion Resistance
Plastic Shrinkage Cracking

7. WORKABILITY

8. COMPRESSIVE STRENGTH

9. Flexural Strength, (N/mm2)
Mix Desig natio n
Flexural Strength, (N/mm2)
7 Days
28 Days
90 Days S0
3.5
5.4
5.8
S10
3.7
5.3
6.2
S20
4.3
5.7
6.6
S30
4.1
5.6
6.7
S40
3.9
5.5
6.9
S50
3.6
S60
3.0
4.0
4.9

10. FLEXURAL STRENGTH, PQC THICKNESS AND COST SAVING
Mix Designation
90 D Flexural Strength, (N/mm2)
PQC Thickness, mm
Cost Saving (2Lane/km)
Rs5/kg,
(Lakh Rs.)
Rs7000/CM, (Lakh Rs.) S0
5.8
250 -
S10
6.2
240
4.08
5.95
S20
6.6
230
7.82
11.9
S30
6.7
225
11.47
14.87
S40
6.9
220
14.96
17.85
S50
21.25
Nil
S60
4.9
At S40 Level 120 km road can be constructed in the cost of 100 km

11. DRYING SHRINKAGE

12. LOAD TRANSFER AT JOINT AND AGGREGATE INTERLOCKING
Doweled joints
Sawing of joints

13. Aggregate interlocking
Less Shrinkage
Closed Crack Under Saw Cut Helps Load Transfer
High Shrinkage
Open Crack Under Saw Cut
Reduced Load Transfer

14. ABRASION RESISTANCE (DEPTH OF WEAR)
Abrasion Machine
Tested Sample

15. DEPTH OF WEAR

16. PLASTIC SHRINKAGE CRACKING
High Temperature
High Wind Velocity
Low Air Humidity
Low Water Cement
Ratio, <0.38

17. CONVENTIONAL Vs LATEST PQC (M40) MIXES
QuantityKg/Cu. m
Cement,
Fly Ash / GGBFS
W/CM
Water SP
PS Cracking Tendency
Conventional
400
Nil
0.38
152
SNF
Low
PQC with Fly Ash
(Latest)
320 80
PCE
Very High
PQC with GGBFS
240
160
Very Low

18. CONCLUSIONS
Workability of concrete mixes do not change with the use of any amount of GGBFS. Use of suitable plasticiser can take care of the workability of the mix without changing the water requirement.
Both short term (7 & 28 days) and long term (90 days) compressive as well as flexural strength of concrete is increased when cement is partially replaced by GGBFS up to a level of 40%. When 50 % cement is replaced by GGBFS, the strength of the concrete remains almost same.

19. CONCLUSIONS
Abrasion resistance of M40 Grade PQC containing different amount of GGBFS was observed to be adequate enough for its use in concrete pavement construction.
Drying shrinkage of concrete reduces with the increase in GGBFS content. Thus, concrete containing GGBFS is comparatively more suitable than conventional concrete for road construction
Plastic Shrinkage Cracking Tendency is reduced with GGBFS
GGBFS can be used as partial replacement of OPC up to 50 % without compromising the requirement of short term and long term strength of PQC.

20. Thank You