1. Zeeshan Ahmad*, Vartika Varshney, J.P. Tegar
Evaluation Of Mechanical Properties Of Alkali Activated Slag Concrete Blended With Polystyrene Fibers & Accelerator
Zeeshan Ahmad*, Vartika Varshney, J.P. Tegar
National Institute Of Technical Teacher’s Training And Research, Bhopal, INDIA
Introduction
Sodium Silicate as Alkali Activator.
Accelerator and Superplasticizer.
Polystyrene Shredding- It’s the shredding of waste disposable cups.
Ground Granuled Blast Furnace Slag.
Sample
Slag
(%)
Shredding (%)
Admixture
7-Days
(N/mm2)
28- days CC
2.4
4.41
6.23 S1 5
0.45
3.62
5.65 S2 10
3.65
5.59 S3 15
3.59
5.01 S4 20
2.64
4.97 S5 25
2.71
4.53 S6 27
2.78
4.18 S7 30
2.63
3.33
Global warming is one of the most serious concern of the world today. The production of Ordinary Portland Cement (OPC) includes greenhouse gases emission, high energy consumption and natural resource depletion. The substitution of OPC is done by using alkali activated cement like Ground Granuled Blast Furnace Slag. Polystyrene fibers are made from shredding waste disposable cups. It imparts ductility to concrete and avoids brittle failure and slows down the crack propagation in concrete. It also reduces the issue of solid waste and high costs incurring in recycling.
Compressive Strength Of Nominal Concrete With Fibres
Blast Furnace Slag
Weighted Materials
Sample
Slag (%)
Shredding (%)
Admixture (%)
7-days
(N/mm2)
14-days
28- days CC
2.4
23.88
27.32
35.52
MD1 5
0.40
23.58
27.05
34.24
MD2 10
23.01
26.86
34.12
MD3 15
22.37
26.52
32.73
MD4 20
22.01
26.05
32.67
MD5 25
21.87
25.15
32.50
Opt 27
21.72
23.21
32.47
MD6 30
20.93
24.89
32.22
MD7 35
20.02
24.10
29.09
Waste Cup’s Shredding
Dry Mix
Objectives
Results
Replacement of cement by industrial by product.
Achieving higher target mean strength as comparative to conventional cement concrete mix.
Increment in tensile strength
Enhancement in the flexure properties of concrete.
Reduction in cost of concrete as comparative to cost of conventional mixes.
Compressive Strength:
Compressive strength test of concrete is conducted on the sample cubes of size 15 cmX15 cmX15 cm as per IS:
Conclusions
Cement can be replaced up to 27% by weight.
Target mean strength of M27 mix is achieved in the cost of M20.
Split Tensile Strength is increased by 53%.
Crack propagation is slow as comparative to conventional mixes.
Increase in ductility during failure due to the presence of polystyrene shredding.
Cost is reduced by 31% as compared to conventional mixes.
It is observed that Alkali Activated Slag gains strength at a slow rate at initial stage, accelerator is used to increase the rate of gaining strength at earlier stage.
Test Specimen Cubes
Compressive Strength Alkali Activated Slag Concrete
Split Tensile Strength:
Split Tensile test is conducted on the cylinder of dimensions 15 cm diameter and 30 cm length as per IS:
Materials
Ordinary Portland Cement conforming to IS
Coarse and fine aggregates
Brittle Failure
Ductile Failure