This document summarizes an experimental investigation into the effects of partially replacing cement with fly ash in rubberized concrete. Concrete mixes were prepared with 0-20% fly ash replacing cement and 5% rubber replacing coarse aggregate. Testing found that workability initially decreased but then increased with higher fly ash content. Compressive strength initially decreased but then increased as fly ash content rose. The study aims to utilize waste materials like fly ash and rubber in concrete production to reduce environmental impacts.

1. PRESENTED BY:
SUNIL KUMAR (CIVIL3B)
PROJECT GUIDE:
Er. CHHAVI GUPTA
DEPARTMENT OF CIVIL ENGINEERING

2.  The results of an
experimental investigation
to study the effects of
partial replacement of
cement with flay ash in
rubberized concrete.
 Percentage of rubber used
in this study was 5%,
replaced with coarse
aggregate.
 Fly ash varies from 0-20%,
replaced with cement.
 Grade of concrete M20.

3.  Concrete is one of the main component in any concrete
masonry construction
 Concrete composes of cement ,fine aggregate, coarse
aggregate
 Researches have shown that these components can be
replaced to some extent by fly ash, rubber, plastic,
stone dust etc..,

4.  Growth of cement usage leads to the greater
production of CO gas which is one of the major cause
for GLOBAL WARMING
2

5. Excavation of sand and stones from river banks is one of
the main cause for disasters caused due to FLOODS

6. FLY ASH
 Fly ash is finely divided residue obtained from the
combustion of powdered coal
 CLASS F fly ash from thermal power plants collected
and is used for about 5%to 20%to replace cement.
 10% and 20% replacement of cement specimens have
been prepared.

7.  Rubber from scrap tyres is one of the most recent waste
materials investigated for its potential use in
construction industry.

9. CEMENT
 Ordinary Portland cement (53 grade) Ultratech cement
is used.
COARSE AGGREGATE
 Normal coarse aggregate of 20 mm size is used.

10. FINE AGGREGATE
 River sand which is available locally is used as fine
aggregate for entire process.

11. GRADE OF CONCRETE
 The mix is targeted for M20 grade(Nominal mix).
WATER-CEMENT RATIO
 Water-cement ratio is be taken as 0.45.

12. CONCRETE
MIX
PROPORTION
MIX IDENTITY NO. OF
SPECIMENS
Concrete mix with
100%NCA+100%ce
ment+0%rubber+
0%fly ash
CR0F0 6
95%NCA+90%cem
ent+5%rubber+10%
fly ash
CR5F10 6
95%NCA+80%cem
ent+5%rubber+20%
fly ash
CR5F20 6

13. MIX
IDENT
ITY
(kg)
NO.
OF
BLOC
KS
CEMENT
(kg)
SAND
(kg)
NORMAL
COARSE
AGGREGA
TE(NCA)
(kg)
RUBBER
CHIPS
(kg)
FLY
ASH
(kg)
WATER
(ml) (w/c
ratio
=0.45)
CR0F0 6 10 15 30 -- -- 4500
CR5F10 6 9 15 28.5 1.5(5%
replacem
ent of
NCA)
1(10%r
eplace
ment to
cement)
4500
CR5F20 6 8 15 28.5 1.5(5%
replacem
ent of
NCA)
2(20%
replace
ment to
cement)
4500

14.  FRESH CONCRETE TEST
Slump cone test
 HARDENED CONCRETE TEST
Compressive strength test

15. Slump Cone
Test

16. S.NO MIX IDENTITY SLUMP
VALUE(mm)
1 CR0F0 45
2 CR5F10 40
3 CR5F20 43.5
Slump cone test values

17. Slump chart
3.6 3.8 4 4.2 4.4 4.6
CR0F0
CR5F10
CR5F20
SLUMP
SLUMP

18. Compressive strength test

19. Compressive strength test results
MIX PROPORTION MIX
IDENTITY
AVERAGE COMPRESSIVE
STRENGTH
7 DAYS 28 DAYS
Concrete mix with 100% NCA
+ 100% Cement + 0% Rubber
chips + 0% FA
CR0F0 17.96 23.70
Concrete mix with 95% NCA
+ 90% Cement + 5% Rubber chips
+ 10% FA
CR5F10 15.23 19.04
Concrete mix with 95% NCA
+ 80% Cement + 5% Rubber chips
+ 20% FA
CR5F20 18.09 23.80

20. 7 days
28 days
0
5
10
15
20
25
CR0F0 CR5F10 CR5F20
Compressive strength variation
for 7 &28 days
(N/mm^2)

21.  The workability decreases when we replace coarse
aggregate with 5% rubber and cement by 10% fly
ash
 Again the workability increases as greater
percentage of fly ash increases the workability
 The strength of concrete decreases with increase in
percentage of fly ash first and again increases as
the percentage of fly ash increases.

22.  “Influence of fly ash on mechanical properties of
rubberized concrete” by M.Mishra,K.C.Panda.
 “Rubber tyre particles as coarse aggregate” by
N.N.Eldin ,A.B.Senouci ,journal of materials in
civil engineering,vol-5,pp.478-96.
 I.B.Topcu,(1995),”The properties of rubberized
concrete", cement concrete
research,vol.25(2),pp.304-310.
 A.Yilmaz&N.Degirmenci,(2009),”Possibility of
using waste tyre rubber and fly ash with Portland
cement concrete as construction materials", waste
managements,vol29(5),pp.1541-1546.