DEPARTMENT OF CIVIL ENGINEERING

PANIMALAR ENGINEERING COLLEGE

(A CHRISTIAN MINORITY INSTITUTION

JAISAKTHI EDUCATIONAL TRUST

ACCREDITED BY NATIONAL BOARD OF ACCREDITATION

(AN ISO 9001:2000 CERTIFIED INSTITUTION)

BANGALORE TRUNK ROAD, VARADHARAJAPURAM,

NASARATHPET, POONAMALLEE,

CHENNAI- 600123.

EXPERIMENTAL STUDY ON INFLUENCE OF WASTE TYRES IN

BITUMINOUS CONCRETE

PRADEEP KANDASAMY NATARAJAN

pradeep.93kn@gmail.com

Mobile no: 2267003868

OBJECTIVE:

• Evaluate the feasibility of using waste tyres as

replacement material in bituminous concrete.

• Provide preliminary recommendations for the

use of waste tyres in the flexible pavements.

• To compare the results of the conventional mix

with the mix replaced with waste tyres.

• To suggest the mix proportion with replaced

tyres, giving the desired strength.

ABSTRACT:

The waste tires are replaced in the bituminous

concrete as a partial replacement for bitumen

and the stone aggregates.

Rubber powder is mixed with the bitumen as a

binder material and aggregates are replaced

with crumb rubber

Marshall Stability test is conducted to evaluate

the strength of the mix.

INTRODUCTION:

• In India the number of vehicles hitting the road

is increasing every day. With more than 33

million vehicles added to the Indian roads from

2007 to 2010, about 80 million tyres have hit

the roads

• Worldwide more than 981 million tyres are

thrown away each year and even less than 7%

are recycled, 11% are burned for fuel, and

5% are exported. The remaining 77% are

sent to landfills, stockpiled, or illegally

dumped.

• 765 million old tyres a year wasted across the

world.

Hence an effective method of disposing the waste tire is

studied in detail.

Materials:

• Stone Aggregate:

19mm, 13.2mm, 6.7mm, 2.36mm (dust)

• Bitumen

Aggregates:

The aggregates are specified based on their grain size,

texture and its gradation. Aggregate size is ascertained

by sieving through square sieves of successively

decreasing sizes. The required aggregate sizes are

chosen to fulfill the desired gradation.

AGGREGATE TEST:

Test Result IRC

Limitation

Crushing

strength test 22.42% <30%

Abrasion test 14.8% <30%

Impact test 23.54% <30%

SPECIFIC GRAVITY TEST:

Size of

aggregate

Weight

of

bottle

Weight

of bottle

+

aggregate

Weight

of bottle

+

aggregate

+ water

Weight

of

bottle

+

water

Specific

gravity

19 626 1045 1786 1524 2.669

13.2 626 1028 1773 1524 2.627

6.7 626 1005 1758 1524 2.614

2.36 626 995 1754 1524 2.636

Bitumen:

Bitumen is waterproof, durable, resistant to

strong acids, and possesses good cementing properties.

At normal temperature, bitumen is semi-solid, that is, it

takes time to flow. At higher temperatures, bitumen

behaves like a viscous liquid, whereas at a very low

temperature bitumen is as brittle glass. Bitumen is

believed to behave ‘viscoelastically’ at the standard

operating temperature of highways. Theoretically, it is

difficult to model the exact behavior of bitumen.

BITUMEN TEST RESULT:

S.NO BITUMEN TEST TEST RESULT

OBTAINED

1 Penetration @ 25 C 66

2 Softening point @ 5

C 54

3 Ductility @ 27 C cm

Min 75

4 Viscosity @ 135 C

cst Min 341

5 Specific gravity @

27 C 1.081

Marshall Stability Test:

Gradation:

Determination of quantity of materials required for

the mix:

Wt of aggregate (19mm) = 12 x (1200/100) = 144gm

Wt of aggregate(13.2mm) =18 x (1200/100) = 216gm

Wt of aggregate (6.7mm)= 20x (1200/100) = 240gm

Wt of aggregate (2.36mm) =50 x (1200/100) = 600gm

Total = 1200gm

OPTIMUM BITUMEN CONTENT:

%BITUMEN BY WEIGHT OF AGGREGATE VS

FLOW VALUE

2

3

4

4.5 5.0 5.5 6.0

flow

in

mm

%Bitumen by wt of aggregate

s.no Percentage

bitumen

Marshall

stability

(KN)

Flow

value

(mm)

Bulk

density

(gm/cc)

Percentage

air voids

1 4.5 13.91 2.35 2.389 3.61

2 5 14.99 2.90 2.412 2.10

3 5.5 16.62 3.37 2.430 0.77

4 6 10.25 3.50 2.421 0.55

%BITUMEN BY WEIGHT OF AGGREGATE VS

UNIT WEIGHT

%BITUMEN BY WEIGHT OF AGGREGATE VS

STABILITY

DESCRIPTION OF REPLACEMENT

MATERIALS:

Rubber powder:

The waste rubber tires are finely grinded to obtain the

rubber powder.

The Powder passing through the 250 micron sieve is

used for the replacement.

Mixing:

Bitumen is heated to a temperature of 160°C and then

the rubber powder is added to the bitumen.

Mix proportions:

Rubber powder is replaced in 5, 10, 15 and 20 %

by weight of the bitumen.

Test Results:

%RUBBER POWDER BY WEIGHT OF

AGGREGATE VS STABILITY

%RUBBER POWDER BY WEIGHT OF

AGGREGATE VS UNIT WEIGHT

2310

2360

2410

2460

4.5 5.0 5.5 6.0

un

it w

t in

kg

/m3

%Bitumen by wt of aggregate

12

13

14

15

16

17

18

19

4.5 5.0 5.5 6.0

Sta

bil

ity in

KN

% Bitumen by wt of aggregate

12.00

13.00

14.00

15.00

16.00

17.00

18.00

19.00

0.00 5.00 10.00 15.00 20.00 25.00 30.00

Sta

bil

ity in

KN

%Rubber powder by wt of Bitumen

2330

2335

2340

2345

2350

2355

2360

2365

2370

0.00 5.00 10.00 15.00 20.00 25.00 30.00

un

it w

t in

kg

/m3

%Rubber powder by wt of Bitumen

%RUBBER POWDER BY WEIGHT OF

AGGREGATE VS FLOW VALUE

Advantages:

The advantages of replacing bitumen with the

rubber powder are

• The stability of the powder replaced

bituminous mix is greater than the conventional

mix.

• An effective way of disposing the waste tires

without polluting the environment is obtained.

• The cost of the bituminous concrete decreases

by replacing bitumen with the rubber powder.

CRUMB RUBBER:

• The waste tyres are shredded to different sizes

using a shredder.

• The shredded pieces passing through the 19mm

and 13.2mm sieves are used as a replacement

for stone aggregates.

Replacement:

The crumb rubber replacement is done after the

gradation of the stone aggregates.

Crumb rubber is replaced in 5, 10% by weight

of the aggregates.

CRUMB RUBBER REPLACEMENT TEST RESULT

%CRUMB RUBBER BY WEIGHT OF

AGGREGATE VS STABILITY

%CRUMB RUBBER BY WEIGHT OF

AGGREGATE VS UNIT WEIGHT

%CRUMB RUBBER BY WEIGHT OF

AGGREGATE VS FLOW VALUE

3.0

3.2

3.4

3.6

3.8

4.0

0.0 5.0 10.0 15.0 20.0 25.0 30.0

flo

w in

mm

% Rubber powder by wt of Bitumen

5

6

7

8

9

10

11

12

0 5 10 15 20

Sta

bil

ity

in

KN

% by wt of aggregate

2080

2090

2100

2110

2120

2130

2140

2150

0 5 10 15 20

un

it w

t in

kg/m

3

% by wt of aggregate

3.0

3.5

4.0

4.5

5.0

5.5

6.0

0 5 10 15 20

flow

in

mm

% by wt of aggregate

Advantages:

• An effective method of disposal of waste tires.

• The replacement makes the construction of

bituminous concrete cost effective.

Disadvantages:

• The stability of the mix decreases when

replacement is more than 5% by weight of

aggregates.

CONCLUSION

The following conclusions can be drawn from the

above investigations:

From the study it is found that by replacing

bitumen with 15% of weight by rubber powder

the desired result is obtained.

The overall stability increases by 14%

compared to conventional bituminous concrete.

The replacement of stone aggregates by the

crumb rubber however did not give the desired

output.

The stability may be increased when the crumb

rubber used is of size less than 13.2mm.

Thus by replacing the bitumen with rubber

powder we can save the accumulation of rubber

tyres to a greater extent.

FUTURE STUDY:

Research work has to be carried on effectively

using the crumb rubber as a replacement

material for stone aggregates.

The problem for the reduction in the stability of

the crumb rubber replaced mix is found to be

the larger size of the aggregates.

Hence research has to be carried on using the

crumb rubber of smaller size and with irregular

shapes.

Reference:

Meles, D., & Bayat, A. (2012) “Compression

Behavior of Large Size Tire Derived Aggregate

for Embankment Application.” Accepted.

ASCE Journal of Materials in Civil

Engineering.

Nuha S. Mashaan, Asim Hassan Ali,

Mohamed RehanKarim and MahrezAbdelaziz.

“Effect of blending time and crumb rubber

content on compacting-properties of crumb

rubber modified asphalt binder” international

journal of the physical sciences doi: vol. 6(9),

pp. 2189-2193, 4 may, 2011.

Prof Prithvi Singh Khandal “Quality control

requirements for using crumb rubber modified

bitumen (crmb) in bituminous mixtures”.

Indian roads congress, indian highways, 31aug

2006.

IRC: SP: 53, ‘Tentative Guidelines on use of

polymer and Rubber modified Bitumen in Road

construction’, Indian Road congress (IRC),

2002.

F.A.Aisen, F.K.Hymore and R.O.Ebewele.

“Application of ground tyre rubbers in asphalt

concrete pavements” Indian journal of

engineering and materials sciences doi: vol 13,

august 2006, pg 333-338.