This document summarizes a project that aims to partially replace bitumen with low density polyethylene (LDPE) plastic waste in bituminous concrete. The goals are to address the solid waste management issue of plastic waste and improve the performance of bituminous roads. The project involved replacing bitumen at 2%, 4%, and 6% by weight with LDPE plastic waste and testing the modified bituminous concrete mixtures. Test results found that the plastic-modified mixtures had higher stability, stiffness, and strength compared to conventional mixtures. The document concludes that using plastic waste in bituminous concrete is an effective way to dispose of plastic waste while improving road performance.

1. PARTIAL REPLACEMENT OF BITUMEN
IN BITUMINOUS CONCRETE
BY
LOW DENSITY POLYETHYLENE [LDPE]
PROJECT TITLE

2. WHY THIS PROJECT?
 PLASTIC BEING A VERSATILE MATERIAL AND A
FRIEND TO COMMON MAN IN USEFUL WAY
BECOME A PROBLEM TO THE AMBIENT
ENVIRONMENT AFTER ITS USE.
 TODAY IN INDIA ONLY, NEARLY FOUR MILLION
TONNES OF PLASTIC IS USED AND HOPED TO
REACH 15 MILLION TONNES BY 2020.
 WASTE PLASTIC IS THE BIGGEST ISSUE IN SOLID
WASTE MANAGEMENT.
 BEING NON-BIODEGARDABLE, IT HAS A LONG
LIFETIME AND ITS BURNING GENERATES
HAZARDOUS AIR POLLUTANTS.

3. WHY THIS
PROJECT?
AS A CIVIL ENGINEERS, WE
HAVE COME WITH AN IDEA
TO UTILISE THIS WASTE
PLASTIC IN BITUMEN TO
PREPARE BITUMINOUS
CONCRETE THAT WILL
SOLVE TWO PROBLEMS:
1) SOLID WASTE
MANAGEMENT ISSUE.
2) BITUMINOUS ROAD
PROBLEMS

4. ABOUT THE PROJECT
 WE HAVE TRIED TO REPLACE BITUMEN IN
BITUMINOUS CONCRETE, THAT IS
USUALLY USED NOWADAYS FOR
ASPHALTING OF ROADS BY LOW DENSITY
POLYETHYLENE [LDPE].
 WE HAVE REPLACED BITUMEN IN
BITUMINOUS CONCRETE BY 2%, 4% AND
6% BY WEIGHT.

5. FEASIBILITY OF PROJECT
 LOW DENSITY POLYETHYLENE (LDPE)
CAN BE USED FOR REPLACEMENT DUE
TO REASON BELOW:
1) THERMOPLASTIC.
2) SOFTEN AT AROUND 130OC.
3) NO GAS EVOLUTION IN
TEMPERATURE RANGE (160-180)OC.
4) ACT AS A BINDER.

6. WHY LDPE ONLY NOT
OTHER PLASTIC?
 LDPE PLASTIC IS USED IN CARRY
BAGS, SACKS, MILK POUUCHES, BIN
LINING, COSMETIC AND DETERGENT
BOTTLES.
 IT IS USED IN ALL DAY TO DAY USED
PRODUCTS AND CONTRIBUTE TO 65%
OF TOTAL WASTE PLASTIC IN INDIA
ONLY.

7. PROCESS USED
 BASICALLY THERE ARE TWO
PROCESSES FOR MANUFACTURING
BITUMINOUS MIX AS PER IRC SP:98-
2013- WET AND DRY PROCESS.
 WE HAVE GONE FOR WET PROCESS AS
WE REPLACED BITUMEN BY LDPE.

8. WET MIX PROCESS

9. GUIDELINES OF IRC SP:98-
2013
 THE MATERIAL SHALL CONSIST OF ONLY
LOW DENSITY POLYETHYLENE (LDPE) OR
HIGH DENSITY POLYETHYLENE (HDPE).
 BLACK COLOURED PLASTIC WASTE IS A
RESULT OF REPEATED RECYCLING AND
SHOULD NOT BE USED.
 POLYVINYL CHORIDE (PVC) NOT TO BE
USED AS IT RELEASES LETHAL LEVELS OF
DIOXINES.

10. IMPORTANT GUIDELINE
 THERMO GRAVIMETRIC ANALYSIS (TGA)
OF THERMOPLASTICS HAS REVEALED GAS
EVOLUTION AND THERMAL
DEGRADATION MAY OCCUR BEYOND
180OC. THUS MISUSE OR WRONG
IMPLEMENTATION OF THIS TECHNOLOGY
MAY RESULT IN RELEASE OF HARMFUL
GASES, PREMATURE DEGRADATION, IF
TEMPERATURES ARE NOT MAINTAINED
DURING CONSTRUCTION.

11. WHAT’S SPECIAL IN THIS
PROJECT
 AS THERE IS IRC SP:98-2013 FOR PLASTIC
MODIFIED BITUMINOUS ROADS SO WHY WE ARE
WASTING TIME IN THIS PROJECT.
 BECAUSE THE FORMER IRC CODE ONLY PROVIDE
US GUIDELINES FOR BITUMINOUS MIX
PREPARATION BY DRY METHOD NOT BY WET
METHOD. RESEARCH AND DEVELOPMENT ARE
GOING ON IN THIS FIELD OF WET MIX
PREPARATION.

12. MATERIAL’S USED
 BITUMEN PROPERTIES AS CALCULATED
FROM TESTS BEFORE REPLACEMENT:
TESTS
CONDUCTED
IS CODE VALUE
PENETRATION
TEST
IS:1203 PENETRATION
VALUE: 69
DUCTILITY TEST IS:1208 DUCTILITY VALUE:
76.5 cm
SOFTENING TEST IS:1205 SOFTENING VALUE:
48.5 OC

14. MATERIAL’S USED
 AGGREGATES PROPERTIES AS CALCULATED
FROM TESTS BEFORE REPLACEMENT:
TESTS
CONDUCTED
IS CODE VALUE
AGGREGATES
CRUSHING
VALUE
IS:2386 (PART IV) 14.32%
AGGREGATES
IMPACT VALUE
IS:2386 (PART IV) 13.02%
AGGREGATES
ABRASION VALUE
(LOS ANGELES)
IS:2386 (PART IV) 18.52%

16. MATERIAL’S USED
 FILLER MATERIAL USED IS HYDRATED
CEMENT CONFORMING TO IRC:111-2009.

17. MATERIAL’S USED
 WASTE PLASTIC
1) PASSING 2.36mm IS SIEVE AND
RETAINING ON 0.6mm IS SIEVE.
2) DUST AND OTHER IMPURITIES NOT
MORE THAN 1%.

19. RESULTS AFTER REPLACEMENT
 ALL TEST RESULTS WERE GOOD AND
ONLY SHOWS WASTE PLASTIC
REPLACEMENT ONLY MODIFIES
BITUMINOUS CONCRETE MIX.

20. PENETRATION TEST RESULT’S
PERCENTAGE
OF LDPE
PLASTIC
ADDED BY
WEIGHT
0 2% 4% 6%
PENETRATION
VALUE AT 25 OC
69 66.67 64.33 62

21. DUCTILITY TEST RESULT’S
PERCENTAGE
OF LDPE
PLASTIC
ADDED BY
WEIGHT
0 2% 4% 6%
DUCTILITY
VALUE AT 27 OC
(in cm)
76.5 60.33 45 31

22. SOFTENING TEST RESULT’S
PERCENTAGE
OF LDPE
PLASTIC
ADDED BY
WEIGHT
0 2% 4% 6%
SOFTENING
VALUE (in OC)
48.5 52.25 56.5 62.5

23. MARSHALL TEST RESULT’S
 IT IS CONDUCTED IN TWO STAGE’S
 SPECIMEN PREPARATION.
 SPECIMEN TESTING.

24. SAMPLE
GRADED AND
DRIED
HEATING UP
SAMPLE MIX
WITH BITUMEN
MOULDING SAMPLE
READY FOR
TESTING

25. SPECIMEN PREPARATION
 WE USED FULLER’S FORMULA FOR GRADING
AND PREPARED SPREADSHEET FOR THAT
ALSO.
 WHERE ‘p’ is PERCENTAGE
PASSING THROUGH SIEVE
UNDER CONSIDERATION
‘D’ is LARGEST PARTICLE SIZE
‘d’ is SIEVE UNDER CONSIDERATION
‘n’ is FULLER INDEX AND TAKEN as 0.45 by
us.

26. SPECIMEN PHASE DIAGRAM

27. NOTATIONS
W1, W2, W3 AND Wb ARE
WEIGHT OF COARSE
AGGREGATES, FINE
AGGREGATES, FILLER AND
BITUMEN RESPECTIVELY.
V1, V2, V3, Vb AND Vv ARE
VOLUME OF COARSE
AGGREGATES, FINE
AGGREGATES, FILLER,
BITUMEN AND AIR VOIDS
G1, G2, G3 AND Gb ARE
SPECIFIC GRAVITIES OF
COARSE AGGREGATES,
FINE AGGREGATES,
FILLER AND BITUMEN

28. FORMULA’S
USED
Gt THEORETICAL
SPECIFIC GRAVITY
Gm BULK SPECIFIC
GRAVITY
Vv AIR VOIDS IN SAMPLE
Vb VOIDS FILLED WITH
BITUMEN
VMA VOIDS IN MINERAL
AGGREGATES
VFB VOIDS FILLED BY
BITUMEN

29. SPECIMEN TESTING
ANIMATED REAL

30. TESTING DATA FOR OPTIMUM
BITUMEN CONTENT
Sample
No.
Bitumen
Content
(%)
Marshall
Stability
Value
(kg)
Flow
Value (in
0.25mm
units)
Bulk
Specific
Gravity
Air Voids
(%)
VFB (%)
1) 4 1037.31 10 2.37 3.83 71.54
2) 4.5 1632.62 11 2.39 2.26 83.74
3) 5 2035.48 12 2.40 1.85 86.29
4) 5.5 2084.40 14 2.39 1.53 89.26
5) 6 1379.62 17 2.38 0.93 93.90

31. CHARTS
 MARSHALL STABILITY VS BITUMEN CONTENT

32. CHARTS
 FLOW VALUE VS BITUMEN CONTENT

33. CHARTS
 AIR VOIDS VS BITUMEN CONTENT

34. CHARTS
 BULK SPECIFIC GRAVITY VS BITUMEN CONTENT

35. CHARTS
 VFB VS BITUMEN CONTENT

36. OPTIMUM BITUMEN CONTENT
 BITUMEN CONTENT CORRESPONDING TO
MAXIMUM MARSHALL STABILITY VALUE= 5.5%
 BITUMEN CONTENT CORRESPONDING TO
MAXIMUM BULK SPECIFIC GRAVITY= 5%
 BITUMEN CONTENT CORRESPONDING TO MEDIAN
OF AIR VOIDS %= 5%
 AVERAGE VALUE= 5.2%
 THEREFORE OPTIMUM BITUMEN CONTENT= 5.2%

37. PLASTIC REPLACED SAMPLE’S
 AFTER FINDING THE OPTIMUM CONTENT
WEW PREPARED THE SAMPLE WITH 2%,
4% AND 6% PLASTIC REPLACEMENT AND
USED FULLER’S METHOD FOR GRADING
AND TESTED THE SAMPLE.

38. REPLACED SAMPLE MARSHALL TEST
DATA
Sample
Code
LDPE
Replaced
Bitumen
Content
(% by
weight)
Marshall
Stability
Value
(kg)
Flow
Value (in
0.25mm
units)
Bulk
Specific
Gravity
Air Voids
(%)
VFB (%)
A 2 2406.53 12 6.69 2.27 62.79
B 4 2534.55 18 5.54 2.30 68.38
C 6 2593.30 22 4.86 2.32 71.32

39. RESULT’S
 HIGHER SOFTENING POINT SO CAN WITHSTAND
HIGHER TEMPERATURE.
 LOWER PENETRATION VALUE SO INDIRECTLY
SHOWS INCREASE IN STIFFNESS.
 HIGHER MARSHALL STABILITY VALUE SHOWS
INCREASED LOAD CARRYING CAPACITY OF
PAVEMENT AS WELL AS INCREASE IN STRENGTH.
 NO GAS EVOLUTION AS TEMPERATURE WAS KEPT
AT 140 OC.
 DECREASE IN DUCTILITY VALUE SHOWS
INCREASE IN STIFFNESS.

40. OTHER POINT’S
 SOLID WASTE MANAGEMENT CAN BE
DONE IN THIS WAY.
 COST DECREASES AS BITUMEN GETS
DISPLACED BY WASTE PLASTIC.
 TEN LAKHS OR ONE TONNE CARRY BAGS
OF LDPE ARE ESTIMATED TO GET UED IN
ONE KILOMETRE.

41. ECONOMY OF THE PROCESS
 IN ORDER TO CONSTRUCT BITUMINOUS
CONCRETE ROAD OF 25mm THICK, 1 km LONG AND
3.5m WIDE, WE NEED BITUMEN OF NEARLY 12000
kg, SO IF WE REPLACE BITUMEN BY 6% WEIGHT
WE NEED 720 kg OF LDPE WASTE PLASTIC.

42. CONCLUSION
THE GENERATION OF WASTE PLASTICS IS
INCREASING DAY BY DAY. THE MAJOR POLYMERS
NAMELY POLYETHYLENE, POLYPROPYLENE,
POLYSTYRENE SHOW ADHESION PROPERTY IN
THEIR MOLTEN STATE. PLASTIC MODIFIED
BITUMEN FORMS BETTER MATERIALS FOR
FLEXIBLE PAVEMENT CONSTRUCTION AS THE
MIXES SHOWS HIGHER MARSHALL STABILITY
VALUE AND SUITABLE MARSHALL COEFFICIENT.
HENCE THE USE OF WASTE PLASTICS FOR
FLEXIBLE PAVEMENT IS ONE OF THE BEST
METHODS OF EASY DISPOSAL OF WASTE PLASTICS.

44. CONCLUSION
 IF ALL THE ROADS IN INDIA (3.3 MILLION KM)
ARE CONVERTED INTO PLASTIC TAR ROAD, ALL
THE WASTE PLASTIC AVAILABLE WILL BE USED
ON THE ROAD AND THE DISPOSAL OF WASTE
PLASTICS WILL NO LONGER BE A PROBLEM.

45. “Engineering problems are under-defined, there are many solutions, good, bad and
indifferent. The art is to arrive at a good solution. This is a creative activity,
involving imagination, intuition and deliberate choice.”
OVE ARUP
Engineers … are not superhuman. They make mistakes in their assumptions, in their
calculations, in their conclusions. That they make mistakes is forgivable; that they
catch them is imperative. Thus it is the essence of modern engineering not only to be
able to check one’s own work but also to have one’s work checked and to be able to
check the work of others.

46. THANK
YOU