performance study on recycled plastics in concrete

PERFORMANCE STUDY ON RECYCLED PLASTICS IN CONCRETE

1. INTRODUCTION

1.1 Background of plastic

1.2 Need for study

1.3 Scope and Objectives

2. LITERATURE REVIEW

2.1 Recycled plastic

3. EXPERIMENTAL WORK PHASE

3.1 Introduction

3.2 Work plan

3.3 Scheme of the work

4. RESULTS AND DISCUSSION

4.1 Test results

4.1.1 Compressive strength

4.1.2Flexural strength

5. CONCLUSION

1

CHAPTER 1

INTRODUCTION

1.1 BACK GROUND OF PLASTIC

The changed life style and endlessly increasing population has resulted

in a significant rise in the quantity of plastic waste. The world’s annual

consumption of plastic materials has increased from around 5million tons in the

1950’s to nearly 100 million tons in recent times, resulting in a significant increase

in the amount of plastic waste generation. Out of this waste , a significant part is

recycled but the majority of post - consumer plastic wastes , like shampoo sachets,

carry – bags , nitro packs , milk and water pouches etc., though recyclable,

remains comparatively untouched as they are difficult to separate from household

garbage.

In most of the cases, such post – consumer waste either litters all

around or is disposed off by land filling. The disposal of post – consumer plastic

waste in this manner poses significant environmental hazards as it results in

reduction in soil fertility , reduction in water percolation , emission of toxic gases ,

health hazard to animals and birds consuming the wastes , poor drainage due to

land fill , pollution of ground water due to leaching of chemicals from these waste

products etc.Looking to the global issue of environmental pollution by post –

consumer plastic waste , research efforts have been focused on consuming this

waste on massive scale in efficient and environmental friendly manner .

Researchers planned to use plastic waste in form of concrete ingredient

as the concrete is second most sought material by human beings after water . The

use of post – consumer plastic waste in concrete will not only be its safe disposal

2

method but may also improve the concrete properties like tensile strength ,

chemical resistance , drying shrinkage and creep on short and long term basis.

1.2 NEED FOR STUDY

Nowadays one of the major problems in construction industries is

insufficient and unavailability of construction materials , on the other side the main

environmental problem is the disposal of the waste plastics.

In this experimental study , an attempt has been made to use the

plastics in concrete and studies have been conducted to focus on the behavior of

flexural and compression members under various proportions of plastics.

Types of plastics will be selected and mixed with concrete in various

proportions and the specimens are casted and tested for its compression and

flexural strength respectively.

1.3 SCOPE AND OBJECTIVES

The scope of this work is limited to the development of a suitable

mix design and to compare the compressibility and flexural aspect of Natural Poly

Propylene (NPP) mixed concrete and Polyethylene Terephthalate (PET) mixed

concrete against the plain cement concrete.

The main objective of this project is to enhance the best

environmental alternative for solving the problem of disposal.

The development of new construction materials using recycled

plastics is important to both the constructions and the plastic recycling industries.

3

CHAPTER 2

LITERATURE REVIEW

2.1 RECYCLED PLASTICS

Plastics are the organic polymer materials having carbon as the

common element in their make up. The polymers consist of combination of carbon

with oxygen , hydrogen , nitrogen and other organic substances. Plastic are

normally stable and not bio – degradable, so , their disposal poses problems.

Research works are going on in make use of plastic wastes

effectively as additives in bitumen mixes for the road pavements (Lakshmipathy

et., al, 2003) , (Vasudevan 2004) , repair and upgradation of reinforced concrete

silos using fiber reinforced plastics (FRP) , (Bhedasgaonkaret., al 2004).

A laboratory experimental study carried out to utilize waste

plastics(in the form of strips) obtained from milk pouches in the pavement

constructions (Chandrakaran 2004) , pilot level studies using industrial PVC scrap

to develop PVC board (Agarwal 2004).Re engineered plastics are used for solving

the solid waste management problems to great extent.

This study attempt is to give a contribution to the effective use of

domestic waste plastics in concrete in order to prevent the environmental strains

caused by them, also to limit the consumption of high amount of natural resources.

4

CHAPTER 3

EXPERIMENTAL WORK PHASE

3.1 INTRODUCTION In this chapter, a work plan is formulated, which outlines the entire

procedure carried out during the experimental investigation.

3.2 WORK PLAN The experimental investigation was carried out in different phases.

The various phases involved have been explained as follows.

The first phase involved the collection of materials Natural Poly

Propylene (NPP), Polyethylene Terephthalate (PET).

The second phase involved the calculation of a suitable design mix

for plain cement concrete so that it satisfies the requirements of a high strength

concrete, when coarse aggregate is replaced with suitable recycled plastics.

The third phase included the casting, curing and testing of the

plain cement concrete cubes and beams, recycled plastics cubes and beams.

A general overview of the phases involved is shown in figure 3.1

5

Fig 3.1 phases of the experimental work

6

Materials collection

(NPP, PET)

Mix Proportion

Casting

Plain Cement Concrete

NPP Mixed Concrete

PET Mixed Concrete

Study of Strength properties

1.Flexural Strength

2.Compression Strength

Analysis Of Results

Conclusion

CHAPTER 4

RESULTS AND DISCUSSION

4.1 TEST RESULTS

4.1.1 Compressive Strength

Most of the desirable characteristics properties of concrete

are qualitatively related to its compressive strength. Therefore it is necessary to

calculate the performance and strength of the concrete. The compressive strength is

calculated from the failure load divided by the cross sectional area resisting the

load and reported in units of Mpa.

4.1.1.1 COMPRESSIVE STRENGTH OF PLAIN CEMENT

CONCRETE (PCC) CUBE

NPP = 0%

PET= 0%

Table 4.1 Compressive strength of plain cement concrete cube

Specimen IdentityCompressive strength

14 days (N/mm²)

Compressive strength

28 days (N/mm²)

PCC 16.70 24.20

PCC 21.00 26.60

PCC 20.70 25.60

Average Value 19.46 25.46

7

4.1.1.2 COMPRESSIVE STRENGTH FOR 1% NPP

REPLACEMENT

NPP=1% PET=0%

Table 4.2 Compressive strength of NPP (1%) mixed concrete cube

Specimen Identity Compressive Strength 14 days (N/mm²)

Compressive Strength 28 days (N/mm²)

NPP 1% 21.40 31.50

NPP 1% 19.00 30.10

NPP 1% 20.00 32.50



REPLACEMENT

NPP= 3% PET= 0%



Compressive Strength 28 days(N/mm²)

NPP 3% 21.00 32.50

NPP 3% 20.05 29.20

NPP 3% 21.09 32.50


8


REPLACEMENT

NPP= 5% PET= 0%



Compressive Strength 28 days(N/mm²)

NPP 5% 10.59 20.28

NPP 5% 9.75 20.55

NPP 5% 10.07 20.64


Table 4.5 Compressive strength of NPP specimens

Specimen Identity Compressive Strength

14 days (N/mm²)

Compressive strength

28 days (N/mm²)PCC 19.46 25.46

NPP 1% 20.13 31.36

NPP 3% 20.71 31.40

NPP 5% 10.13 20.49

9

PCC NPP 1 % NPP 3% NPP 5%0

5

10

15

20

25

30

35

19.46 20.13 20.71

10.13

25.46

31.3631.40

20.49

28 DAYS14 DAYS

% Replacement of NPP

Com

pres

sive

stre

ngth

N/m

m²

Fig 4.1 Compressive strength of PCC & NPP

14 DAYS 28 DAYS0

5

10

15

20

25

30

35

19.46

25.46

20.13

31.36

20.71

31.4

10.13

20.49

PCCNPP 1%NPP 3%NPP 5%

Com

pres

sive

ctre

ngth

N/m

m²

Fig 4.2 Comparison between Compressive Strength of PCC & NPP

10

4.1.1.5 COMPRESSIVE STRENGTH FOR 1% PET

REPLACEMENT

PET= 1% NPP= 0%

Table 4.6 Compressive strength of PET (1%) mixed concrete cube



PET 1% 19.60 26.06

PET 1% 19.43 23.45

PET 1% 20.45 27.60



REPLACEMENT

PET= 3% NPP= 0%




PET 3% 21.06 32.20

PET 3% 20.05 30.50

PET 3% 20.08 29.40


11


REPLACEMENT

PET= 5% NPP= 0%




PET 5% 8.70 13.50

PET 5% 8.90 13.90

PET 5% 8.50 13.20


Table 4.9 Compressive strength of PET specimens

Specimen Identity Compressive Strength

14 days (N/mm²)

Compressive Strength

28 days (N/mm²)PCC 19.46 25.46

PET 1% 19.82 25.70

PET 3% 20.39 30.70

PET 5% 8.70 13.53

12

PCC PET 1% PET 3% PET 5%0

5

10

15

20

25

30

35

19.46 19.82 20.39

8.7

25.46 25.70

30.70

13.53 28 DAYS14 DAYS

% Replacement of PET

Com

pres

sive

stre

ngth

N/m

m²

Fig 4.3 Compressive strength of PCC & PET

14 DAYS 28 DAYS0

5

10

15

20

25

30

35

19.46

25.46

19.82

25.7

20.39

30.7

8.7

13.53PCCPET 1%PET3%PET 5%

Com

pres

sive

stre

ngth

N/m

m²

Fig 4.4 Comparison between Compressive Strength of PCC & PET

13

Table 4.10 Comparison between Compressive Strength of PCC, NPP & PET

for 14 days and 28 days

Compressive Strength of PCC for 14 days= 19.46 N/mm²

Compressive Strength of PCC for 28 days= 25.46 N/mm²

Specimen

Identity

% Replacement of Recycled Plastic1% 3% 5%

14 days 28 days 14 days 28 days 14 days 28 days

NPP 20.13 31.36 20.71 31.40 10.13 20.49

PET 19.82 25.70 20.39 30.70 8.70 13.53

0% 1% 3% 5%0

5

10

15

20

25

19.4620.13 20.71

10.13

19.82 20.39

8.70PETNPP

% Replacement of NPP & PET

Com

pres

sive

Stre

ngth

N/m

m²

Fig 4.5 Comparison between Compressive Strength of NPP & PET for 14 days

14

0% 1% 3% 5%0

5

10

15

20

2519.46

19.4619.46

19.46

0

20.13 20.71

10.13

0

19.82 20.39

8.7 PCCNPPPET


Com

pres

sive

stre

ngth

N/m

m²

Fig

4.6 Comparison between Compressive Strength of PCC, NPP & PET for 14

days

0% 1% 3% 5%0

5

10

15

20

25

30

35

25.46

31.36 31.4

20.4925.70

30.70

13.53 PETNPP


Com

pres

sive

stre

ngth

N/m

m²

Fig 4.7 Comparison between Compressive Strength of NPP & PET for 28 days

15

0% 1% 3% 5%0

5

10

15

20

25

30

35

25.46 25.46 25.46 25.46

0

31.36 31.4

20.49

0

25.7

30.7

13.53 PCCNPPPET


Com

pres

sive

stre

ngth

N/m

m²

Fig 4.8 Comparison between Compressive Strength of PCC, NPP & PET for

28 days

16

4.1.2 Flexural strength

It is the ability of a beam or slab to resist failure in bending. It is

measured by loading un- reinforced concrete beams with a span three times the

depth. Flexural strength is expressed as Mpa.

4.1.2.1 FLEXURAL STRENGTH OF PLAIN CEMENT

CONCRETE (PCC) BEAM

NPP= 0%

PET= 0%

Table 4.11 Flexural strength of plain cement concrete beam

Specimen Identity Flexural Strength

14 days (N/mm²)

Flexural Strength

28 days (N/mm²)

PCC 0% 2.728 5.437

PCC 0% 2.895 5.800

PCC 0% 2.665 5.357


4.1.2.2 FLEXURAL STRENGTH FOR 1% NPP REPLACEMENT17

NPP= 1% PET= 0%

Table 4.12 Flexural strength of NPP (1%) mixed concrete beam


14 days (N/mm²)

Flexural Strength

28 days (N/mm²)

NPP 1% 2.795 5.300

NPP 1% 3.012 6.005

NPP 1% 3.150 6.100


4.1.2.3 FLEXURAL STRENGTH FOR 3% NPP REPLACEMENT

NPP= 3% PET= 0%


Specimen Identity Flexural Strength 14 days (N/mm²)

Flexural Strength 28 days (N/mm²)

NPP 3% 2.673 5.950

NPP 3% 3.620 5.854

NPP 3% 2.795 5.900


4.1.2.4 FLEXURAL STRENGTH FOR 5% NPP REPLACEMENT

NPP= 5% PET= 0%

18



14 days (N/mm²)

Flexural Strength

28 days (N/mm²)

NPP 5% 2.360 4.725

NPP 5% 2.421 4.850

NPP 5% 2.364 4.730


Table 4.15 Flexural strength of NPP specimens


14 days (N/mm²)

Flexural Strength

28 days (N/mm²)PCC 2.762 5.530

NPP 1% 2.985 5.801

NPP 3% 3.029 5.901

NPP 5% 2.381 4.768

19

PCC NPP 1% NPP 3% NPP 5%0

1

2

3

4

5

6

7

2.762 2.985 3.029 2.381

5.530

5.801 5.901

4.768

28 DAYS14 DAYS

% Replacement of NPP

Flex

ural

Str

engt

h N

/mm

²

Fig 4.9 Flexural Strength of PCC & NPP

14 DAYS 28 DAYS0

1

2

3

4

5

6

2.762

5.53

2.985

5.801

3.029

5.901

2.381

4.417

PCCNPP 1%NPP 3%NPP 5%

Flex

ural

stre

ngth

N/m

m²

Fig 4.10 Comparison between Flexural Strength of PCC & PET

20

4.1.2.5 FLEXURAL STRENGTH FOR 1% PET REPLACEMENT

PET= 1% NPP= 0%

Table 4.16 Flexural strength of PET (1%) mixed concrete beam


14 days (N/mm²)

Flexural Strength

28 days (N/mm²)

PET 1% 2.695 5.502

PET 1% 2.675 5.525

PET 1% 2.950 5.569


4.1.2.6 FLEXURAL STRENGTH FOR 3% PET REPLACEMENT

PET= 3% NPP= 0%



14 days (N/mm²)

Flexural Strength

28 days (N/mm²)

PET 3% 2.669 5.350

PET 3% 2.785 5.937

PET 3% 2.935 5.401


4.1.2.7 FLEXURAL STRENGTH FOR 5% PET REPLACEMENT21

PET= 5% NPP= 0%



14 days (N/mm²)

Flexural Strength

28 days (N/mm²)

PET 5% 2.107 4.205

PET 5% 2.440 4.675

PET 5% 2.175 4.373


Table 4.19 Flexural strength of PET specimens


14 days (N/mm²)

Flexural Strength

28 days (N/mm²)PCC 2.762 5.530

PET 1% 2.773 5.532

PET 3% 2.796 5.562

PET 5% 2.240 4.417

22

PCC PET 1% PET 3% PET 5%0

1

2

3

4

5

6

2.762 2.773 2.796 2.24

5.530 5.532 5.562

4.417

28 DAYS14 DAYS

% Replacement of PET

Flex

ural

Str

engt

h N

/mm

²

Fig 4.11 Flexural Strength of PCC & PET

14 DAYS 28 DAYS0

1

2

3

4

5

6

2.762

5.53

2.773

5.532

2.796

5.562

2.24

4.76799999999999

PCCPET 1%PET 3%PET 5%

Flex

ural

Str

engt

h N

/mm

²

Fig

4.12 Comparison between Flexural Strength of PCC & PET

23

Table 4.20 Comparison between Flexural Strength of PCC, NPP & PET for

14 days and 28 days

Flexural Strength of PCC for 14 days= 2.762 N/mm²

Flexural Strength of PCC for 28 days= 5.530 N/mm²

Specimen

Identity

% Replacement of Recycled Plastic1% 3% 5%

14 days 28 days 14 days 28 days 14 days 28 days

NPP 2.985 5.801 3.029 5.901 2.381 4.768

PET 2.773 5.532 2.796 5.562 2.240 4.417

0% 1% 3% 5%0

0.5

1

1.5

2

2.5

3

3.5

2.7622.985 3.029

2.3812.773 2.796

2.240

PETNPP


Flex

ural

Str

engt

h N

/mm

²

Fig 4.13 Comparison between Flexural Strength of NPP & PET for 14 days

24

0% 1% 3% 5%0

0.5

1

1.5

2

2.5

3

3.5

2.762 2.762 2.762 2.762

0

2.985 3.029

2.381

0

2.773 2.796

2.24

PCCNPPPET


Flex

ural

stre

ngth

N/m

m²

Fig 4.14 Comparison between Flexural Strength of PCC, NPP & PET for

14 days

0% 1% 3% 5%0

1

2

3

4

5

6

7

5.53 5.801 5.901

4.767999999999995.532 5.562

4.417

PETNPP


Flex

ural

Str

engt

h N

/mm

²

Fig 4.15 Comparison between Flexural Strength of NPP & PET for 28 days

25

0% 1% 3% 5%0

1

2

3

4

5

6 5.53 5.53 5.53 5.53

0

5.801 5.901

4.76799999999999

0

5.532 5.562

4.417

PCCNPPPET


Flex

ural

Str

engt

h N

/mm

²

Fig 4.16 Comparison between Flexural Strength of PCC, NPP & PET for

28 days

26

CHAPTER 5

CONCLUSION

The project intended to find the effective ways to reutilize the plastic

waste particles as concrete aggregate. Analysis of the strength characteristics of

concrete containing recycled plastic gave the following results.

It is identified that plastic waste can be disposed by using them

as construction materials.

Since the Recycled Plastic is not suitable to replace fine

aggregate it is used to replace the coarse aggregate.

All these forms have smooth surface and hence require surface

roughening treatment for better bond characteristics.

From the results it can be concluded that the compressive

strength gradually increases as the percentage of replacement of

Natural Poly Propylene (NPP) by weight of coarse aggregate

also increase and attains a peak value at 3% replacement of NPP

with 18.91% increase in compressive strength.

Similarly the flexural strength of the NPP mixed concrete beam

seems to increase as the 3% of NPP replaced in concrete. The

maximum increase in flexural strength was found to be 6.28%.

Hence to achieve a high compressive strength and flexural

strength it is recommended that coarse aggregate can be

replaced with 3% of NPP by its weight.

27

performance study on recycled plastics in concrete

Engineering