Waste Plastic Modified Bitumin

Adhesion Characteristics Study On Waste Plastics Modified Bitumen

ADHESION CHARACTERISTICS STUDY ON WASTE PLASTICS MODIFIED BITUMEN

By

MOHAMMED IMTHIYAZ M.A (M.Tech Highway Technology, B.E Civil) D.S.C.E Bangalore-78 1

Adhesion Characteristics Study On Waste Plastics Modified Bitumen

1. INTRODUCTION 1.1 GENERAL One of the principal functions of a bituminous binder is, as its name suggests, acting as an adhesive either between road and underlying road surface. Bitumen can be regarded as an ideal adhesive but, in general, when proper precautions are exercised to adequate. There are occasions, however, when the adhesive bond may fail and the durability of the bituminous material may be seriously affected. The bonding between bitumen and aggregate is of special importance because it is the primary characteristic that influences the integrity of the pavement. This bonding must be established at the initial stages of contact between the bitumen and the aggregate and must endure during the life time of the pavement. The adhesion of bituminous binders to road stone presents few problems in the absence of water, although excessive dust may create trouble. On the other hand, because road stones are wetted more easily by water than by a bituminous binder, the presence of water can lead to difficulties, either in the initial coating of damp or wet road stone or in maintaining an adequate bond between the binder and the stone. Failure of a bond already formed is commonly referred to as ‘stripping’, which is brought about by the displacement of the bituminous binder from the stone by water. It is desirable that there should be a reliable method of determining in the laboratory whether or not a bituminous binder will adhere well to an aggregate in the presence of water. Studies of the physico-chemical properties to lead to the development of a reliable method for the routine testing of bituminous materials, which is based on measurements of the fundamental properties of the system. It has therefore been necessary to develop arbitrary tests, which have may be used to examine the various combinations of road stones and binder used in bituminous construction. Such test may also used to study the effect of a particular variable behavior of the binder and aggregates. 2

Adhesion Characteristics Study On Waste Plastics Modified Bitumen

Numerous tests have been described most of which fall into six basic types. They are static immersion test, dynamic immersion, chemical immersion test, immersion mechanical test, immersion trafficking test and vialit test. The sixth test different in principle, that is an attempt is made to coat stone with binder in the presence of water. In this case the degree of coating is used as the index of adhesivity. 1.2 VIALIT AS AN ADHESION TEST Apparatus and materials required : 1. Steel plate of size 200mm x 200mm. 2. 100 chips of aggregate passing 19mm IS sieve and retained on 12.5mm IS sieve. 3. Steel ball weighing 500gms. 4. Rubber roller weighing 25kg. 5. Bitumen 60/70 6. Plastics. 7. Thermometer Procedure : 1. Weigh 100g of bitumen binder and heated up to pouring temperature of 75°C to 100 °C. 2. The bitumen sample is spreaded on 200mm x 200mm size of steel plate and then kept in water bath for cooling. 3. The binder is covered with 100 chips of aggregates passing 19mm IS sieve and retained on 12.5mm IS sieve and rolled six times perpendicularly and three times parallely with a rubber cylinder weighing 25kg. 4. The gravel plate is maintained at room temperature and it is placed in water bath for 20minutes. 5. The plate is then inverted on to a tripod and a steel ball weighing 500g is dropped from a height of 50cm. 6. The number of chips which fall are not coated at all with binder, the number of chips which fall and are partially coated with binder and the number of chips which adhere are collected and recorded. 3

Adhesion Characteristics Study On Waste Plastics Modified Bitumen

The value of adhesion index (AI) is expressed as AI = (b+c)/a AI = d/a Where a = the number of chips which fall are not coated at all with binder. b = the number of chips which fall and are partially coated with the binder c = the number of chips which adhere d = sum of b and c

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Adhesion Characteristics Study On Waste Plastics Modified Bitumen

2. WASTE PLASTIC MODIFIED BITUMEN 2.1 Desirable properties of modifiers-rubber and polymer:Polymer and rubber modified bitumen, often abbreviated as modified bitumen is obtained with the incorporation of selected thermoplastics and powdered rubber from discarded truck tires, natural rubber or any other suitable elastomers in bitumen. When used as bitumen modifier, selected polymers/rubber or blend of these should have the following properties.  Be compatible with bitumen.  Resist degrading of bitumen at mixing temperature.  Be capable of being processed by conventional mixing and laying machinery.  Produce coating viscosity at application temperature.  Maintain premium properties during storage, application and in service.  Be cost effective on a life cycle cost basis. Polymers are being increasingly used to modify bitumen and to enhance the properties of bituminous mixes. The polymer modified binder are highly suitable for special applications, where traffic is extremely high, climatic and mixing temperature play important role in the preparation of polymer modifier binder. Some of the polymers which are compatible with bitumen and which are easily available in market are styrene-butadiene-styrene (SBS), styrene-butadiene-rubber (SBR) and ethylene vinyl acetate (EVA). The mix prepared with these modifiers shows a higher resistance to permanent deformation at higher temperature, increased fatigue life, improved temperature susceptibility and reduced cracking potential at lower temperature compared to the conventional bitumen. The modified bitumen and the mixes prepared out of these modified bitumen should posses’ better strength characteristics compared to the mixes with plain bitumen. This aspect is studied in the present investigation.

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Adhesion Characteristics Study On Waste Plastics Modified Bitumen

3. PRESENT INVESTIGATION Plastics supplied from KK Plastics were tested for the adhesion with aggregates and bitumen. Care was taken to see that they were clean, free from dust vegetable matter, organic or other deletrious matter. Aggregate used is granite based which is supplied from the local quarry. Aggregate used is 20mm down size aggregate sieved with IS 19mm and retained with 12.5mm IS sieve. Sampling was done and angular aggregates were taken for the test.

Materials used : 1. Plastic coated with aggregates (PCA) 2. Waste plastics modified bitumen (WPMB) Plasitc Coating with Aggregates (PCA) Plastics heated up to melting point i.e 170°C and aggregate is mixed till the plastic is coated to the surface. Waste Plastic modified bitumen ( WPMB) Plastics heated up to melting point 170°C and heated bitumen is mixed by stirring till it is thoroughly blended. These two materials are blended with plastics, with increments of 2% from ( 0 to 14 )%. Tests conducted on these materials and data collected are anlaysed.

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Adhesion Characteristics Study On Waste Plastics Modified Bitumen

Figure 1. Plastic coated with aggregate .

Figure 2. The bitumen is covered with 100 chips of aggregate

Figure 3. The graveled plate is rolled six times perpendicularly and three times parallely with cylinder.

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Adhesion Characteristics Study On Waste Plastics Modified Bitumen

Figure 4. The graveled plate is placed in water bath for cooling.

Figure 5. The plate is inverted on tripod and steel ball weighing 500g is dropped from a height of 50cm

Figure 6. The number of chips which adhere are shown.

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Adhesion Characteristics Study On Waste Plastics Modified Bitumen

4.0 ANALYSIS OF DATA The laboratory investigation of adhesion of bitumen on PCA and WPMB results are tabulated below. Table -1 ( PCA) Type of binder – 60/70 Weight of binder- 100gms Sl. No 1 2 3 4 5 6 7 8

Plastic ( %)

a

b

c

AI= (b+c)/a

0 2 4 6 8 10 12 14

1 1 1 34 78 75 7 14

3 3 5 31 20 24 5 27

96 96 94 35 2 1 88 59

99 99 99 1.94 0.28 0.33 13.29 6.14

GRAPH : %OFPLASTIC VS ADHESION INDEX 120 100 80 60 40 20 0 0

2

4

6

8

10

12

14

16

%OF PLASTIC

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Adhesion Characteristics Study On Waste Plastics Modified Bitumen

Table -2 (WPMB) Type of binder – 60/70 Weight of binder- 100gms Sl.No

Plastic( %)

a

b

c

AI= (b+c)/a

1 2 3 4 5 6 7 8

0 2 4 6 8 10 12 14

2 4 3 2 8 2 2 3

4 3 3 3 2 2 1 1

92 93 94 95 91 96 97 96

48 24 32.3 49 11.63 49 49 32.33

GRAPH: %OFPLASTICVS ADHESIONINDEX 60 50 40 30 20 10 0 0

2

4

6

8

10

12

14

16

%OF PLASTIC

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Adhesion Characteristics Study On Waste Plastics Modified Bitumen

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CONCLUSION AND DISCUSSION 1. It is very difficult to uniformly coat the plastics to aggregates. Where as, it is easy to blend with bitumen. 2. Use of adhesion agent will be usefull in road works as it improves the adhesion property of aggregates. 3. Increasing the temperature of aggregates and steel plate responsible for the increase of adhesion of bitumen. 4. The weight of bitumen taken for 100 chips of aggregates also influence the adhesion of bitumen. 5. From the present investigation WPMB have more adhesion compared to PCA.

REFERENCE : 1. DISR, “ Bituminous Road Materials” H.M.S.O,London. 2. Khanna,S.K. and Justo,C.E.G. “ HIGHWAY ENGINEERING” Nem Chand & Brothers,Roorke,Eight Edition 2001. 3. MORTH. “Specification for Road and Bridge Works” IRC, (4th Revision) New Delhi, 2001.

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