Effect of the use of crumb rubber in conventional bitumen on the marshall stability value

IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
__________________________________________________________________________________________
Volume: 03 Issue: 01 | Jan-2014, Available @ http://www.ijret.org 209
EFFECT OF THE USE OF CRUMB RUBBER IN CONVENTIONAL
BITUMEN ON THE MARSHALL STABILITY VALUE
Harpalsinh Raol1
, Abhijitsinh Parmar2
, Dhaval Patel3
, Jitendra Jayswal4
1
Scholar, Transportation Engineering, GEC Modasa, Gujarat, India
2
Assistant Professor, SVBIT, Gandhinagar, Gujarat, India
3, 4
Scholar, WRM Engineering, LDCE, Gujarat, India
Abstract
In today’s era, solid waste management is the thrust area. Out of this various waste materials, plastic waste, tyre waste and municipal
solid waste are of great concern. On the other side, the road traffic is increasing. The traffic intensity isalso increasing. The load
bearing capacities of the road are to be increased. Our present work is helping to take care of both these aspects.Plastic waste,
consisting of carry bags, cups, thermocoles, etc. can be used as a coating over aggregate and this coated stone can be used for road
construction. Secondly the waste tires are powdered and the powder is blended with bitumen and this blend is used along with plastic
coated aggregate. The mix polymer coated aggregate and tyre modified bitumen have shown higher strength. Use of this mix for road
construction helps to use both plastics waste and tyre waste.Stone aggregate is coated with the molten waste plastics. The coating of
plastics reduces the porosity, absorption of moisture and improves soundness.The polymer coated aggregate bitumen mix forms better
material for flexible pavement construction as the mix shows higher Marshall Stability value and suitable Marshall Coefficient.
Moreover the polymer coated aggregate helps to use Crumb rubber modified bitumen resulting in better result. Moreover the polymer
coated aggregate helps to use Crumb rubber modified bitumen resulting in better result.Crumb Rubber Modified Bitumen (CRMB) is
hydrocarbon binder obtained through physical and chemical interaction of crumb rubber (produced by recycling of used tires) with
bitumen and some specific additives. The Flextal range of CRMB offers binders which are stable and easy to handle with enhanced
performances.( www.total.co.in)[1]
Keywords:CRMB, Pavement, Bitumen, Crumb Rubber, and Marshall Stability Value
----------------------------------------------------------------------***------------------------------------------------------------------------
1.INTRODUCTION
The most dominant mode of the transport in India is the Road
Transport, carrying close to 90% of the passenger traffic &
70% of the freight transport. In India, flexible pavement type
of construction is preferred over the rigid pavement type of
construction due to its various advantages such as low initial
cost, maintenance cost, etc.Therefore, among the surfaced
roads, maximum is the contribution of the bituminous
pavements. In spite of the prominence of the surface transport,
most of the roads are poorly managed and badly
maintained.Bitumen is used as binder & water proofing
material for construction of roads, pavements & air field
surfacing for several years .The demand of bitumen has
increased tremendously because of rapid urbanization in
recent years. The objective can be achieved by enhancing the
durability of existing road surfacing which will result in
reducing maintenance & resurfacing operations.
Hence, the modification of bitumen to meet the required
performance standards of the pavement appears to be logical
& economical approach. Bituminous pavement fails to give
the expected service life under adverse climate,
environmental& traffic conditions.The use of crumb-rubber in
bitumen modification helps in achieving better performance of
wearing courses.
The advantages of modified bitumen can include one or more
of the following for road works.
 Lower susceptibility to daily & seasonal temperature
variations.
 Higher resistance to deformation at elevated
pavement temperature.
 Better age resistance properties.
 Higher fatigue life of mixes.
 Better adhesion between aggregates & binder.
 Prevention of cracking & reflective cracking.
 Overall improved performance in extreme climatic
conditions & under heavy traffic conditions.
2.OBJECTIVE
The advantages of modified bitumen can include one or more
of the following for road works.
 Lower susceptibility to daily & seasonal temperature
variations.
 Higher resistance to deformation at elevated
pavement temperature.

__________________________________________________________________________________________
 Better age resistance properties.
 Higher fatigue life of mixes.
 Better adhesion between aggregates & binder.
 Prevention of cracking & reflective cracking.
 Overall improved performance in extreme climatic
conditions & under heavy traffic conditions.
3.DESIGN STEPS
Mixing of crumb rubber and bitumen mix
↓
Preparation of Bituminous Mix
↓
Marshall Stability test on the mix
4. MATERIALS
Table -1: Materials required for CRMB mix
Sr. No. Material Content
1 Bitumen 5-5.5%
2 Aggregates 75-90%
3 Crumb Rubber(30 mesh) 5%,10%,15%,20%
5. TEST
Before preparing the specimens for Marshall Test, it is
required that following steps.
 Material proposed for use the gradation requirements
of the project specifications.
 The blend combinations meet the gradation
requirements of the project specifications.
 Therefore use in density and voids analysis the pulse
specific gravity of all aggregate used in the blend
and the specific gravity of asphalt are determined.
Two principle feature of the Marshall method of mix design
are density-voids analysis and stability-flow test of the
compacted test specimens. The stability of test specimen is the
maximum load resistance in Kg. that the standard test
specimen will develop at 600C when tested. The flow is the
total movement or strain occurring in the specimen between
no load and maximum load during the stability test. In
determining the bitumen content for a particular blend or
gradation of aggregate triplicate specimen are prepared over a
range of different bitumen contents (For conventional bitumen
5% to 6% and for modified bitumen 4.5% to 5.5%). So that
one is above the optimum and one is below the optimum
content. Aggregate needed is about 1250 gm for each test.
5.1 Equipment Needed
 Pans for heating aggregates.
 Pans for mixing bitumen and aggregates.
 Electric oven for heating aggregate.
 Contains for handling bitumen and aggregates.
 Thermometer.
 Balance of 5 Kg. and 2 Kg. capacities.
 Mixing spoon.
 Spatula.
 Water bath for heating compaction hammer and
mould.
 Electrically operated compactor with all accessories.
 Extrusion jack.
 Water bath at 600C.
 Gloves.
5.2 Specimen Preparation
(1) Number of Specimen: At least three specimens are
prepared for each combination of aggregates and bitumen
content.
(2)Preparation of aggregate: Aggregates are dried to
temperature at 1050C – 1100C and separation by dry sieving
into desired size fractions.
(3) Sieve analysis of aggregates: Numbers of trials are done
to fix the proportion of different aggregate by sieve analysis.
This portion is very important in bitumen mix design.
(4) Preparation of mixing and compaction temperature:
Bitumen is heated to about 1350C to 1450C so that the water
vapor present in it is evaporated & aggregates are heated to
about 170˚C-175˚C. Bitumen is mixed thoroughly with
aggregates by manually or mechanically.
(5) Preparation of mould and hammer: Specimen mould
and compaction hammer are cleaned thoroughly and mould
assembly is heated in hot air oven to a temperature of about
1500C. A little grease is applied to the mould before the mix is
placed in the mould.
(6) Preparation of Specimen: The amount of each size of
fraction required to produce a mixed aggregate of 1200 gm. as
per gradation is weighted. The required height of specimen is
63.5±1 mm. aggregate and bitumen is heated separately to the
require temperatures. Then bitumen is poured in aggregate as
per requirement. Then mixture is mixed till a uniform coating
of bitumen is obtained on aggregate. This is obtained at about
1500C.
(7) Compaction of the Specimen: Mould is assembled and a
little grease is applied to it. Mix is transferred into 3 layers and
each layer being tamped with spatula by 25 times. Then 75
blows are applied through manually or electrically operated
compactor. Then same numbers of blows are applied on the
other side of mould. Then the specimen is allowed to cool,
once the specimen comes to room temperature de-mould is
carried out.
(8) Application of water bath: Before testing mould on
Marshall Apparatus, the moulds are followed to keep in the
water bath for 30 to 40 minutes at 600C. Mould should be
tested within 3 to 4 minutes after taken out from water bath.
(9) Basic parameters of Marshall Test: Mould is put out on
Marshall Apparatus and Marshall Stability as well as Marshall
Flow is measured by proving ring and flow dial gauge
respectively. The minimum value of proving ring is 1 division

__________________________________________________________________________________________
= 0.01 mm and flow dial gauge 1 division = 0.25 mm. the
correction factor is depends on capacity of Marshall
Apparatus.
After this, the other parameters like Unit Weight (gm/cc),
Specific Gravity of mix (Gmm), Air Voids (%), Voids in
mineral aggregates (%), Voids filled with bitumen (%), etc.
are calculated by derived formulas.[2]
Fig -1: Marshall Stability Apparatus.
Source of figure (www.asphalttestinginstruments.com)
6. TEST RESULTS
Result table is provided after biographies.
Fig 2: Marshall Stability (kg) Vs Bitumen (%)
Fig 3: VFB (%) Vs Bitumen (%)
Fig 4: Flow VFB (%) Vs Bitumen (%)
Fig 5: Air Voids (%) Vs Bitumen (%)
1086.414
1615.843
1402.43
1022.507
900
1000
1100
1200
1300
1400
1500
1600
1700
3.75 4 4.25 4.5 4.75 5 5.25
MarshallStability
Bitumen (%)
74.89
75.25
76.65
78.82
72
73
74
75
76
77
78
79
80
3.75 4 4.25 4.5 4.75 5 5.25
VFB(%)
Bitumen (%)
2.53
2.8
3.02
3.5
2.25
2.5
2.75
3
3.25
3.5
3.75
3.75 4 4.25 4.5 4.75 5 5.25
FlowValue(mm)
Bitumen (%)
4.23
4.135
3.925
3.45
3.2
3.4
3.6
3.8
4
4.2
4.4
3.75 4 4.25 4.5 4.75 5 5.25
Airvoids%
Bitumen (%)

__________________________________________________________________________________________
Fig 6: Bulk Density (gm/cc) Vs Bitumen (%)
CONCLUSIONS
Crumb rubber gives the satisfactory results by using it in 15%
of proportion to replace the bitumen for various tests of
bitumen & bitumen mix.Crumb rubber gives the Marshall
Stability value of 1615.84 kg by using 15% of crumb rubber
powder with bitumen mix, which is 1.6 times greater than the
Marshall Stability value of conventional bitumen mix.
REFERENCES
[1]. http://www.total.co.in/pro/bitumen-home/bitumen-for-
roads/crumb-rubber-modified-bitumen.html
[2]. Marshall Procedures for Design and Quality Control of
Asphalt Mixtures. Asphalt Paving Technology: Proceedings,
vol. 54. Association of Asphalt Paving Technologists
Technical Sessions, 11-13 February 1985. San Antonio, TX.
pp. 265-284.
[3]. http://www.asphalttestinginstruments.com
BIOGRAPHIES
I, Harpalsinh Raol, is currently pursuing my
master degree in Transportation engineering
from GEC Modasa. I have done my degree
engineering from SPCE Visnagar. I am in a
constant endeavor to enhance my knowledge in
the field of transportation engineering.
I, Abhijitsinh Parmaris currently working as a
Head and assistant Professor at
ShankersinhVaghelaBapu Institute of
Technology. I have Completed M.Tech in
Structural Design from CEPT University
I, Jitendra Jayswal, is currently pursuing my
master degree in Water Resource engineering
from LDCE. I have done my degree
engineering from SPCE Visnagar. I am in a
constant endeavor to enhance my knowledge
in the field of Water Resource management.
I, Dhaval M Patel, is currently pursuing my
master degree in Water Resource engineering
from LDCE.
2.534
2.547
2.556
2.52
2.5
2.51
2.52
2.53
2.54
2.55
2.56
2.57
3.75 4 4.25 4.5 4.75 5 5.25
Bulkdensity(Gmb)gm/cc
Bitumen (%)

__________________________________________________________________________________________
Table -2: Marshall Stability test result of CRMB
Sr. No.
Crumb
Rubber
%
Bitumen
%
Density
(Gmb)
Maximum
theoretical
Specific
Gravity
(Gmm)
Air
void %
VMA
%
VFB
%
Corrected
Stability
(kg)
Flow
(mm)
1
0
5 2.52 2.61 3.45 16.29 78.82 1022.507 3.5
2 10 4.5 2.556 2.62 3.925 16.80 76.65 1402.43 3.02
3 15 4.25 2.547 2.632 4.135 16.49 75.25 1615.84 2.8
4 20 4 2.534 2.645 4.23 16.23 74.89 1086.41 2.53

Effect of the use of crumb rubber in conventional bitumen on the marshall stability value

More Related Content

What's hot (20)

Viewers also liked (18)

Similar to Effect of the use of crumb rubber in conventional bitumen on the marshall stability value (20)

More from eSAT Journals (20)

Recently uploaded (20)

Effect of the use of crumb rubber in conventional bitumen on the marshall stability value