““EFFECT OF VARYING EFFECT OF VARYING

MIXING & COMPACTION MIXING & COMPACTION

TEMPERATURE TEMPERATURE

ON MARSHALL PROPERTIES ON MARSHALL PROPERTIES

OF BC MIX”OF BC MIX”BySHIVA KUMAR.M.J

Under the Guidance

Of

Dr. KrishnamurthyProfessor – PG Studies

CONTENTSCONTENTS

INTRODUCTION

LITERATURE REVIEW

PRESENT INVESTIGATIONS

TEST RESULTS AND

OBSERVATIONS

DISCUSSIONS AND CONCLUSIONS

REFERENCES

IntroductionIntroduction The design of bituminous

mixture by Marshall Method involves the proportioning of the aggregates and bitumen to produce a mix that will have the optimum qualities and properties such as

1)stability, 2)durability and 3)flexibility,

based on the climatic condition, traffic density and loads it is intended to carry.

Factors affecting on property Factors affecting on property of bituminous mix are :-of bituminous mix are :-Proper selection of aggregate.Proper selection of bitumen.Proper specifications.Proper mix design. Other factors like Heating

Temperature & Mixing time.Temperature of Compaction &

type of Compaction.

Objective of present studyObjective of present study To study the effect of varying Mixing and

Compacting temperatures on Marshall

Properties of bituminous mix(Bituminous

concrete-II).

Marshall Moulds were prepared and each specimen

tested for the following:Bulk Specific Gravity, (Gb )

Air Voids, (VV )Voids in Mineral Aggregate, (VMA)Voids Filled with Bitumen, (VFB)Marshall Stability and Flow

Premix is one type of Hot mix

asphalt (HMA) widely used in road

construction worldwide.

Premix is most popular as paving

material such as BC,SDBC,DBM

etc… with

high skid resistance,

high comfortability and

low maintenance cost

The aggregate and asphalt will be

combined in an asphalt mixing

plant in which it will be

proportioned,

heated and

mixed to produce the desired

paving mixture at a standard

Mixing temperature.

The mix will be transported to site and

spread with paving machine in loosely

compacted layer to uniform , smooth

surface.

Then the mix will be compacted by

heavy roller within the standard

Compaction Temperature , To

produce smooth and well consolidated

course.

Standard Mixing & Compacting Standard Mixing & Compacting

Temperature for different grade of Temperature for different grade of

bitumen as per MoRT&Hbitumen as per MoRT&HBitumen

penetration

Bitumen

Mixing

Aggregate

Mixing

Mixed

material(°C)

(Maximum)

Laying

temp(°C)

(minimum)

Rolling temp

(°C)

(minimum)

35 160-170 160-175 170 130 100

65 150-165 150-170 165 125 90

90 140-160 140-165 155 115 80

Effect of temperature on Effect of temperature on bituminous pre-mix are :-bituminous pre-mix are :- Its effect on the mix constituents which

changes the viscosity and some of the properties of the aggregate which affect both the spreading and absorption of the bitumen.

Its effect on the mixing, laying and compaction operations as a result of these changes in the properties of the mix .

Surface layer has failed due to carelessness in maintaining proper temperature during mixing and compaction.

Causes for variation of Causes for variation of mixing Temperature:-mixing Temperature:-

Improper heating of bitumen.

Improper heating of aggregate.

Less mixing timing of drum mixer or batch mix plant

Lower mixing temperature means lower operating cost.

Running plant in rain and cold environment.

Causes for variation of Causes for variation of compaction Temperature:-compaction Temperature:-Maximum hauling distance of mix.

No Insulation to truck beds.

No Place a tarpaulin over the truck

bed.

Other factors like air temperature ,

wind velocity and humidity.

Effect of Improper Mixing or Effect of Improper Mixing or Compaction temperature Compaction temperature

Infrared picture of an HMA storage truck dumping HMA Infrared picture of an HMA storage truck dumping HMA showing showing the silo loading a truck showing showing the silo loading a truck cold cold surface layer crust(blue) and showing the hot uniform surface layer crust(blue) and showing the hot uniform the hot inner mass (red) the hot inner mass (red) temperature(>150temperature(>150⁰C)⁰C) of the mix. of the mix.

Red colour : >150Red colour : >150⁰C ⁰C Blue colour : 60-70Blue colour : 60-70⁰C⁰C

Driver covering his truck Driver covering his truck bed with a tarpaulinbed with a tarpaulin

Photos taken from University of Washington & Photos taken from University of Washington & National Center for Asphalt Technology(NCAT) National Center for Asphalt Technology(NCAT)

PRESENT INVESTIGATIONS

Constituents of Bituminous concrete grade-2 are:

Coarse aggregates:

Offer compressive and shear strength. Material retained on 2.36mm IS sieve

Fine aggregates: Fills the voids in the coarse aggregate. Material passing 2.36mm and retained on 0.075mm or

75 micron IS sieve Filler:

Fills the voids between the fine aggregates. Material should pass through 0.075mm or 75 micron IS

sieveFiller taken in present study is Cement.

Binder: Fills the voids, cause particle adhesion.(5)

Aggregate gradation for BC mix Aggregate gradation for BC mix Grade-2 as per MoRT&H table 500-Grade-2 as per MoRT&H table 500-1818

Grading 2

Nominal aggregate size 13mm

Layer thickness 30-45mm

I.S sieve(mm)Cumulative % by weight of

total aggregate passingMid limit

19

13.2

9.5

4.75

2.36

1.18

0.6

0.3

0.15

0.075

100

79-100

70-88

53-71

42-58

34-48

26-38

18-28

12-20

4-10

100

89.5

79

62

50

41

32

23

16

7Bitumen content by mass

of total mix5.0-7.0

Bitumen Grade (penetration)

65

Preliminary laboratory investigation:-

Following test has been done PHYSICAL PROPERTIES OF AGGREGATES

PHYSICAL PROPERTIES OF FILLERS

PHYSICAL PROPERTIES OF 60/70 GRADE

BITUMEN

MARSHALL PROPERTIES OF BC MIX

MARSHALL PROPERTIES AT OBTIMUM

BINDER CONTENT FOR MID LIMIT

GRADATIONS

PHYSICAL PROPERTIES OF PHYSICAL PROPERTIES OF AGGREGATESAGGREGATES

Sl. No. PropertyMoRT&H

specificationResults

1. Specific gravity

i) Coarse aggregate

ii) Fine aggregate2.5-3

2.65

2.71

2. Aggregate impact value Max 24% 25.18 %

3. Los Angeles abrasion value Max 30% 28.76 %

4.Flakiness & Elongation index

(combined)Max 30% 31.80%

5. Water absorption Max 2% 0.5 %

6.Stripping value (coating of

bitumen retained)Min 95% 99 %

PHYSICAL PHYSICAL PROPERTIESPROPERTIES OF OF FILLERSFILLERS

Sl. No. Material Results

1. Cement 3.01

2. Quarry Dust 2.77

PHYSICAL PROPERTIES OF 60/70 GRADE PHYSICAL PROPERTIES OF 60/70 GRADE

BITUMENBITUMEN

SI

No.Property Value

Requirements as per

IS: 73-2002

1 Penetration at 25°C 66 60-70

2Softening point

(R&B) (°C)51 45-55

3 Ductility @27°C cm 100+ 75 min

4 Specific Gravity 0.9944 0.99

MARSHALL TEST RESULTS AT 60°C FOR 60/70 MARSHALL TEST RESULTS AT 60°C FOR 60/70

GRADEGRADE

BITUMEN AT STANDARD MIXING TEMPERATURE OF BITUMEN AT STANDARD MIXING TEMPERATURE OF

160°C AND COMPACTING TEMPERATURE OF 149°C160°C AND COMPACTING TEMPERATURE OF 149°C

Bitumen

Content

(%)

Marshall

Stability kg

Flow Value,

mm

Bulk Density

(Gb)

g/cm3

Total Air

Voids (Vv)

%

Voids filled

with Mineral

Aggregate

(VMA)

%

Voids filled

with

Bitumen

(VFB)

%

5.00 1561 3.122.360 5.744 17.314 66.833

5.50 1904 3.632.377 4.426 17.244 74.333

6.00 1852 3.832.374 3.902 17.869 78.211

6.50 1581 4.502.371 3.388 18.500 82.214

GRAPHS OF BC MIXES USING 60/70 GRAPHS OF BC MIXES USING 60/70 GRADE GRADE BITUMEN TO DETERMINE OBC BITUMEN TO DETERMINE OBC

MARSHALL PROPERTIES AT OBTIMUM MARSHALL PROPERTIES AT OBTIMUM BINDER CONTENT FOR MID LIMIT BINDER CONTENT FOR MID LIMIT GRADATIONS OF BC USING 60/70 GRADE GRADATIONS OF BC USING 60/70 GRADE BITUMEN AT 60°CBITUMEN AT 60°C

Marshall PropertiesResults of BC, Grade - II mix Requirements as per

MoRT&H Specifications

Optimum Binder Content, % 5.70 Min 5 %

Marshall stability at 60°C kg1919 900

Flow Value, mm 3.70 2 to 4

Bulk Density, g/cm3 2.38 ----

Air Voids, (Vv) % 4.547 3 to 6

VMA, % 17.78 14

VFB, % 74.427 65 to 75

Effect of varying Mixing & Effect of varying Mixing & Compacting Temperature on Compacting Temperature on Marshall Properties:-Marshall Properties:-

For 60/70 grade bitumen ,

The maximum mixing temperature is 165°C and

Minimum compaction temperature is 90°C as

per MoRT&H.

For the present study we varied mixing

temperature 130°C, 157.5°C & 180°C and also

we varied compaction temperature 70°C ,

90°C,110°C& 130°C.

Marshall Properties by Marshall Properties by keeping Constant keeping Constant

Mixing Temperature of Mixing Temperature of 130°C 130°C and and

by varying Compaction by varying Compaction temperature for temperature for

Bituminous Concrete Bituminous Concrete Mix Mix

Marshall

propertiesResults at varying Compaction temperature

Requirement as

per MoRT&H

Temperature(°C) 70°C 90°C 110°C 130°C

Blow 75 75 75 75 75

Optimum

Binder

Content (%)

5.70 5.70 5.70 5.70 5-7

Stability (kg) 930 1124 1282 1458 900

Flow (mm) 2.90 3.40 3.75 4.40 2-4

Bulk

Density(g/cc)2.242 2.293 2.332 2.376 -----------

Total air voids,

Vv %9.614 7.550 5.987 4.321 3-6

VMA, % 22.143 20.366 19.019 17.506 13

VFB,% 56.588 62.944 68.523 75.929 65-75

Observation made from test and Observation made from test and tabletable Bitumen is having high viscosity thereby

Mixing (i.e. Workability) is difficult at 130°C

temperature and high total air voids.

Bulk Specific gravity value at mixing

temperature 70°C, 90°C, 110°C and 130°C

were found to be 2.242, 2.293, 2.332 and

2.376.

Stability value at mixing temperature 70°C,

90°C, 110°C and 130°C were found to be 930,

1124, 1282 and 1458.

Marshall Properties by Marshall Properties by keeping Constant keeping Constant

Mixing Temperature of Mixing Temperature of 157.5°C 157.5°C

and and by varying Compaction by varying Compaction

temperature for temperature for Bituminous Concrete Bituminous Concrete

Mix Mix

Marshall

propertiesResults at varying Compaction temperature

Requirement as

per MoRT&H

Temperature(°C) 70°C 90°C 110°C 130°C

Blow 75 75 75 75 75

Optimum

Binder

Content (%)

5.70 5.70 5.70 5.70 5-7

Stability (kg) 1264 1617 1850 1899 900

Flow (mm) 3.25 3.55 3.85 4.30 2-4

Bulk

Density(g/cc)2.335 2.372 2.394 2.394 -----------

Total air voids,

Vv %5.861 4.358 3.501 3.497 3-6

VMA, % 18.910 17.616 16.878 16.874 13

VFB,% 69.012 75.263 79.310 79.279 65-75

Observation made from test and Observation made from test and tabletable Bulk Specific gravity value at compaction

temperature 70°C, 90°C, 110°C and 130°C were

found to 2.335, 2.372, 2.394 and 2.394.

Stability value at compaction temperature 70°C,

90°C, 110°C and 130°C were found to be 1264,

1617, 1850 and 1899, which gives maximum

stability

With the increase in compaction temperature from

70 to 130°C degrees the air voids are reduced by

5.861,4.358,3.501 and 3.497% respectively, Due to

reduction in air voids there is increase in VFB

Marshall Properties by Marshall Properties by keeping Constant keeping Constant

Mixing Temperature of Mixing Temperature of 180°C 180°C and and

by varying Compaction by varying Compaction temperature for temperature for

Bituminous Concrete Bituminous Concrete Mix Mix

Marshall

propertiesResults at varying Compaction temperature

Requirement as

per MoRT&H

Temperature(°C) 70°C 90°C 110°C 130°C

Blow 75 75 75 75 75

Optimum

Binder

Content (%)

5.70 5.70 5.70 5.70 5-7

Stability (kg)1101 1151 1588 1619

900

Flow (mm)3.25 3.70 4.25 4.40

2-4

Bulk

Density(g/cc)

2.326 2.356 2.373 2.387-----------

Total air voids,

Vv %

6.227 5.034 4.338 3.7743-6

VMA, %19.226 18.198 17.599 17.113

13

VFB,%67.618 72.346 75.349 77.982

65-75

Observation made from test and Observation made from test and tabletable Bitumen losses its physical properties

(rheological property) at high temperature of 180°C therefore less stability and bulk density compared to mixing temperature 157.5 °C

Bulk Specific gravity value at compaction temperature 70°C, 90°C, 110°C and 130°C were found to 2.326, 2.356, 2.373 and 2.387.

Stability value at compaction temperature 70°C, 90°C, 110°C and 130°C were found to be 1101, 1151, 1588 and 1619.

DISCUSSIONS AND DISCUSSIONS AND CONCLUSIONSCONCLUSIONS Results of physical properties of the

aggregates used are satisfying the

requirements as per Table 500-17 of

MoRT&H (IV Revision) specifications.

Results of physical properties of the Plain

binder used are satisfying the requirements

as per IS: 73-1992 for plain bitumen.

From Marshall Mix design, optimum bitumen

content is 5.7% for a Bituminous Concrete

mix and it was meeting the requirement as

per the MoRT&H IV revision specifications

Table 500-18 & Table 500-19.

CONCLUSIONCONCLUSION Flow of the mix reduces with reduction in Mixing &

Compaction temperatures. The workability of the mix

will reduce in the field.

Stability will increase as the increase in Mixing &

Compaction temperature up to certain level.

If there is increase in air voids, which will increase the

cracks and there will be undulations on the surface

(wearing) course.

Voids filled with bitumen will increase, due to increase

in mixing temperature & compaction temperatures.

Voids in mineral aggregate(VMA) decreases with the

increase in compaction temperature.

RECOMMENDATIONRECOMMENDATION

The ideal mixing temperature for BC

grade-2 comes out to be 157.5°C (i.e. in

between 150 to 165°C)

The Ideal compaction temperature for BC

grade-2 comes out to be 110°C & 130°C

as per results of this study.

Transportation of BC MIX should have

Minimize haul distance , Insulate truck

beds and Place a tarpaulin over the truck

bed

REFERENCESREFERENCES1) Larry AK Silas Tirau, "Evaluation of Hot Mix

Asphalt (HMA) properties compacted at various temperatures", project report, November-2005.

2) Dr.H.C.Mehndiratta & Praveen Kumar , “Effect of Mixing and Compacting temperatures on Marshall parameters of bituminous mixes”.

3) Khanna.S.K., And Justo.C.E.G, "Highway material testing Manual“.

4) Khanna.S.K., And Justo.C.E.G, "Highway Engineering”

5) Specifications of Road and Bridge Works Ministry of Road Transport and Highways (MoRT&H), Govt of India, Fourth Edition, 2001

Thank youThank you