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AggregateAggregate

Sieve No. 4 ( 4.75 mm)Sieve No. 4 ( 4.75 mm)

Coarse Aggregate

Fine Aggregate

Permanent

Deformation

Fatiguecracking

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11--Consensus RequirementsConsensus Requirementsa) Coarse Aggregate Angularity

Min requirement forone fractured faces

Min requirement forTwo or more

fractured facesSORBSORB\\R9 :R9 :-- Fractured Degree notFractured Degree not

Less than 70 % forLess than 70 % for aggagg..Retaining in sieve No.4Retaining in sieve No.4

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b) Fine Aggregate Angularity

AASHTO T 304AASHTO T 304:Uncompacted VoidContent of Fine

Aggregate

100*samplectedin Uncompavoidsof% sandofGSp.W-V

V=

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c) Flat or Elongated Particles ASTM D 4791ASTM D 4791

d) Clay Content

Sand Equivalent test

SORBSORB\\ R9 =BS 12, part 3R9 =BS 12, part 3

Flat factor Max. 15 %Flat factor Max. 15 %Elongation Factor Max. 25 %Elongation Factor Max. 25 %

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22--Source Aggregate RequirementsSource Aggregate Requirementsa) Toughness Aggregate Angularity

AASHTO T 96AASHTO T 96ASTM C 131ASTM C 131

ASTM C 535ASTM C 535L o s A n g e l e s A b r a s io n Te s t L o s A n g e l e s A b r a s i o n Te s t

SORBSORB\\R9R9

Surface layer Max. 30 %Surface layer Max. 30 %

SubbaseSubbase layer Max. 35 %layer Max. 35 %Base layer Max. 40 %Base layer Max. 40 %

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b) Soundness Test AASHTO T 104AASHTO T 104

ASTM C 88ASTM C 88

So u n d n e ss is t h e p e r c en t l o s s o f m a t e r i a l f r o m a nSo u n d n e ss is t h e p e r c en t l o s s o f m a t e r i a l f r o m a n a g ga g g..

B le n d d u r i n g t h e so d i u m o r m a g n e s i u m su l f a t e t e s t B le n d d u r i n g t h e so d i u m o r m a g n e s i u m su l f a t e t e s t

SORB/R9 not greater than 12 %.SORB/R9 not greater than 12 %.

SHRP not greater than 20 %.SHRP not greater than 20 %.

c) Deleterious Materials Test

SHRP not greater than 25 %.SHRP not greater than 25 %.AASHTO T 112AASHTO T 112

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Aggregate Size DefinitionsAggregate Size Definitions

Nominal MaximumNominal Maximum Aggregate SizeAggregate Size

one size larger than the first sieveone size larger than the first sieve

to retain more than 10%to retain more than 10%

MaximumMaximum Aggregate SizeAggregate Size

one size larger than nominalone size larger than nominalmaximum sizemaximum size

100100100100

9090

7272

6565

4848

3636

2222

1515

99

44

1001009999

8989

7272

6565

4848

3636

2222

1515

99

44

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100100

Percent PassingPercent Passing

00

.075.075 .3.3 2.362.36 4.754.75 9.59.5 12.5 19.012.5 19.0

Sieve Size (mm) Raised to 0.45 PowerSieve Size (mm) Raised to 0.45 Power4.75 mm sieve plots at(4.75)4.75 mm sieve plots at(4.75)0.450.45=2.02=2.02

Control PointControl Point

Restricted zoneRestricted zoneMax Density LineMax Density Line

MaxMax

sizesize

NomNom

maxmax

sizesize

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Superpave Aggregate GradationSuperpave Aggregate Gradation

100100

00

.075.075 .3.3 2.362.36 12.512.5 19.019.0

Percent PassingPercent Passing

Design Aggregate StructureDesign Aggregate Structure

Sieve Size (mm) Raised to 0.45 PowerSieve Size (mm) Raised to 0.45 Power

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Superpave Mix SizeSuperpave Mix Size

DesignationsDesignations

SuperpaveSuperpave Nom Max SizeNom Max Size Max SizeMax SizeDesignationDesignation (mm)(mm) (mm)(mm)

37.5 mm37.5 mm 37.537.5 5050

25 mm25 mm 2525 37.537.5

19 mm19 mm 1919 2525

12.5 mm12.5 mm 12.512.5 1919

9.5 mm9.5 mm 9.59.5 12.512.5

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2 3 4 5 6 789 2 3 4 5 6 7 89 2 3 4 5 6 789 2 3 4 5 6 7 89

0 0 1 10 100

Sieve size

0

10

20

30

40

50

60

70

80

90

100

%Passing

SORP R9/3

Nominal Max. Size of Agg. 3/4 "

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VolumetricVolumetric CalculationCalculation

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Asphalt Content (Asphalt Content (PPbb)) is the total asphalt content of a paving mixture

Effective Asphalt Content (Effective Asphalt Content (PPbebe)) is the total asphalt content of a paving

Mixture the portion of asphalt absorbed into the aggregate particles

Absorbed Asphalt Content (Absorbed Asphalt Content (PPbaba)) is the portion of asphalt absorbed intothe aggregate particles

Air voids (Air voids (VVaa)) is the total volume of the small pockets of air between

the coated aggregate particles throughout a compacted paving mixture,expressed as percentage of the total volume of the compacted pavingmixture.

Voids in the mineral aggregate (VMA)Voids in the mineral aggregate (VMA) is the volume of inter granularvoid space between the aggregate particles of a compacted pavingmixture that includes the air voids and the effective asphalt content,expressed as a percentage of the total volume of the compacted pavingmixture.

VoidsVoids fifi lledlled with asphalt (VFA)with asphalt (VFA) is the percentage portion of thevolume of inter granular void space between the aggregate particlesthat is occupied by the effective asphalt. It is expressed as the ratio of(VMA-Va) to VMA

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Dry

A

S.S.D

BMerging

Fully.S.DC

CBA

BulkGSp =.

CBB

EffectiveGSp =.

CA

A

Apparent

GSp

=.

ABAWater =Absorption