PI:PI: Erol Tutumluer Erol Tutumluer

RA:RA: Tongyan Pan Tongyan Pan

Testing of OMP Aggregates Testing of OMP Aggregates for Shape Propertiesfor Shape Properties

O’HARE Airport Modernization Research ProjectO’HARE Airport Modernization Research Project

Introduction

Aggregates make up Aggregates make up more than 85% of Portland more than 85% of Portland cement concrete and 90% of asphalt pavementscement concrete and 90% of asphalt pavements of of which coarse aggregate constitute the skeleton and which coarse aggregate constitute the skeleton and occupies by far the highest weight or volumeoccupies by far the highest weight or volume

Coarse aggregate are believed to significantly Coarse aggregate are believed to significantly affect affect strength, stability and deformation propertiesstrength, stability and deformation properties, and , and therefore, field performancestherefore, field performances

This project provides This project provides testing and analysistesting and analysis to to establish establish an improved aggregate selection and an improved aggregate selection and evaluationevaluation for O’Hare airport pavements for O’Hare airport pavements

Shape Properties of An Aggregate Particle

Surface Surface TextureTexture

AngularityAngularity

Shape or FormShape or Form

Key Physical Shape Key Physical Shape PropertiesProperties of an of an

aggregate particleaggregate particle

Roughness or irregularity at a micro level Roughness or irregularity at a micro level in contrast with angularity at a macro levelin contrast with angularity at a macro level

• Surface AreaSurface Area

Introduction (cont’d)

Aggregate shape factors, such as Aggregate shape factors, such as flatness and flatness and elongation, angularity, surface texture and surface elongation, angularity, surface texture and surface areaarea influence pavement behavior and performance influence pavement behavior and performance

Aggregate shape has been related to Aggregate shape has been related to permanent permanent deformation and fatigue/cracking resistancedeformation and fatigue/cracking resistance of the of the pavementpavement

Based on current knowledge & past experience: Based on current knowledge & past experience:

Equi-dimensional preferred over Flat & Elongated (F&E)Equi-dimensional preferred over Flat & Elongated (F&E) Crushed (angular) preferred over rounded Crushed (angular) preferred over rounded Rougher surface textured preferred over smoothRougher surface textured preferred over smooth Larger specific surface area preferred for better Larger specific surface area preferred for better

bonding/binding with Portland cement/asphalt cementbonding/binding with Portland cement/asphalt cement

Research Objectives

Quantify Quantify shape, texture, angularity, and surface areashape, texture, angularity, and surface area properties of the coarse aggregates to be used by OMP in properties of the coarse aggregates to be used by OMP in the various layers of the various layers of new runway, taxiway, and shoulder new runway, taxiway, and shoulder pavementspavements

Provide OMP with an Provide OMP with an aggregate shape property databaseaggregate shape property database to efficiently rank and utilize the sources of aggregate to efficiently rank and utilize the sources of aggregate stockpiles according to shape properties available to themstockpiles according to shape properties available to them

Establish a means to Establish a means to develop improved and adaptable develop improved and adaptable Portland cement concrete and asphalt mixture design Portland cement concrete and asphalt mixture design methods and specificationsmethods and specifications that can accommodate that can accommodate aggregates with a wide range of physical characteristics aggregates with a wide range of physical characteristics and aggregate blending alternativesand aggregate blending alternatives

Project Tasks

Task 1:Task 1:

Collect information on the types, geologic origins, Collect information on the types, geologic origins, and quarry sources of the coarse aggregate and quarry sources of the coarse aggregate designated for use by OMPdesignated for use by OMP

This information is crucial for identifying the This information is crucial for identifying the approved aggregate sources and collecting approved aggregate sources and collecting aggregate bag samples for imaging based shape aggregate bag samples for imaging based shape analysis analysis

Subsequently, the acquisition of aggregate bag Subsequently, the acquisition of aggregate bag samples will be facilitated through OMPsamples will be facilitated through OMP

Project Tasks

Task 2:Task 2:

Test OMP coarse aggregates using the UIAIA Test OMP coarse aggregates using the UIAIA automated procedure to quantify 3-D shape, size, automated procedure to quantify 3-D shape, size, angularity, surface texture and surface area and angularity, surface texture and surface area and define proper imaging based morphological indicesdefine proper imaging based morphological indices

(i) maximum, intermediate, and minimum dimensions; (i) maximum, intermediate, and minimum dimensions;

(ii) flat and elongated (F&E) ratio; (ii) flat and elongated (F&E) ratio;

(iii) volume (and weight knowing its specific gravity); (iii) volume (and weight knowing its specific gravity);

(iv) a computed Angularity Index (AI) to indicate how many crushed (iv) a computed Angularity Index (AI) to indicate how many crushed faces are there or how rounded or angular the particle is; faces are there or how rounded or angular the particle is;

(v) a computed Surface Texture (ST) Index to indicate how smooth (v) a computed Surface Texture (ST) Index to indicate how smooth or rough the aggregate particle surface is; and finally, or rough the aggregate particle surface is; and finally,

(vi) a computed Surface Area (SA)(vi) a computed Surface Area (SA)

Advanced Transportation Research & Engineering Laboratory (ATREL) - University of Illinois:

University of Illinois Aggregate Image Analyzer - UIAIA

Developed with funding from FHWA & IDOTDeveloped with funding from FHWA & IDOT

Used in various State and Federal pooled fund Used in various State and Federal pooled fund studies studies [[TPF-5(023)] for evaluating coarse aggregate for evaluating coarse aggregate & linking aggregate shape to pavement performance& linking aggregate shape to pavement performance

In 2005, selected by the In 2005, selected by the NCHRP 4-30NCHRP 4-30 study as one study as one of the 2 promising aggregate image analysis systemsof the 2 promising aggregate image analysis systems

The only system to use three-orthogonally positioned The only system to use three-orthogonally positioned cameras to capture 3-D shape propertiescameras to capture 3-D shape properties

• Conveyor speed of 3 in./second• Particles placed 10 in. apart• Images captured within 0.1 second in succession

Progressive Scan Progressive Scan Video CameraVideo Camera

University of Illinois Aggregate Image Analyzer - UIAIA

Fiber Optic Motion Sensor

National Instruments

•Labview•IMAQ Vision

Image Acquisition

byVirtual

Instrument (VI)

Image Acquisition by UIAIA

45o

Top

Front Side

Three Orthogonal Views

Capture three orthogonal views of a particle

• Top

• Front

• Side

SIDE VIEW

FRONT VIEW

TOP VIEW TOP VIEW

SIDE VIEW

FRONT VIEW

Main Features

Image Capturing – Image Capturing – 1000 particles in 70 1000 particles in 70 minutesminutes

Image Processing / Analysis –Image Processing / Analysis – 2 to 3 2 to 3 sec./particlesec./particle Volume CalculationVolume Calculation Flat and Elongated RatioFlat and Elongated Ratio Particle Size Particle Size DDistribution (Gradation)istribution (Gradation) AngularityAngularity Surface TextureSurface Texture Surface AreaSurface Area

Perform Volume Calculation

Determine if a given pixel in the XYZ space appears in all Determine if a given pixel in the XYZ space appears in all three orthogonal viewsthree orthogonal views

Count number of such pixels (“cubic pixels”)Count number of such pixels (“cubic pixels”) Estimate “cubic pixel or voxel” volumeEstimate “cubic pixel or voxel” volume Convert to volume units Convert to volume units through calibrationthrough calibration x

yz

Ym

ax

Xmax

Zmax

Coarse Aggregate Shape and Size Indices from Imaging

Using UIAIA, developed imaging based shape indices to quantify size and the three key physical shape properties of a coarse aggregate particle

Flat and Elongated (F&E) Ratio Gradation Angularity Index (AI) Surface Texture (ST) Index Surface Area (SA)Surface Area (SA)

Imaging Based Flat & Elongated (F&E) Ratio

Shortest dimension,Shortest dimension,Perpendicular to Perpendicular to

the Longest the Longest DimensionDimension

Longest DimensionLongest Dimension

Plane of Plane of LongestLongest andand Shortest Shortest DimensionsDimensions

F&E RatioF&E Ratio = = Longest dimension / Shortest dimensionLongest dimension / Shortest dimension

All 3 views are analyzed for the longest and shortest dimensionsAll 3 views are analyzed for the longest and shortest dimensions

F&E Ratio Repeatability – Limestone Sample 62A

F & E Ratio CategoryTestMethod

UIAIA trial 3

UIAIA trial 2

UIAIA trial 1

Manual UI

Manual IDOT

WipShape

GA Tech

> 5:1

2.4

2.9

2.4

4.3

2.5

2.1

0.3

> 3:1 & < 5:1

35.5

34.9

34.2

39.0

36.1

31.4

27.5

< 3:1

62.1

62.2

63.4

56.7

61.5

66.5

72.2

Sieve Analysis

Concept — “If two orthogonal Concept — “If two orthogonal dimensions of a particle are greater dimensions of a particle are greater than a given sieve, then the particle is than a given sieve, then the particle is retained on it”retained on it”

The The intermediate dimensionintermediate dimension controls controls the sieve size on which the particle is the sieve size on which the particle is retainedretained square

opening

Di

Di = intermediate

dimension < diagonal opening

Gradation Repeatability – Limestone Sample 67

0

10

20

30

40

50

60

70

80

90

100

1.00 10.00 100.00

Sieve Sizes (mm)

Per

cent

Pas

sing

Blacksburg 67 Trial_1 Blacksburg 67 Trial_2Blacksburg 67 Manual

0.0750.150.30.61.182.364.759.512.519.025.0

Imaging Based Angularity Index (AI)

Extract coordinates of Extract coordinates of the outlinethe outline

Approximate the particle Approximate the particle to a n-sided polygonto a n-sided polygon

Compute angle at Compute angle at vertices,vertices, 11,,22,..,..nn

Determine change in Determine change in angle at each vertex,angle at each vertex, 11,,22,..,..nn

Obtain frequency Obtain frequency distribution ofdistribution of 11,,22,..,..nn

n = no. of sampling points = n = no. of sampling points = 2424Angle at Vertex ‘1’= Angle at Vertex ‘1’= 11 ….. …..

Angle at Vertex ‘n’= Angle at Vertex ‘n’= nn

11--22 = =

11--22 = =

………………....

nn--11 = = nn

n = 1n = 1

22

33

n=24n=24

44

11

22

33

nn

n-1n-1

Angularity Index = AI = Angularity Index = AI = AA11*Area1 + A*Area1 + A22*Area2 + A*Area2 + A33*Area3*Area3

(Area1 + Area2 + Area3)(Area1 + Area2 + Area3)

TheoreticallyTheoretically, A = 0 , A = 0 for a circlefor a circle

For,For,

e = 0, 10, 20, 30….170 for e = 0, 10, 20, 30….170 for Class Interval Class Interval 0-10, 10-20, 0-10, 10-20, 20-30….170-18020-30….170-180

Angularity, A = Angularity, A = e*P(e) / e*P(e) / nn

e=0e=0

e=170e=170

Frequency Distribution Frequency Distribution of of -values -values

0-100-10

170-

180

170-

180

10-2

010

-20

Class IntervalClass Interval

Fre

quen

cyF

requ

ency

Imaging Based Angularity Index (AI)

AI for Gravel, Crushed Stone, & Blend

00

1010

2020

3030

4040

5050

60600-

750-

75

75-1

50

75-1

5015

0-22

5

150-

225

225-

300

225-

300

300-

375

300-

375

375-

450

375-

450

450-

525

450-

525

525-

600

525-

600

600-

675

600-

675

Mor

e

Mor

e th

an 75

0

than

750

AI with AI with nn=24=24

Per

cen

tage

par

ticl

es b

y w

eigh

tP

erce

nta

ge p

arti

cles

by

wei

ght

Crushed StoneCrushed Stone

GravelGravel

BlendBlend

Imaging Based Surface Texture (ST) Index

ErosionErosion DilationDilation

Area AArea A11 Area AArea A22

Image Processing Technique: Image Processing Technique: Erosion and DilationErosion and Dilation

Erosion cycles followed by the same number Erosion cycles followed by the same number of dilation cycles of dilation cycles changechange the original image the original image

The The rougher the particle, the less close the rougher the particle, the less close the rebuilt image is to the originalrebuilt image is to the original

Imaging Based Surface Texture (ST) Index

100*A1

ST A1 A2

STSTparticleparticle AreaArea(fro(front)nt) AreaArea(t(top)op) AreaArea(si(side)de)

STST(front)(front) STST(top(top)) STST(side)(side)AreaArea(front)(front) AreaArea(top)(top) AreaArea(side(side))×× ××××

A1 = Area (in pixels) of the 2-D projection of the particle in the imageA2 = Area (in pixels) of the particle after performing a sequence of “n” cycles of erosion followed by “n” cycles of dilation

AA11AA22BeforeBefore AfterAfter

Samples Used In ST Index Development & Calibration

Rough Crushed StoneRough Crushed Stone Smooth GravelSmooth Gravel

Approximately Approximately 100100 particles each particles each

Limestone

ST for Gravel vs Limestone

Su

rfa

ce T

extu

re In

dex

Su

rfa

ce T

extu

re In

dex

00

11

22

33

44

55

66

00 3030 6060 9090 120120 150150 180180

Max Intercept or Feret Dimension L (pixels)Max Intercept or Feret Dimension L (pixels)

Average ST for Gravel = 0.47Average ST for Gravel = 0.47

Average ST for Limestone = 1.57Average ST for Limestone = 1.57

Typical Ranges of Angularity and Surface Texture Indices

2.202.201.80-2.901.80-2.90550550500-650500-650Crushed GraniteCrushed Granite

1.601.601.20-1.801.20-1.80475475400-550400-550Crushed Crushed

LimestoneLimestone

1.201.201.00-1.501.00-1.50400400300-450300-450Crushed GravelCrushed Gravel

0.900.900.5-1.200.5-1.20300300250-350250-350Uncrushed GravelUncrushed Gravel

MeanMeanRangeRangeMeanMeanRangeRange

Surface Texture (ST) Surface Texture (ST) IndexIndex

Angularity Index (AI)Angularity Index (AI)

Aggregate TypeAggregate Type

Surface Area (SA) Computation

pixe

lpixel

pixe

l

Z

Y

X

O

(0, b, c)

(a, b, 0)

(a, 0, c)

b

c

a

dxdydzdV

(a, b, c)

dxdydzdAParticle Surface

Particle Domain

Summation of the 2-D ∆Si’ contained in voxels forming the particle surface gives the surface area of the particle in units of voxels (pixel cuboids)

Surface Area (SA) Computation

(a) (b)

Central Voxel to be judged

In the smallest containing rectangular box,

Searching for the voxels:

1) Belonging to agg. Particle

•Intensity of three

projection pixels

2) On particle surface

•Six surrounding voxels

Project Tasks

Task 3:Task 3:

Establish a Establish a shape property databaseshape property database for the OMP for the OMP approved aggregate sources for use in pavement approved aggregate sources for use in pavement construction and provide recommendations construction and provide recommendations regarding preferred sourceregarding preferred source

Property variations reported by the various Property variations reported by the various UIAIA imaging based indices will be linked to UIAIA imaging based indices will be linked to laboratory and field performances of Portland laboratory and field performances of Portland cement concrete and asphalt layerscement concrete and asphalt layers for for establishing possible correlationsestablishing possible correlations

Performances of Aggregate Materials in Pavement Structural Layers

Unbound Aggregate Base Resilient ResponseUnbound Aggregate Base Resilient Response

y = 152281e0.001x

R2 = 0.86

175000

200000

225000

250000

275000

200 300 400 500 600

Composite AI Index

Res

ilien

t Mo

du

lus

MR (k

Pa)

Crushed granite-uncrushed gravel blendsCrushed limestone-uncrushed gravel blendsCrushed gravel-uncrushed gravel blendsSlag-uncrushed gravel blendsSandstone-uncrushed gravel blendsUncrushed gravel only

y = 166430e0.1848x

R2 = 0.91

175000

200000

225000

250000

275000

0.50 1.00 1.50 2.00 2.50 3.00

Composite ST Index

Res

ilien

t Mo

du

lus

MR (k

Pa)

Crushed granite-uncrushed gravel blendsCrushed limestone-uncrushed gravel blendsCrushed gravel-uncrushed gravel blendsSlag-uncrushed gravel blendsSandstone-uncrushed gravel blendsUncrushed gravel only

MaterialMaterial Mean AIMean AI (deg)(deg)

Crushed Crushed StoneStone

436436 46.246.2 15.915.9

GravelGravel 322322 40.740.7 12.712.7

BlendBlend 200200 41.441.4 17.217.2

C (psi) C (psi)

Shear PropertiesShear Properties

00 100100 200200 300300 400400 500500

Angularity IndexAngularity Index

(

degr

ees)

(deg

rees

)

40404141424243434444454546464747

RuttingRutting is an aggregate is an aggregate performance indicatorperformance indicatorcontrolled by shear strengthcontrolled by shear strength

Crushed Crushed StoneStone

GravelGravel

50-50 Blend50-50 Blend

Performances of Aggregate Materials in Pavement Structural Layers

Performances of Aggregate Materials in Pavement Structural Layers

Asphalt Concrete Mix Rutting Performances – Asphalt Concrete Mix Rutting Performances – NCAT Test TrackNCAT Test Track

y = -0.0203x + 10.541R2 = 0.80

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

350 370 390 410 430 450 470 490

AI Index

Rut

Dep

th (m

m)

y = -3.632x + 6.9924

R2 = 0.94

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

1.00 1.20 1.40 1.60 1.80 2.00

ST Index R

ut D

epth

(m

m)

y = 563.6x + 0.695R2 = 0.75

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

0.0 0.1 0.2 0.3 0.4 0.5

F & E Ratio Index > 5:1 (percent by weight)

Ru

t D

epth

(m

m)

Performances of Aggregate Materials in Pavement Structural LayersResilient Response of Asphalt Mix SpecimensResilient Response of Asphalt Mix Specimens

y = 628.95ey = 628.95e 0.0027x0.0027x

RR 22 = 0.0141= 0.0141

y = 213.32ey = 213.32e 0.0052x0.0052x

RR22 = 0.7408= 0.7408

00

500500

10001000

15001500

20002000

25002500

30003000

35003500

40004000

45004500

50005000

350350 450450 550550 650650

Composite AIComposite AI

Res

ilien

t M

od

ulu

s (M

Pa)

Res

ilien

t M

od

ulu

s (M

Pa)

Gradation TRZGradation TRZ

Gradation BRZGradation BRZFit (Gradation TRZ)Fit (Gradation TRZ)

Fit (Gradation BRZFit (Gradation BRZ))

y = 3589.1ey = 3589.1e -0.3441x-0.3441x

RR22 = 0.0234= 0.0234

y = 910.84ey = 910.84e 0.5731x0.5731x

RR22 = 0.6009= 0.6009

00

500500

10001000

15001500

20002000

25002500

30003000

35003500

40004000

45004500

50005000

1.001.00 1.501.50 2.002.00 2.502.50 3.003.00

Composite ST IndexComposite ST Index

Res

ilien

t M

od

ulu

s (M

Pa)

Res

ilien

t M

od

ulu

s (M

Pa)

Gradation TRZGradation TRZGradation BRZGradation BRZ

Fit (Gradation TRZ)Fit (Gradation TRZ)Fit (Gradation BRZFit (Gradation BRZ))

Performances of Aggregate Materials in Pavement Structural Layers

Early Age Cracking of Portland Cement ConcreteEarly Age Cracking of Portland Cement Concrete

y = 3E+06x-1.3509

R2 = 0.74

0

50

100

150

200

250

1000 1500 2000 2500

Surface Area Density (m2/m3)

Fra

ctu

re E

ne

rgy

, GF

(N

/m)

12-hour

Fracture Energy

Project Tasks

Task 4:Task 4:

Evaluate Evaluate impact of aggregate shape properties impact of aggregate shape properties on the performanceson the performances of constructed pavement of constructed pavement layers by utilizing the image analyzed coarse layers by utilizing the image analyzed coarse aggregate with cataloged shape propertiesaggregate with cataloged shape properties

Such evaluations will require establishing Such evaluations will require establishing cracking and rutting performance records of the cracking and rutting performance records of the pavement layers to investigate possible pavement layers to investigate possible linkages linkages between imaging based coarse aggregate shape between imaging based coarse aggregate shape indices and the pavement performancesindices and the pavement performances

Project Deliverables

Technical NotesTechnical Notes will be prepared and submitted to will be prepared and submitted to the OMP throughout the duration of this project to the OMP throughout the duration of this project to communicate specific findings and recommendations communicate specific findings and recommendations to OMP engineers as needed to OMP engineers as needed

A A Technical ReportTechnical Report will be prepared at the end of the will be prepared at the end of the laboratory study to document results and findings of laboratory study to document results and findings of the experimental workthe experimental work

The The Project TasksProject Tasks will be pursued in the listed order, will be pursued in the listed order, and the specific delivery of results will be contingent and the specific delivery of results will be contingent upon availability of OMP aggregate samples and other upon availability of OMP aggregate samples and other factors that depend on coordination with OMPfactors that depend on coordination with OMP

Significance of the Project

Provide OMP with Provide OMP with improved aggregate selection criteriaimproved aggregate selection criteria optimized aggregate resource utilizationoptimized aggregate resource utilization construction cost reductionsconstruction cost reductions

Identification and quantification of the influence of Identification and quantification of the influence of aggregate properties on end-use performance to aggregate properties on end-use performance to identify aggregate issues & optimize performanceidentify aggregate issues & optimize performance linked to acceptable limits of aggregatelinked to acceptable limits of aggregate

• shapeshape• angularityangularity• texturetexture

• surface areasurface area