KHRI Webinar - AR Pavement Systems - 22 May 20 - Krishna Prapoorna IITT - Compressed (1) - Sankar V AD, KHRI
KHRI Webinar - AR Pavement Systems - 22 May 20 - Krishna Prapoorna IITT - Compressed (1) - Sankar V AD, KHRI
KHRI Webinar - AR Pavement Systems - 22 May 20 - Krishna Prapoorna IITT - Compressed (1) - Sankar V AD, KHRI
Emphasis on Performance-based
Designs and Sustainability
Dr. B. Krishna Prapoorna, Ph.D., F.IRF
Associate Professor, Department of Civil & Environmental Engineering
Indian Institute of Technology Tirupati
AR Band-Aid Patch,
McDonald in 1966
AR Historical Perspective: Initial Paving Applications
1989
Don Nielsen
AR Historical Perspective: Initial Paving Applications
AR – Gap Graded
AR – Open Graded
½ – 1”ARFC
50 – 75 mm ARAC
PCC
Existing / New AC
AR Benefits
üLess Reflective Cracking
üLess Maintenance / More Durable
üLess Raveling
üGood Rut Resistance
üGood Skid Resistance
üSmooth Ride
üGood in Hot & Cold Climates
üLess Splash & Spray
üBetter Drainage
üLess Noise
üCost Effective
üEngineering Use for Old Tires
AR Practice Design Guide
AR
State-of-the-Art
Articles
AR Materials Characterization
12½ - 50 mm ARFC
½ – 1”ARFC
50 – 75 mm ARAC
PCC
Existing / New AC
Viscosity Tests:
Higher Temperatures
Brookfield Rotational
Absolute & Kinematic
Pene
tratio
n & So
fteni
ng Poin
t Broo
kfiel
d Vis
cosit
y
Log Temperature, oR
AR Mixture Characterization
Permanent Deformation:
Triaxial Shear Strength
Dynamic Modulus
Repeated Load
Static Creep
Fatigue Cracking:
Beam Fatigue
Crack Propagation
Semi-Circular Bending
AR binder Characterization
Performance
Laboratory study
experimental Crumb rubber Gradation AR-Gap mix
Task II
program and characterization characterization
mixtures database
Aggregate Gradation study
AR-Gap
Characterization
mixes
Performance
study
AR-Gap Performance
AR-Gap design
performance indicator
criteria
Performance characterization determination
Task III evaluation of AR-
Gap mix
90
V1R3 1.023 0.061 0.926 recovery
0.037 3.61 5.96 90.43
• R increased with increase in
0.8575
Inclusion
V3R1 of CR increased
1.022 0.056
0.1 kPa
the
0.942immediate
0.024 (ε1) &
2.38delayed
5.48(ε2) elastic
92.14
CR dosage indicative of
1.05
3.2 kPa
V3R2 0.075 0.871 0.066 6.52
strain; & reduced the permanent deformation 7.41) 86.07
1.012
increased (ε
60
recovery
1
3
15
V4R2
V3R2 1.042
V3R3 0.164
V4R1 V4R2 0.827V4R3 0.051
CRMB 60 4.93 15.74 79.32 0.85
R2 = 0.997
0.7 Se/Sy = 0.057
V4R31 0.1954 0.786 0.081 7.639 18.40 73.97
0.8
0
0 1.062
2 3 5 6 7 8
n = 1170
Time, s 0.75
CRMB60 0.094 0.889 0.041 3.96 9.20 86.84
VG 10 VG 30 VG40 V1R1 V1R2 V1R3 V3R1 V3R2 V3R3 V4R1 V4R2 V4R3 CRMB 60
1.024 Binders
0.75 0.8 0.85 0.9 0.95
Observed normalized recovery strain
1 1.05
Veena Venudharan, and Krishna P. Biligiri, Conceptualization of Permanent Deformation Characteristics of Rubber Modified Asphalt Binders: Energy-based
Algorithm and Rheological Modeling, Construction and Building Materials Journal, Elsevier, UK, 126, 388-397
Aggregate Gap Gradation Selection
•Gap gradations
Eight
30
100
30 trial gapbygradations
various country/state agencies
100
100 ARIZONA G1 CALIFORNIA
G2 G3 CAROLINA
G4
Gradation A Gradation B
INDIA Gradation
SWEDENC TEXAS
Arizona Texas
25 G1 G2 G3 G4 G5 G6 G7 G8
80
25
ü Gradation
India A – ArizonaCalifornia 8
7
Arizona
Texas
India
Sweden
California
South Carolina
80
80
ü Gradation
G5 G6B – Texas
South Carolina G7 Sweden
G8
%%% %
6
passing
20
ü Gradation C – G8 (this study)
%passing,
Rut depth, mm
20
passing,
60
voids,
60 60 3
2
15
15
gradation study & selection
Cumulative
percent
1
Air
0
0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000
40
Cumulative
40
40 No. of wheel passes
10
Cumulative
10
27 AR-Gap mixtures:
ØThree gap gradations – Gradations ‘A’, ‘B’, & ‘C’
ØThree CRMBs – CRMB60, AR-Fine & AR-Coarse
ØThree binder contents – OBC (Va = 5±1%), OBC+1 (Va
= 3±1%), & OBC-1 (Va = 7±1%)
5000 4.5
CRMB60 AR-Fine AR-Coarse BC-VG40 Gradation 'A'
4500
Gradation 'B'
Resilient Modulus, MPa
4000 4
2500
2000 3
1500
1000 2.5
500
0 2
A₋₁ B₋₁ C₋₁ A B C A₊₁ B₊₁ C₊₁ -4 -3 -2 -1 0 1 2 3 4
Mix types Reduced frequency, Hz
AR-Coarse
70 7
BC - VG40
Rut depth, mm
60 6
50 5
30
• Though gradation ‘C’ outperformed at low-temperature cracking, gradation ‘A’
3
20 2
• AR-Fine binder exhibited higher performance in all the four performance criteria
A₋₁ B₋₁ C₋₁ A B
Mix types
C A₊₁ B₊₁ C₊₁ A₋₁ B₋₁ C₋₁ A B
Mix types
C A₊₁ B₊₁ C₊₁
Moisture Rutting
Veena Venudharan and Krishna P. Biligiri. Investigation of Cracking Performance of
1.8
Asphalt-Rubber
20000
CRMB60 Gap-Graded
AR-Fine AR-Coarse Mixtures: Statistical OverviewCRMB60
BC-VG40 on Materials’
AR-Fine Interface”,
AR-Coarse BC-VG40
Journal of Testing and Evaluation, American Society for Testing and Materials
1.5
No. of cycles to fatigue failure, Nf
International,
15000 USA, September 2019, 47, 1.2 No. 5, pp. 3336-3354
(https://doi.org/10.1520/JTE20180744)
KIC, MPa. √m
0.9
10000
0.6
5000
0.3
0 0.0
A₋₁ B₋₁ C₋₁ A B C A₊₁ B₊₁ C₊₁ A₋₁ B₋₁ C₋₁ A B C A₊₁ B₊₁ C₊₁
Mix types Mix types
125 115 40
DBM
WMM
WMM
125
GSB (Gr- V)
150
GSB (Gr-III)
150
Subgrade
500
AR-Gap Mixture Demonstration Pavement
Test Sections
June 2017
June 2017
AR-Gap Mixture Demonstration Pavement
Test Sections
AR-Gap MIXTURE DEMONSTRATION
PAVEMENT TEST SECTIONS
AR-Gap Mixture Demonstration Pavement
Test Sections
AR-Gap Mixture Demonstration Pavement
Test Sections
AR-Gap Demonstration Pavement Test Sections
– Performance Monitoring
January 2018
AR-Gap Test Sections – Performance Monitoring
AR-Gap TEST
SECTIONS – Monitoring
November 2019
60-65%
Crumb
Rubber 15- 20 %
Modifying
Fillers
20-25%
Bituminous binder
RAR
Sousa et al (2012)
Vinay H. Nanjegowda*, Francisco Silva, Jorge B. Sousa, George B. Way, and Krishna
Prapoorna Biligiri, “Forensic approach to predict film thickness of Reacted and Activated
Rubber (RARX) modified asphalt mixtures”, Road Materials and Pavement Design, Taylor and
Francis, UK (DOI: 10.1080/14680629.2019.1663754)
Previously Accelerated
established Tf loading
data Development of Arizona facility
modified Tf* equation DOT (ALF) test
Mixture design data section data
Establishment of SAF
data
& SA of materials
Established test sections & their
Job-mix formula Analytical investigation Field validation
Optimum Tf*Field
Observed
Threshold
Observed performance
Tf* using
versusfilm both data
equations
thickness,
Previously Tf*
established Tfe
30
30
%&""
Ø 25!∗" = '()
25
×5666
Film thickness Tf* (µ)
*)*+,-778&-2& × 4
Film thickness, Tf (µ)
20 20
10
Optimum film
10 %&""
Ø !5∗" =
'()*)*+,-./0-12 × 4
×5666 thickness
5
0
0
Tf* = 12µ
Tf* = average film thickness, µm
Veff = volume of effective asphalt cement,
liters
Name of the Mixes
W = weight of aggregate, kg
Name of the Mixes
Tf* Tfe
RARX as dry aggregate RARX as binder
FUTURE EXPECTATIONS
Ø Performance of field pavement systems:
Ø Test sections: all road classes
Ø New and innovative materials
Ø Pothole patching techniques
Ø Perpetual and futuristic systems
Ø Encapsulated AR product
Ø Establishing laboratory & field correlations
Ø Develop field design specifications for construction
Ø Sustainable roadway infrastructure: LID
Ø Financial implications: LCA; LCCA; B/C ratio
Foster collaboration(s) between academia &
industry to create SUSTAINABLE roads
IITT ADVANCED PAVEMENT SYSTEMS
(APS) RESEARCH CLUSTER
https://iitt-apsrc.weebly.com
Fundamental Research
Binder
• Semi-automated Penetrometer
• Ring and Ball Apparatus
• Ductilometer
• Rotational Viscometer
Aggregates
• Los Angeles Abrasion test
apparatus
• Length and thickness gauges
Mixtures
• Asphalt Mixer
• Pan Mixer
• Marshall Compactor
• Multi-speed Marshall
Stabilometer
State-of-the-art Advanced Research
• Dynamic Shear Rheometer
• Performance grade binder
characterization
• Linear amplitude sweep
• Creep & recovery
• Superpave gyratory compactor
• Rolling thin film oven
• Pressure aging vessel
• Core drilling machine
• Universal testing machine
• Indirect tensile test
• Dynamic modulus
• Resilient modulus
Salient features of UTM: • Semi-circular bending
§ 16 channel DAQ • Triaxial
§ Computer programmable • Indirect tensile modulus
§ Ability to test asphalt, low-strength • Creep compliance
cement concrete, soil, unbound granular • Four-point bending
materials, fibres, and plastics • Uniaxial cyclic compression
§ Detachable temperature control unit
Ongoing Research by IITT APSRC
• Vehicle-Pavement interaction studies