SAT WORKSHOP Performance Grading …...2013/11/04 · SAT WORKSHOP Performance Grading...
Transcript of SAT WORKSHOP Performance Grading …...2013/11/04 · SAT WORKSHOP Performance Grading...
SAT WORKSHOP
Performance Grading Specifications
for Bituminous Binders
Development of PG Binder Specs
Kim Jenkins
tellenbosch
SAT Workshop
March 2016
• Binder blind � unmodified
� PMBs
� non-homogenous (bitumen rubber)
• Binder “fitness for purpose” in asphalt and seals
• Limit new equipment (DSR & ?)
• Address all stages & conditions of usage:� Spraying, mixing and compaction
� High temperature (permanent deformation)
� Intermediate temperature (fatigue)
� Low temperature (cracking)…if necessary
tellenbosch
Traffic Climate Durability
Primary Objectives
Fit for purpose?
Performance Grading
RV +(QC)
DSRBBR
RuttingFatigue CrackingThermal Cracking Production
- 20 0C 20 0C 60 0C 135 0CPavement Temperature
+
PG Systemcombine?
DSR Configurations8 mm diameter
2 mm
Setup for 8 mm parallel plate geometry(for frequency sweep test only)
Bitumen sample
Upper plate(rotating)
Bottom plate(fixed)
8 mm diameter
2 mm
Setup for 8 mm parallel plate geometry(for frequency sweep test only)
Bitumen sample
Upper plate(rotating)
Bottom plate(fixed)
8 mm diameter
2 mm
Gap: 0.063 mm
Setup for 8 mm cone & plate geometry(for creep-recovery test only)
Bitumen sample
Upper plate(rotating)
Bottom plate(fixed)
8 mm diameter
2 mm
Gap: 0.063 mm
Setup for 8 mm cone & plate geometry(for creep-recovery test only)
Bitumen sample
Upper plate(rotating)
Bottom plate(fixed)
Cup & Bob, CC Parallel Plate Cone & Plate
• C&B (CC) suited to viscosity η analysis
• // P variable shear stress across radius, but applicable to most situations
• C&P only necessary for strain sensitive materials
• Max 2 decades of Fr: to remain within strain tolerance?
• IT+LT damage : range of G*=100kPa-1000MPa?
CA
PS
A 2
015
Property
Proposed Classification
58S 64S 58H 64H 58V 64V 58E 64E
-22 -16 -22 -16 -22 -16 -22 -16
Maximum pavement design temperature, Tmax (˚C) 58 64 58 64 58 64 58 64
Minimum grading temperature, Tmin (˚C) -22 -16 -22 -16 -22 -16 -22 -16
Original binder
G*/sinδ, 10rads/sec at Tmax, minimum (kPa) 1.0 1.0 N/A
G*, δ, @ 0.05 to 20 rads/sec, at ([(Tmax-Tmin)/2]+4) °C Report
Viscosity (Pa.s), 135°C, maximum 3.0
Flash Point (˚C), minimum 230
Storage stability, Max % diff, G*T and G*B @Thigh 10
RTFO binder
Maximum Mass Change (m/m %) 1.0
Jnr (ASTM D7405) @ Thigh, maximum 4.5 4.5 2.0 2.0 1.0 1.0 0.5 0.5
G*, δ, @ 0.05 to 20 rads/sec, at ([(Tmax-Tmin)/2]+4)oC Report
Ageing Ratio, G*RTFOT/G*Original, maximum
(10rads/sec)3.0
PAV binder
S(60s) at Tmin + 10oC , MPa, maximum 300
m(60s) at Tmin + 10oC, minimum 0.300
∆Tc(0C), minimum -5
G*, δ, @ 0.05 to 20 rads/sec, at ([(Tmax-Tmin)/2]+4)oC Report
Ageing Ratio, G*PAV/G*Original, maximum
(10rads/sec)6.0
PG Specification Framework
High Temperature 97.5th Percentile 7 day average max.
(CSIR)
64 58
Low Temperature LT Cracking with DSR– Currently SA binder meets -16C (some -22C)
specification
(CSIR)
-7
Outcomes of Franschoek Meeting 1Production & Construction
Industry C&B or RV @ 135 oC Spec ηmax = 3Pa.sEN13702 and Anton Paar Method
Research – Currentlyunderway
Calibration RV vs C&B (JvH)
Spray, Pump, Mix, Pave
Pho
to: K
Lou
w
Effects of Visco -Elasticity inDamage Zone
Elastic
BeforeLoad
DuringLoad
AfterLoad
TyreLoad Recoverable
Deformation
Viscous
BeforeLoad
DuringLoad
AfterLoad
TyreLoad Non-Recoverable
Deformation
Permanent Deformation: Creep and Recovery (MSCR)
AASHTO TP70
Ave permanent shear strain (non-recov) per cycleApplied shear stressJnr =
Findings of PG Spec Research
D’Angelo et al
3.2kPa
Repeatability
ie Spec issues
Outcomes of Franschoek Meeting 2Permanent Deformation DCR
Industry Protocol // Plate @ τ = 0.1 & 3.2 kPa for 10cycles each (measure last 5)CSIR and AASHTO T350 methods
Trial Implementation // Plate @ τ = 0.1 & 3.2 kPa measure 10and 20 cycles
Comments For standard traffic levels, G*/sinδ should suffice, for unmodified binders P
hoto
: G v
Zyl
Dynamic Creep Recovery
Creating a Master Curve
(Rowe, 2015)
Master Curve Example unaged
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.E+07
1.E+08
1.E+09
1.E-05 1.E-04 1.E-03 1.E-02 1.E-01 1.E+00 1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06
|G*|
(P
a)
fr (hz)
80/100 50C 80/100 25C 80/100 10C 80/100 0C CRM 50C CRM 25C CRM 10C CRM 0C
Bredenhann (2015)
Master Curve Example aged
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.E+07
1.E+08
1.E+09
1.E-05 1.E-04 1.E-03 1.E-02 1.E-01 1.E+00 1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06
|G*|
(P
a)
fr (hz)
80/100 50C 80/100 25C 80/100 10C 80/100 0C CRM 50C CRM 25C CRM 10C CRM 0C
Bredenhann (2015)
Black Diagram unaged
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.E+07
1.E+08
1.E+09
1.E+10
0 10 20 30 40 50 60 70 80 90 100
|G*|
(kP
a)
δ (°)
80/100 50C 80/100 25C 80/100 10C 80/100 0CCRM 50C CRM 25C CRM 10C CRM 0CG-R 150 kPa G-R 450 kPa
Bredenhann (2015)
Black Diagram aged
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.E+07
1.E+08
1.E+09
0 10 20 30 40 50 60 70 80 90 100
|G*|
(kP
a)
δ (°)
80-100 50C 80-100 25C 80-100 10C 80-100 0CCRM 50C CRM 25C CRM 10C CRM 0CG-R 150 kPa G-R 450 kPa
Bredenhann (2015)
Master Curve
(Rowe, 2015)
ReferenceTemperature
Master Curve from different tests
(Rowe, 2015)
deflection
Master Curve from different tests
(Rowe, 2015)
deflection
Durability Cracking
• Testing at IT and LT
• Parameters Consider R, ∆Tc , G-R parameter,
etc
deflection
Load
DSR (4mm) BBR
Notes for Durability Tests
DSR for s,m: COV=40%, more expensive, less bit, BR?
BBR for s,m: COV=4%, cheaper, more binder, non-homog
Note
Tmin = -160C is a durability check
NOT at test at -160C !!
23
Log CreepStiffness, S
Log Loading Time
slope = m-value
60 sec8 15 30 120 240
S(60)m(60)
Results of Bending Beam Rheometer
Thermal
Stress build up
Thermal
Stress relaxation
∆TC = TS - Tm = measure of loss in relaxation properties,
taking account of binder ageing
• ∆Tc – shown in both time [top right] domain and temperature domain [bottom right]
• ∆Tc – can be computed from BBR MC analysis
• Same concept can be derived from dynamic data with interrelationship
∆Tc approach
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Which characteristics define
the onset of cracking?
Rate of ageing
Relaxation properties
What causes thermal cracking?
T1
Stress Relaxation α m(60)
Temp
Thermal
Stress or
strain
Fracture stress or
strain
Stress α S(60)
T2
Effective Stresses Small S(60)
high m (60)
are better
Cracking: Glover-Rowe Parameter
G* Test Parameters @ T=150C and Fr = 0.005 rad/sec
Performance Graded Binders for South Africa
Stellenbosch – South Africa , June 13, 2014
www.uwmarc.org
Parameters for IT and LT damage
DSR Parameters: R (Master Curve), G-R parameter (Black Diagram)
(Rowe, 2015)
(Rowe)
G* δ
Durability Cracking
Industry BBR test for S (60) and m (60)∆Tc min = -5 0C
Industry report DSR //P @ Strain sweep G*, δ, @ 0.05 to 20 rads/sec, at ([(Tmax-Tmin)/2]+4)oC
Evaluate R, G-R parameter from DSR data
Pho
to: C
SIR
Stress relaxation properties for IT and LT damage
Property
Proposed Classification
58S 64S 58H 64H 58V 64V 58E 64E
-22 -16 -22 -16 -22 -16 -22 -16
Maximum pavement design temperature, Tmax (˚C) 58 64 58 64 58 64 58 64
Minimum grading temperature, Tmin (˚C) -22 -16 -22 -16 -22 -16 -22 -16
Original binder
G*/sinδ, 10rads/sec at Tmax, minimum 1.0 1.0 N/A
G*, δ, @ 0.05 to 20 rads/sec, at ([(Tmax-Tmin)/2]+4) °C Report
Viscosity Pa.s, 135°C, Pa.s, maximum 3.0
Flash Point (˚C), minimum 230
Storage stability, Max % diff, G*T and G*B @Thigh 10
RTFO binder
Maximum Mass Change (m/m %) 1.0
Jnr (ASTM D7405) @ Thigh, maximum 4.5 4.5 2.0 2.0 1.0 1.0 0.5 0.5
G*, δ, @ 0.05 to 20 rads/sec, at ([(Tmax-Tmin)/2]+4)oC Report
Ageing Ratio, G*RTFOT/G*Original, maximum
(10rads/sec)3.0
PAV binder
S(60s) at Tmin + 10oC , MPa, maximum 300
m(60s) at Tmin + 10oC, minimum 0.300
∆Tc(0C), minimum -5
G*, δ, @ 0.05 to 20 rads/sec, at ([(Tmax-Tmin)/2]+4)oC Report
Ageing Ratio, G*PAV/G*Original, maximum
(10rads/sec)6.0
PG Specification Framework
DSR BBR
Benefits of PG Spec for SA?
• Binder selection based on traffic, climate
• Product innovation reliably assessed eg PMBs
• Permanent deformation reliably evaluated
• Long Term Ageing finally assessed, for thin layers in SA context!!
• Durability – stress relaxation holistically assessed (not fatigue versus LT fracture)
• Resource economy in test apparatus & methods (but bitumen sample size IT and LT!)
• No binder grade proliferation
The future is
so bright, I
need shades.
Thank you!