accelerated pavementaccelerated pavement testing · definition of apt ¾alt ~ accelerated load...
TRANSCRIPT
ACCELERATED PAVEMENTACCELERATED PAVEMENT TESTING
ISAP International WorkshopCOLD AND WARM ASPHALT MIXTURE DESIGN/ CHARACTERIZATION AND PAVEMENT DESIGNCHARACTERIZATION AND PAVEMENT DESIGN
FortalezaOctober 5-6, 2009
Dr. Angel MateosCEDEX Transport Research Center
Definition of APT
ALT ~ Accelerated Load Testing (of pavements)APT ~ Accelerated Pavement Testing
C t ll d li ti f t t h l l di t b thControlled application of a prototype wheel loading, at or above the appropriate legal load limit to a prototype or actual, layered, structural pavement system to determine pavement response and performanceunder a controlled, accelerated, accumulation of damage in a compressed time period.
(NCHRP Synthesis 235, 1996)( y , )
Controlled application of wheel loading to pavement structures for the purpose of simulating the effects of long-term in-service loadingpurpose of simulating the effects of long-term in-service loading conditions in a compressed time period.
(NCHRP Synthesis 325, 2004)
Types of Facilities
From laboratory devices......but there are also mobile
to Road Tests...to Road TestsFrom linear Test Tracks......to circular Test Tracks
Most of them are fixed...
Traffic Simulation
Hydraulic ActuatorLINTRACK (N th l d )
Pulse LoadingBASt (G ) LINTRACK (Netherlands)BASt (Germany)
Dead WeightCEDEX (Spain)
Real TrucksWesTrack (USA)
European APT Facilities
PTF (Great Britain)HVS-Nordic (Sweden)LIRA (Romania)Mobile Load Simulator
EMPA-ETH (Switzerland) & BASt (Germany)ETH (Switzerland)LAVOC (Switzerland)PTF (Great Britain)University of Nottingham
HVS-Nordic (Sweden)
PTF (Great Britain)RTM (Denmark)
LINTRACK (Netherlands)( )
BASt (Germany)LAVOC (Switzerland)LCPC (France)
CEDEX (Spain)
European APT Facilities
12
10
8
mbe
r Pulse LoadingLinear Test Track
4
6
Num
Linear Test TrackCircular Test Track
2
01965 1970 1975 1980 1985 1990 1995 2000 2005 2009
Year
Introduction to APTActive APT Programs
in the World (2009)
38 Consolidated Programs5 New Programs
Why APT for WMA ?
Rapid evaluation of pavement performanceth i t d f- months instead of years -
P ti l t tPractical output(loads per month)
most facilities...[100 000 – 400 000]
0 0.5 1 1.5 mill.* *
No risk from failure of in-service pavementsNo risk from failure of in-service pavements
“Almost” real materials in “almost” real pavementsost ea ate a s a ost ea pa e e ts
Why APT for WMA ?
Improved understanding of WMA performance
• Monitored structural response• Monitored structural response
• Systematic evaluation of pavement performanceComputer Simulation /Engineering Judgement
Long Term PavementPerformance Studies
• Detailed knowledge of traffic & environmental conditions FI
T
MH
IGH
Engineering Judgement
Ability to control load & environmental variablesBE
NE
F
ME
DIU
M
Field Testing
Ability to control load & environmental variables
• Load related
LOW
Laboratory Testing
Accelerated PavementTesting
Load related...
• Environment related...COST
LOW MEDIUM HIGH
Potential ApplicationsImplementation in M-E designs methods
• because has to be focused on distress mechanisms• because distresses from in-service pavements...
- are difficult to evaluate- are difficult to evaluate- interact to each other- depends on many input random variables
• because models calibration require structural response inputsbecause models calibration require structural response inputs
Comparative testing• because different WMA production technologies exist• does WMA improve HMA performance?• because different WMA production technologies exist
Climatic considerations• because WMA suitability could depend on climatic conditions• because experiences from 1 site could be extrapolated
• because lab. fundamental tests can be related to short-medium term
Laboratory testing protocol
pavement performance• because a WMA design methodology has to be developed
3rd Intl. Conf. on APT
d / t2008www.cedex.es/apt2008
WMA research referenced at...
- MnROAD mainline 5 sections built in 2008- MnROAD mainline, 5 sections, built in 2008
- University of California (UCPRC), 4 sections, tested in 2007-08
Sargand et al. “Testing of Perpetual Pavement with Warm Asphalt Concrete Surface Mixes in the Ohio APLF”
2 4 ti t t d i 20062x4 sections, tested in 2006
Conclusions
APT can pave the gap from WMA Lab. testing to field performance in in-service pavementsp p
An important APT network exists throughout the world
Th d t i i APT b t tThere are many advantages in using APT, but two strengths must be remarked for WMA:
Improved understanding of WMA performance− Improved understanding of WMA performance− Ability to control load & environmental variables
There are some interesting applications:There are some interesting applications:− Implementation in M-E designs methods− Comparative testingg− Climatic considerations− Laboratory testing protocol
Still l t f ill b iStill, long-term performance will be an issue....
ACCELERATED PAVEMENTACCELERATED PAVEMENT TESTING
ISAP International WorkshopCOLD AND WARM ASPHALT MIXTURE DESIGN/ CHARACTERIZATION AND PAVEMENT DESIGNCHARACTERIZATION AND PAVEMENT DESIGN
FortalezaOctober 5-6, 2009
Dr. Angel MateosCEDEX Transport Research Center
Feasibilities of APT Testing- Monitored Structural Response -
δ Temp.
εMBεVεH
σsuction σV
moistureσH
water table level
Feasibilities of APT Testing- Evaluation of Pavement Performance -
10
11
7
8
9
ties
5
6
7
r of F
acili
t
3
4
5
Num
be
1
2
0BearingCapacity
PermanentDeformation
SurfaceCracking
LongitudinalUnevenness
Texture SkidResistance
SensorsResponse
Source:Survey from 11 Full-Scale European Facilities
Feasibilities of APT Testing- Load-related Variables -
L d l lLoad level
Wheel type (single or dual)
................................... ok
........ ok ...but not d
Tire type
Tire inflation pressure
..................................... ok
k
random distribution
Tire inflation pressure
Transverse position
................. ok
................... ok
Axle type ..................................... ?
Feasibilities of APT Testing- Load-related Variables -
140
120APT Traffic Real Traffic
80
100
d (k
N)
60
xle
Load
20
40
Ax
0
20
11
time
Feasibilities of APT Testing- Load-related Variables -
CEDEX Test Track
± 360 mm
3940
41
3940
41
500
1290 mm
2831
3437
2831
3437 500
passes
Vehicle 1 Track 1 Track 2 Track 3 Track 4 Track 5 Track 6 Track 7
60 mm 60 mm 60 mm 60 mm 60 mm 60 mm
Vehicle 2 Track 1 Track 2 Track 3 Track 4 Track 5 Track 6 Track 7
60 mm 60 mm 60 mm 60 mm 60 mm 60 mm
Feasibilities of APT Testing- Load-related Variables -
Axle Type can be Reproduced in Only a Few
p yTest Tracks
LCPC
ALF
Kansas State Univ.
Feasibilities of APT Testing- Load-related Variables -
100
120
100
80
100Range of Realistic Truck Speed
60 6060
80
d (k
m/h
)
4540
40Spee
d
5 6 811 12 12 12 12 13 13 13 13
1620 20 20 20 21 22 22 22 22 24 25 25
20
5 6
01 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Li T t T k Ci l T t T k
Source: 30 Full-Scale Test Tracks around the world
Linear Test Track Circular Test Track
Feasibilities of APT Testing- Environmental Variables -
Air temperature ................................ ® (always)© (some facilities)
Air moisture .......
© (some facilities)
® (when necessary)
Asphalt temperature ........................® (always)© (some facilities)@ (some facilities)
Water table .......@ (some facilities)
® (when necessary)© (some facilities)®Soils moisture ...
® ( l )
® (always)@ (some facilities)
Rainfall .............
F th© Controlled
® (always)© (some facilities)
©Freeze-thaw ..... @ Indirect Control® Recorded
© (some facilities)
Feasibilities of APT Testing- Environmental Variables
air temperature can pbe controlled in any
indoor facility
LAVOC
FAA BASt
Feasibilities of APT Testing- Environmental Variables
a test pit allowspwater table control
LCPC
and homogeneous... and homogeneous support throughout
tests
CEDEX
Feasibilities of APT Testing- Environmental Variables
some facilities are housed in special climatic chambersclimatic chambers
RTM
... where most environment variables
can be controlled
LAVOC
Temp. 4.4 / 21.1 / 40.0 °C
Wh l L d 40 0 kN t 8 k /h32 mm wearing coursetotal: 400 mm ACWheel Load: 40.0 kN at 8 km/h
(dual wheel)total: 400 mm AC
Temp. 50 / 55 °C
Wh l L d 40 60 kN t 12 k /h120 mm WMA (DGAC)
Wheel Load: 40-60 kN at 12 km/h(dual wheel)