ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 1 MODELS FOR PERMANENT DEFORMATION FOR BITUMINOUS BOUND MATERIALS IN FLEXIBLE PAVEMENTS Modelling

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 2 OUTLINE Test programme (Vienna-meeting) Specimens from LAVOC Models Modelling Calibration Data from test tracks Further Steps Discussion and Questions

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 3 Test programme WP5 Open file:

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 4 Specimens from LAVOC 45cm 80cm 40mm 2x90mm threads

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 5 Specimens from LAVOC: cutting scheme LCPC (large size) DRI (small size, B in water) ISTU (uniaxial and triaxial testing) SHELL (NAT) TRL (cores, B in air) broken Plate 1Plate 3Plate 2Plate 6Plate 5 1/11/2 1/1 2/12/2 2/1 3/1 3/2 6/1 6/2 5/25/1 Problems: threads in corners lateral surfaces non-planar bonding between layers

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 6 MODELS for validation SPDM Francken (?) Huet - Sayegh Burger Power Law Generalized Maxwell DBN (?) material model rutting prediction model rheological models

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 7 RHEOLOGICAL MODELS G0G0 G1G1 G2G2 GnGn 11 22 nn    Generalized Maxwell model E2E2 E1E1 22 11 Burger model EaEa  a, k a  b, h b EpEp Huet – Sayegh model J0J0 J 1, m Power Law

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 8 MODELLING: Rheological models Stress tensor deviatoric partvolumetric part rheological model FE - code constitutive equations K0K0 Linear elastic model G0G0 G1G1 G2G2 GnGn 11 22 nn    Generalized Maxwell model

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 9 CALIBRATION FE - code lab tests data fitting determination of test parameters wheel tracking test simulationsimulation of loaded structure determination of model parameters

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 10 Determination of Test Parameters from Lab Tests Hydrostatic tests: axial pressure = confining pressure - static - dynamic (sinusoidal load) Deviatoric tests: confining pressure = 0 (uniaxial) - static - dynamic (sinusoidal load) Determination of test parameters: E*, 

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 11 Determination of Model Parameters from Data Fitting Lab tests E* and  for various T and f example: data fitting for Huet-Sayegh model

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 12 example: data fitting for Huet-Sayegh model Model parameters: E a, E p, k a, h b 20°C10°C0°C-10°C Cole-Cole-Diagram for Huet – Sayegh model Determination of Model Parameters from Data Fitting Lab tests E* and  for various T and f

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 13 Data from test tracks missing data Lausanne, ALT at LAVOC Test track Denmark LCPC, Nantes test track, historical data

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 14 MATERIALS: data from Denmark Upper layer AB 11tLower layer ABB 16 Maximum grain size [mm]1116 Type of binderB 70/100B 40/60 Pen at 25°C [10 -1 mm]8550 Ring and Ball [°C]47,051 Binder content [%-m]5,185,1 Air voids content [%]3,04,0 Marshall density [g/cm³]2,9792,449 Maximum density [g/cm³]3,206- Marshall stability [kN]11,009,00 Marshall flow [mm]3,0 Aggregate density [g/cm³]3,6322,72 Bulk density [g/cm³]3,1722,409 Sample standard deviation for 4 specimens [g/cm³] 0,04130,0099 Dynamic viscosity at 60°C(DRI) Dynamic viscosity at 50°C(DRI) Open file:

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 15 FURTHER STEPS Activity of PartnerSchedulePartner laboratory tests at ISTUfrom ISTU-Lab missing data (test tracks)asapDRI, LCPC SHELL model laboratory tests (NAT, viscosity)until SHELL, DRI FE-code implementation and testsuntil ISTU results from wheel tracking tests (TRL, DRI, LCPC) until all WPP data fitting from material testsfrom ISTU simulation of loaded structurefrom ISTU wheel tracking test simulationfrom ISTU validation and report ISTU Deliverable ISTU

Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 16 OPEN QUESTIONS Test track data: list with required data will be sent to LCPC and DRI Material Denmark: sample preparation ? Francken model: determination of test parameters ? DBN: 3D-version not published – time? Viscosity data: which type of test used? SPDM-software: only for modified bitumen

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 17 Thank You for Your attention! P.S.: Where is our MONEY???

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 18 Key equations:  p...plastic deformation  1...amplitude of vertical stress  3...lateral stress E p...plastic deformation modulus N...number of load repetitions f...load frequency f()... coefficient, dependent on the void content E*...complex elastic modulus E ∞...purely elastic or „glassy“ modulus R*...reduced modulus T...temperature V A...aggregate content [Vol %] V B...binder content [Vol %] F*...reduced shear modulus (binder) Francken / Key equations

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 19 Input parameters for the model: Complex elastic modulus E* Complex shear modulus G* of the binder Aggregate content [vol. %] Binder content [vol. %] Francken / Input parameters Triaxial test DSR and vol. asphalt characteristics

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 20 Key equations: S mix,v Stiffness of the mix S bit,v Viscous component of the stiffness of the bituminous binder b, q... Parameters, specific for a certain asphaltic mix, determined by creep tests  0...Bitumen viscosity at the average paving temperature W eq...ESALs t w...Wheel loading time (traffic speed) h...Rut depth k...Coefficient k=C m Z 0, dynamic factor C m = 1 by default Z 0...Configuration factor  0...Contact stress of the standard wheel  av,0...Average stress in the asphalt layer resulting from one standard wheel pass h...Thickness of the asphalt layer SPDM / Key equations

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 21 SPDM / Input parameters Input parameters for the model: Traffic: axle loads, wheels per axle, axles per day and line, contact stress, rate of traffic growth per year, design period, loading time Climate: MMAT (Mean Monthly Air Temperature in °C) Material characteristics: penetration of the bitumen at 25°C, softening point of the bitumen, polymer modified bitumens: viscosities at two temperatures, mix composition (Vol.% bitumen, Vol.% aggregate), creep characteristics (parameters q and b) Structure: total thickness of asphalt layers, thickness of sub- base, Poisson’s ratio of asphalt layers, of the sub-base and of the subgrade, modulus of elasticity of the sub-base and the subgrade

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 22 Uniaxial and Triaxial Tests Creep tests The applied axial load is constant, so that specimen failure does not result from sudden load pulses. Most of these tests are run in compression states of stress. Repeated Load Tests A block pulse waveform that is not symmetric is applied to the specimen. One load cycle contains a load period and a rest period. Cyclic Load Tests Axial symmetric load curves are applied to the test specimen. Tests can be run in tension-compression as well as in compression only.

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 23 Test Types / Uniaxial and Triaxial Tests creep repeated load cyclic load

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 24 MATERIALS: Data from ALT in Lausanne Surface layer AB 11s Upper base layer HMT 22s Lower base layer HMT 22s Layer thickness [mm]4090 Maximum grain size [mm]1122 Type of binderB 50/70 Pen of recovered bitumen [10 -1 mm]3025,029 Ring and Ball [°C] of the recovered bitumen 58,862,259,1 Binder content [%-m]5,63,794,4 Voids content [%-vol]11,17,34,7 Rate of compaction [%]95,398,899,7 Marshall stability [kN]10,09,011,5 Marshall flow [mm]2,73,13,5 Marshall voids content [%-vol]6,46,24,9

ISTU Institute for Road Construction and Maintenance – Vienna University of Technology SAMARIS – Presentation Modelling– WP5 Meeting Wokingham, UK – 02/03/05 25 MATERIALS: ALT in Lausanne/ surface layer Grading: Sieve size [mm] % passing