Towards a sustainable 100% recycling of reclaimed asphalt in road pavements. Road Construction in a post-fossil fuel Society

Transcription

1 CEDR Transnational Road Research Programme Call 212: Recycling: Road construction in a post-fossil fuel society funded by Denmark, Finland, Germany, Ireland, Netherlands and Norway Towards a sustainable 1% recycling of reclaimed asphalt in road pavements - Material Performance International : Road Construction in a post-fossil fuel Society

2 Introduction WP1: Coordination, Management, Advisory board and Dissemination Raw Material characterisation Blends design WP2: Mix and Blend design Validation of Mix Design of %, 3%, 6%, 1% RA Pavement DURABILITY Mix design WP3: Technology up-scaling at asphalt plant Sustainability assessment methodology Technology Up-scaling guidelines WP5: Sustainability Assessment WP4: Performance Assessment LCA and LCCA Mixes and Binder Characterisation Pavement Design Life calculation High Content RA-Warm asphalts for wearing courses Other sustainability metrics

3 Outline Materials Material Performance Binder Performance Asphalt Performance

4 Outline Materials Material Performance Binder Performance Asphalt performance

5 Materials tested Asphalt Mixes for Wearing Courses German asphalt mixes Italian asphalt mixes Asphalt mix : SMA 8S Asphalt Mix : AC 16 Binder type : Polymer modified bitumen PmB 25/55-55 Binder type : Paving bitumen Bitumen type 5/7 % RA 3% RA 6% RA 6% RA + Additives Aggregate type : Gravel and granite sources % RA 3% RA + Additives 6% RA + Additives 9% RA + Additives Aggregate type : Basaltic and volcanic sources Mixture of rejuvenator + warm mix additives 'Storbit+ STORIMPEX Mixture of rejuvenator + warm mix additives Storbit + STORIMPEX Fillers : Limestone Fillers : Limestone Fibers : Pelletized cellulose fibers

6 Materials tested 1 grading limits for SMA 8S [TL Asphalt 9] 1 Passing [M.-%] 8 2 grading limits for AC 16 [ANAS] Sieve [mm] Retained [M.-%] 9

7 SMA 8S with 3% RA SMA 8S with 6% RA SMA 8S with 6% RA + Additive Grading limits for SMA 8S [TL Asphalt 9] Sieve [mm] Passing [M.-%] SMA 8S with % RA 7 2 Grading limits for AC 16 [ANAS] Sieve [mm] Retained [M.-%] Retained [M.-%] Passing [M.-%] Materials tested

8 1 9 Passing [M.-%] SMA 8S with % RA SMA 8S with 3% RA SMA 8S with 6% RA SMA 8S with 6% RA + Additive Grading limits for SMA 8S [TL Asphalt 9] Sieve [mm] AC 16 with % RA 1 AC 16 with 3% RA + Additive 2 AC 16 with 6% RA with Additive 3 AC 16 with 9% RA with Additive 4 Grading limits for AC 16 [ANAS] Sieve [mm] Retained [M.-%] Retained [M.-%] Passing [M.-%] Materials tested

9 Outline Materials Material Performance Binder Performance Asphalt performance

10 Material performance Binders properties characterisation Rutting resistance Multiple Stress Creep recovery test Fatigue resistance Time Sweep test Thermal cracking resistance Critical temperatures

11 Binder performance Rutting resistance Multiple Stress Creep Recovery (MSCR) tests [AASHTO T ] - improvement of the Superpave specification (poor relation authors between Superpave rutting parameter (G*/senδ) and real rutting in mixtures) - test temperature of 6⁰C - 9 stress levels [kpa]:.1,.2,.4,.8, 1.6, 3.2, 6.4, 12.8 and 25.6 Result: Recoverable and Non-Recoverable Creep Compliance (Jnr [%]) for each stress level

12 Binder performance Rutting resistance Recovery [%] of SMA 8S binders at.1 kpa, 3.2 kpa and 6.4 kpa SMA 8S with % RA 6 SMA 8S with 3% RA SMA 8S with 6% RA 5 Recovery % SMA 8S with 6% RA + Additive KPa 3.2 KPa 6.4 KPa increased percentage of RA leads to an increase of the percentage of recovered strains, meaning that better resistance to rutting will be provided.

13 Binder performance Rutting resistance Recovery [%] of AC 16 binders at.1 kpa, 3.2 kpa and 6.4 kpa AC 16 with % RA 4 AC 16 with 3% RA + Additive AC 16 with 6% RA + Additive AC 16 with 9% RA + Additive Recovery % Kpa 3.2 Kpa 6.4 Kpa increased percentage of RA leads to an increase of the percentage of recovered strains, meaning that better resistance to rutting will be provided.

14 Binder performance Fatigue resistance Time Sweep tests - DSR tests - test temperature of 2⁰C - test frequency of 1 Hz - different strain/stress levels - failure considered as the decrease of 5% of the initial complex modulus (G*) Result: Fatigue curves for each binder

15 Binder performance Fatigue resistance Fatigue laws of SMA 8 S binders 1 SMA 8 S with 6% RA + Additive y = x-.22 R² =.9932 Initial Strain [%] SMA 8S with % RA y = x-.233 R² =.9927 SMA 8S with 3% RA y = 25.96x-.219 R² =.9376 SMA 8S with % RA SMA 8S with 6% RA SMA 8S with 3% RA y = 26.19x-.229 R² =.9835 SMA 8S with 6% RA SMA 8S with 6% RA + Additive 1 1, 1, 1, Failure Cycle Nf increased percentage of RA leads to an decrease of fatigue life

16 Binder performance Fatigue resistance Fatigue laws of AC 16 binders 1 AC 16 with % RA AC 16 with 6% RA + Additive y = 28.56x-.242 R² =.9998 AC 16 with 3% RA + Additive AC 16 with 6% RA + Additive Initial Strain [%] AC 16 with 9% RA + Additive AC 16 with 3% RA + Additive y = 3.955x-.254 R² =.9752 AC 16 with 9% RA with Additive y = x-.247 R² = , AC 16 with % RA y = x-.319 R² =.993 1, 1, Failure Cycle Nf [-] increased percentage of RA seems to increase the fatigue life

17 Outline Materials Material Performance Binder Performance Asphalt performance

18 Material performance Asphalt properties characterisation Stiffness behaviour indirect tensile test, four point bending beam test EN Fatigue resistance indirect tensile test, four point bending beam test EN Rutting resistance wheel tracking test, uniaxial cyclic compression tests EN / EN Moisture damage resistance indirect tensile test EN /12

19 Asphalt performance Stiffness behavior - Four Point Bending Beam tests - Indirect Tensile Tests - specimens produced by roller sector compaction - test temperature: -1 to 3⁰C - test frequency:.1hz to 2Hz Result: stiffness modulus master curves - depending on the reduced frequency (αt) determined by Arrhenius equation

20 Asphalt performance Stiffness behavior - different approaches to determine the reduced frequency with constant and variable shift factor (determination of Emin and Emax based on phase angle) Phase [rad] Phase angle angle [rad] Phase angle [rad] C Log1 E [N/mm²] log1 E [N/mm²] 1 C.2 3. C.1-1 C. 5, 1, 15, 2, 25, Complex modulus E [N/mm²] 3, 35, 4,

21 Asphalt performance 25, 25, Stiffness modulus Ereg [N/mm²] Stiffness modulus E [N/mm²] Stiffness behavior 2, 15, 1, 5, -2. Regression Values , 15, 1, 5, Experimental Values. y =.999x R² = , 1, 15, 2, 25, Stiffness modulus Eexp [N/mm²] 6. log(αt f) [-]

22 Asphalt performance Stiffness behavior Master curve of SMA 8 S and AC 16 asphalt Ts=2⁰C SMA 8 S: stiffness increases with an increasing amount of RA AC 16: almost no difference between temperature related stiffness s 25, 2, SMA 8S with % RA AC 16 with % RA SMA 8S with 3% RA AC 16 with 3% RA + Additive Stiffness modulus E [N/mm²] Stiffness modulus E [N/mm²] 25, SMA 8S with 6% RA SMA 8S with 6% RA + Additive 15, 1, 5, , AC 16 with 6% RA + Additive AC 16 with 9% RA + Additive 15, 1, 5, constant shift factor 2. log(αt f) [-] log(αt f) [-] constant shift factor

23 Asphalt performance Stiffness behavior Master curve of German (SMA 8 S) and Italian (AC 16) asphalt Ts=2⁰C 2, 25, SMA 8S with % RA SMA 8S with % RA SMA 8S with 3% RA SMA 8S with 3% RA SMA 8S with 6% RA Stiffness modulus E [N/mm²] Stiffness modulus E [N/mm²] 25, SMA 8S with 6% RA + Additive 15, 1, 5, , SMA 8S with 6% RA SMA 8S with 6% RA + Additive 15, 1, 5, variable shift factor 2. log(αt f) [-] log(αt f) [-] constant shift factor

24 Asphalt performance Fatigue Performance - Four Point Bending Beam tests - Indirect Tensile Tests - specimens produced by roller sector compaction - test temperature of 2⁰C - test frequency of 1Hz Result: fatigue curves - different fatigue criteria used to define the failure load cycle: moment where the stiffness decrease to its half; moment where a macro crack occurs

25 Asphalt performance Fatigue resistance Load cycles to failure (macro crack) NMacro [-] Fatigue curves for SMA 8 S asphalt mixes increasing amount of reclaimed asphalt leads to a better fatigue performance. 1,, SMA 8S with 3% RA 1, SMA 8S with 6% RA y = x R² =.99 1, y = 8.658x-3.49 R² =.99 SMA 8S with % RA y = x R² =.96 1, SMA SMA SMA SMA 8S 8S 8S 8S with with with with % RA 3% RA 6% RA 6% RA + Additive SMA 8S with 6% RA + Additive y = x R² =.98.1 Initial elastic strain, εel,ini [ ] 1

26 Asphalt performance Fatigue resistance Fatigue curves for AC 16 asphalt mixes increasing amount of reclaimed asphalt leads to a better fatigue performance. Load cycles to failure (macro crack) NMacro [-] 1, AC 16 with 6% RA + Additive y = 1.61x-3.55 R² =.99 1, AC 16 with 3% RA + Additive y = 4.69x R² =.97 1, AC 16 with % RA AC 16 with 9% RA + Additive y = 8.644x R² = AC AC AC AC with with with with y =.1721x R² =.99 % RA 3% RA + Additive 6% RA + Additive 9% RA + Additive.1 Initial elastic strain, εel,ini [ ] 1

27 Asphalt performance Fatigue resistance Fatigue curves for SMA 8 S and AC 16 asphalt mixes Load cycles to failure (macro crack) NMacro [-] 1,, 6% RA 1, 1, 6% RA + Additive 1.1 3% RA 3% RA + Additive % RA % RA 1, 1 SMA 8 S 6% RA + Additive 9% RA + Additive AC 16.1 Initial elastic strain, εel,ini [ ] 1

28 Asphalt performance Rutting resistance - Wheel Tracking tests - test temperature of 6⁰C - test frequency of 26.5 Hz - 2, passes - 3 repetitions for each material Results: Proportional Rut Depth (PRDAIR) and Wheel-Tracking Slope (WTSAIR)

29 Asphalt performance Rutting resistance Wheel Tracking Test for SMA 8 S and AC 16 asphalt mixes Mean RDAIR [mm] SMA 8S with % RA SMA 8S with 3% RA SMA 8S with 6% RA SMA 8S with 6% RA + Additive 5, 1, 15, 2, Mean RDAIR [mm] Number of passes [-] AC 16 with % RA AC 16 with 3% RA + Additive AC 16 with 6% RA + Additive AC 16 with 9% RA + Additive 5, 1, 15, 2, Number of passes [-]

30 Asphalt performance Rutting resistance - Uniaxial Compression Tests - test temperature of 3⁰C, 4⁰C and 5⁰C - test frequency of 1 Hz - different stress levels: minimum.5 MPa maximum.925 MPa (3⁰C).9 MPa (4⁰C).5 MPa (5⁰C) - 3, load cycles for each stress level Results: accumulated plastic strains at a desired load cycle as well as the corresponding initial elastic strain

31 Asphalt performance SMA 8S with % RA SMA 8S with 3% RA -2 SMA 8S with 6% RA SMA 8S with 6% RA + Additive Initial elastic strain, εel,ini [ ]. Initial plastic strain, εpl,ini,n=1 [ ] Initial plastic strain, εpl,ini,n=1 [ ] AC 16 with % RA AC 16 with 3% RA + Additive AC 16 with 6% RA + Additive AC 16 with 9% RA + Additive Initial elastic strain, εel,ini [ ] mixture with 6% RA + Add. is likely clear relation between plastic to develop the deepest rut death what deformation behaviour & amount of RA was also observed in the wheel an increasing amount of RA in tracking test as in the binder combination with the use of additives characterisation leads to a lower risk of rutting

32 Asphalt performance SMA 8S with % RA SMA 8S with 3% RA AC 16 with % RA Rutting prediction -2 SMA 8S with 6% RA SMA 8S with 6% RA + Additive Initial plastic strain, εpl,ini,n=1 [ ] Initial plastic strain, εpl,ini,n=1 [ ] Initial elastic strain, εel,ini [ ]. AC 16 with 3% RA + Additive AC 16 with 6% RA + Additive AC 16 with 9% RA + Additive Initial elastic strain, εel,ini [ ] mixture with 6% RA + Add. is likely clear relation between plastic to develop the deepest rut death what deformation behaviour an amount of RA was also observed in the wheel an increasing amount of RA in tracking test as in the binder combination with the use of additives characterisation. leads to a lower risk of rutting

33 Pavement performance Mechanistic design procedure Design input data: Traffic and climate conditions pavement structure Material parameter

34 Pavement performance Deliverable D4.2

35 Outline Materials Material Performance Deliverable D4.1 Binder Performance Asphalt Performance Pavement Performance Deliverable D4.2

36 CEDR Transnational Road Research Programme Call 212: Recycling: Road construction in a post-fossil fuel society funded by Denmark, Finland, Germany, Ireland, Netherlands and Norway