Findings in WMA Project (SD ) Session C, Technical Session I

Transcription

1 Findings in WMA Project (SD ) Session C, Technical Session I Elie Y. Hajj, Ph.D. Assistant Professor Western Regional Superpave Center Department of Civil and Env. Engineering University of Nevada, Reno South Dakota Asphalt Conference Pierre, SD April 3, 2013

2 Presentation Outline Overall Study Objectives Laboratory Evaluation of Lab-produced Mixtures Field Projects Document construction Evaluation of Field-Produced Mixtures Field Performance Monitoring Future Research Activities 2

3 Overall Research Objectives Evaluate various types of WMA technologies for applications in SD. Assess the performance of WMA test sections. Conduct cost/benefit analysis for WMA. 3

4 Laboratory Evaluation of Lab-produced Mixtures 4

5 Laboratory Evaluation Objective Evaluate the potential performance of WMA additives used with typical SD aggregate sources. Investigate the impact of WMA additives on the overall performance of the mixtures. Assess the possibility of WMA additives to improve the workability of the mixtures on the expense of their performance characteristics. 5

6 Laboratory Evaluation Experimental Plan Materials Aggregates: 3 sources Quartzite, Limestone, & Natural Gravel Asphalt binder: 1 source PG64-28 Hydrated lime: 1% by dry weight of aggregate WMA Technologies Advera: 0.3% by total weight of mixture Evotherm 3G: 0.5% by weight of binder Plant Foaming: 1.5% water by weight of binder 6

7 Laboratory Evaluation Experimental Plan (Full Factorial) Mixture Aggregate source Short-Term Oven Aging Conditions Quartzite Limestone N. Gravel Volumetric Performance HMA X X X 2hrs@Comp. Temp 4hrs@275 F WMA-Advera X X X 2hrs@Comp. Temp 2hrs@Comp. Temp WMA-Evotherm X X X 2hrs@Comp. Temp 2hrs@Comp. Temp WMA-Foaming X X X 2hrs@Comp. Temp 2hrs@Comp. Temp HMA-2hrs STOA X X NT* 2hrs@Comp. Temp 2hrs@275 F HMA-Low Temp X X X 2hrs@WMA Comp. Temp * Not Tested (short on materials) 2hrs@WMA Comp. Temp 7

8 Laboratory Evaluation Mix Designs (According to NCHRP 9-43 guidelines) Study supported Mixing/Compaction NCHRP 9-43 Temperatures findings: ( F) For aggregates with 1.0 % binder absorption, the HMA Aggregate WMA- WMA- WMA- HMA-2hrs HMA-Low HMA Source mix design can be Advera used Evotherm for WMA Foaming mixtures. STOA Temp Quartzite 325/ / / / / /225 The absorptions for Quartzite, Limestone and Natural Gravel aggregates were found to be 0.45, 0.21 and 0.91%, respectively. Limestone 325/ / / / / /235 Natural Gravel 325/ / / / / /240 Aggregate Source Quartzite Limestone Natural Gravel Spec. Binder Content, % Air Voids, %

9 Laboratory Evaluation Mechanical Properties 1. Moisture damage: AASHTO T283 (TSR). 2. Mechanical Property: Dynamic Modulus Master Curve. 3. Rutting: Asphalt Pavement Analyzer (APA) and Flow Number (FN). 4. Thermal Cracking: Thermal Stress Restrained Specimen Test. 5. Fatigue Cracking: Flexural Beam Fatigue. 9

10 Laboratory Evaluation 1. Moisture Damage Follow AASHTO T283 except: 4 replicates per condition Average Wet Tensile Strength Average Dry Tensile Strength TSR = x % Average wet tensile strength Average dry tensile strength 10

11 Tensile Strength ITS at 77 F (25 C), psi Laboratory Evaluation 1. Moisture Damage Quartzite Aggregate HMA WMA-Advera WMA-Evotherm WMA-Foaming HMA-2hrs STA HMA-low Temp Mixture Type Tensile Strength Ratio at 77 F (25 C), % 11 Dry ITS, psi Dry Wet ITS, ITS, psi psi Tensile Strength Ratio (TSR)

12 Tensile Strength ITS at 77 F (25 C), psi Laboratory Evaluation 1. Moisture Damage Limestone Aggregate HMA WMA-Advera WMA-Evotherm WMA-Foaming HMA-2hrs STA HMA-low Temp Mixture Type Tensile Strength Ratio at 77 F (25 C), % 12 Dry ITS, psi Wet ITS, psi Tensile Strength Ratio (TSR)

13 Tensile Strength ITS at 77 F (25 C), psi Laboratory Evaluation 1. Moisture Damage Natural Gravel Aggregate HMA WMA-Advera WMA-Evotherm WMA-Foaming HMA-low Temp Mixture Type Tensile Strength Ratio at 77 F (25 C), % 13 Dry ITS, psi Wet ITS, psi Tensile Strength Ratio (TSR)

14 Laboratory Evaluation 1. Moisture Damage Paired Mean Comparison ( = 0.05) HMA vs. HMA-2hrs STA: the reduction of time for the STA reduced dry & wet TS. HMA vs. HMA-Low Temp mixtures: the reduction of production temperature & time & temperature of STA reduced dry & wet TS. WMA vs. HMA mixtures: WMA had lower dry & wet TS for all aggregate types (Within each aggr. type: WMA had similar dry TS). WMA vs. HMA-2hrs STA mixtures: Similar dry & wet TS. WMA vs. HMA-Low Temp mixtures: Similar dry & wet TS. 14

15 Laboratory Evaluation 1. Moisture Damage Results of ANOVA analysis: Aggregate type, Mix type & their interactions significantly impact the dry & wet TS values of the asphalt mixtures. 100 TSR at 77 F, % Quartzite Limestone Natural Gravel HMA HMA-2hrs STOA WMA w/o Additive WMA-Advera WMA-Evotherm WMA-Foaming 15

16 Laboratory Evaluation 2. Mechanical Property: E* AASHTO TP79 and PP62: E* Temperatures: 14, 40, 70, 100 & 130 F (-10, 4.4, 21.1, 37.8 & 54.4 C) Loading frequencies: 0.1, 0.5, 1, 5, 10, & 25 Hz at each temperature. 16

17 Laboratory Evaluation 2. Mechanical Property: E* Dynamic Modulus E* at 70 F, ksi 1, Quartzite Aggregate 10 1.E-03 1.E-02 1.E-01 1.E+00 1.E+01 1.E+02 Reduced Frequency, Hz HMA Advera Evotherm Foaming HMA-2hrs STA HMA-Low Temp 17

18 Laboratory Evaluation 2. Mechanical Property: E* Dynamic Modulus E* at 70 F, ksi 1, Limestone aggregate 10 1.E-03 1.E-02 1.E-01 1.E+00 1.E+01 1.E+02 Reduced Frequency, Hz HMA Advera Evotherm Foaming HMA-2hrs STA HMA-Low Temp 18

19 Laboratory Evaluation 2. Mechanical Property: E* Dynamic Modulus E* at 70 F, ksi 1, Natural Gravel aggregate 10 1.E-03 1.E-02 1.E-01 1.E+00 1.E+01 1.E+02 Reduced Frequency, Hz HMA Advera Evotherm Foaming HMA-Low Temp 19

20 Laboratory Evaluation 2. Mechanical Property: E* Results of ANOVA analysis: Aggregate type, WMA additive & their interactions significantly affect the E* of the mix. 20

21 Laboratory Evaluation 3. Rutting APA Air voids: 4.5 ± 0.5 percent Test temperature: 147 F (64 C) SDDOT gyratory controlled QC/QA mix design specs for hot asphalt mixtures: Max RD of 7.0 mm 21

22 Laboratory Evaluation 3. Rutting APA Test Results APA Rut Depth at 147 F (64 C), mm Not Tested Quartzite Lime Stone Natural Gravel 22

23 Laboratory Evaluation 3. Rutting: APA Paired Mean Comparison ( = 0.05) HMA vs. HMA-2hrs STA: No impact for reduction of time for STA. HMA vs. HMA-Low Temp: Reduction of production temperature & time & temperature of STA increased RD for Limestone only. WMA vs. HMA: Quartzite & N. Gravel: Similar RD for all mixes except for Foaming (higher RD). Limestone: Similar RD for all WMA mixes & higher than HMA. WMA vs. HMA-2hrs STA: Quartzite: Similar RD for all mixes except for Foaming (higher RD). Limestone: Similar RD for all WMA mixes & higher than HMA-2hrs STA. WMA vs. HMA-Low Temp: Similar RD to all WMA mixes. 23

24 Laboratory Evaluation 3. Rutting FN AASHTO TP79: Flow Number (FN) Air voids: 4.5 ± 0.5 percent Deviator stress = 87 psi Unconfined Test temperature = 136 F (58 C) 24

25 Laboratory Evaluation 3. Rutting FN Flow Number HMA WMA-Advera WMA-Evotherm WMA-Foaming HMA-2hrs STA HMA-low Temp Quartzite Lime Stone Natural Gravel 25

26 Laboratory Evaluation 4. Thermal Cracking Thermal Stress Restrained Specimen Test (TSRST) Cools down the specimen at a rate of 10 C/hour Long-term aged specimens: 5 days at 185 F (85 C) Air voids: 7.0 ± 0.5 percent Thermal Stress (psi) Mix A - Replicate 1 Mix A - Replicate 2 Mix B - Replicate 1 Mix B - Replicate Temperature ( C)

27 Fracture Temperature( C) Laboratory Evaluation 4. Thermal Cracking HMA WMA-Advera WMA-Evotherm WMA-Foaming HMA-Low Temp Mixture Type Quartzite Limestone Natural Gravel 27

28 Laboratory Evaluation 4. Thermal Cracking Quartzite-HMA Limestone-HMA Natural Aggregate-HMA Fracture shows some broken rock, some adhesion failure, and most failure in binder. 28 A lot of fractured aggregate (weak rock) and more adhesion failure. Note: Limestone had low binder absorption. Significant aggregate breaking was seen in weaker fine sandstones. Darker brown rocks were very fine sandstone/siltstone. Some adhesion failure is also present.

29 Laboratory Evaluation 4. Thermal Cracking Aggregate source plays a major role on both fracture stress & fracture temperature. Fracture temperatures of all mixtures made with Quartzite & Limestone aggregates were colder than the low temperature PG of binder (i.e. -28 o C) Fracture temperatures of all mixtures made with the natural gravel aggregate were slightly warmer than the low temperature PG of binder (i.e. -28 o C). 29

30 Laboratory Evaluation 5. Fatigue Cracking Flexural Bending Beam Fatigue Long-term aged specimens: 5 days at 185 F (85 C) Air voids: 7.0 ± 0.5 percent Test temperature: 70 F (21 C) 1,000 Flexural Strain (microns) 100 1,000 10, ,000 1,000,000 Cycles to Failure 30

31 Laboratory Evaluation 5. Fatigue Cracking 1,000 Fatigue relationships at 70 F for Quartzite aggregate Flexural Strain (microns) 100 1,000 10, ,000 1,000,000 Cycles to Failure HMA HMA-2hrs STA HMA-Low Temp WMA-Advera WMA-Evotherm WMA-Foaming 31

32 Laboratory Evaluation 5. Fatigue Cracking 1,000 Fatigue relationships at 70 F for Limestone aggregate Flexural Strain (microns) 100 1,000 10, ,000 1,000,000 Cycles to Failure HMA HMA-2hrs STA HMA-Low Temp WMA-Advera WMA-Evotherm WMA-Foaming 32

33 Overall Summary Statistical Ranking of mixtures Property Aggregate WMA-Advera WMA-Evotherm WMA-Foaming HMA-2hrs STA HMA-Low Temp Compaction/ Aging Temp(F) Quartzite Limestone Nat. Gravel Dry TS Quartzite Limestone Nat. Gravel Wet TS Quartzite Limestone Nat. Gravel E* Values Quartzite Limestone Nat. Gravel APA Rut Depth Quartzite Limestone Nat. Gravel FN Values Quartzite Limestone Nat. Gravel Fracture Temperature Fatigue 33 Charac. Quartzite Limestone Nat. Gravel Quartzite Limestone

34 Overall Summary Ranking of mixtures The impact of the type of WMA additive on the properties of asphalt mixtures highly depends on aggregate type: Quartzite & Limestone: Overall Foaming seems to work best followed by Advera Evotherm may improve APA rut depth. Moisture sensitivity may be of concern. Natural Gravel: All three WMA additives provided similar mixtures properties. 34

35 Overall Summary Ranking of mixtures Although all mixes passed SDDOT TSR of 80% min. Evotherm provided lowest TSR with Quartzite aggregate best TSR with Limestone aggregate Advera provided lowest TSR with Limestone aggregate second lowest with Quartzite aggregate Within each aggregate type; the type of WMA additive did not have a significant impact on fracture temperature. Regardless of aggregate type (Quartzite and Limestone), Evotherm improved mixture fatigue characteristics. 35

36 Field Projects 36

37 Field Projects Date of Construction Project Location Highway 73 Highway 20/79 Highway 18 Highway 262 April 2010 June 2010 October 2011 October 2012 From Hwy 18 N to Bennett-Jackson Co line From Prairie City to 2.6 miles west Bison Southwest of SD from Oglala to Pine Ridge Southeast of SD from Alexandria to Bridgewater Project Length 12.3 miles miles 17.0 miles WMA Technologies Evotherm Evotherm, Foam Advera, Evotherm, Foam Advera, Evotherm, Foam HMA Section Yes Yes Yes Yes Binder Grade PG64-28 PG64-28 PG64-34 SBS PG58-34 Aggregate Type Natural Gravel Natural Gravel Limestone Quartzite RAP No No No Yes 37 4/3/2013

38 Evaluation of Field-Produced Mixtures Overall Progress Core Samples Field- Produced Mixtures Project Name Highway 73 Highway 20/79 Highway 18 Highway 262 Construction Date Apr-10 Jun-10 Oct-11 Oct-12 PG Grading To Be sampled Summer Completed Completed In Progress (Extracted/Recovered AC) 2013 TSR Completed Completed In Progress To Be sampled Summer 2013 APA Completed Completed In Progress To Be sampled Summer 2013 Overlay Tester Completed Completed In Progress To Be sampled Summer 2013 E* Not Sampled Not Sampled Completed In Progress APA Not Sampled Not Sampled Completed In Progress FN Not Sampled Not Sampled Completed In Progress TSR Not Sampled Not Sampled Completed In Progress TSRST Not Sampled Not Sampled In Progress In Progress Overlay Tester Not Sampled Not Sampled Completed In Progress Completed In Progress To Be sampled Summer 2013 Not Sampled Laboratory evaluation of field produced mixtures including E*, APA, FN, TSR, TSRST, and Overlay Tester 38

39 Evaluation of Field-Produced Mixtures TSR Results- Limestone Aggregate (HWY 18) Tensile Strength at 77 F(25 C), psi HMA WMA-Advera WMA-Evotherm WMA-Foaming Mixture Type Dry TS, psi Wet TS, psi Tensile Strength Ratio (TSR) Tensile Strength Ratio at 77 F (25 C), % 39

40 Evaluation of Field-Produced Mixtures APA Results- Limestone Aggregate (HWY 18) Rut Depth (mm) at 147 F (64 C) HMA WMA-Advera WMA-Evotherm WMA-Foaming Mixture Type Allowable Max Rut Depth 40

41 Evaluation of Field-Produced Mixtures E* Results- Limestone Aggregate (HWY 18) Dynamic Modulus, Ksi at 70 F ,463 1,334 1,263 1,304 1,236 1,127 1,065 1,099 1, Frequency, Hz HMA WMA-Advera WMA-Evotherm WMA-Foaming

42 Evaluation of Field-Produced Mixtures FN Results- Limestone Aggregate (HWY 18) Flow Number at 136 F (58 C) HMA WMA-Advera WMA-Evotherm WMA-Foaming Mixture Type 42

43 Evaluation of Field-Produced Mixtures TTI Results- Limestone Aggregate (HWY 18) Number of Cycles to failure at 50 F HMA WMA-Advera WMA-Evotherm WMA-Foaming Initial Load ( lbf ) Mixture Type Number of Cycles Initial Load (lbf) 43

44 Field Performance Monitoring Overall Progress Core Samples Field- Produced Mixtures Project Name Highway 73 Highway 20/79 Highway 18 Highway 262 Construction Date Apr-10 Jun-10 Oct-11 Oct-12 PG Grading To Be sampled Summer Completed Completed In Progress (Extracted/Recovered AC) 2013 TSR Completed Completed In Progress To Be sampled Summer 2013 APA Completed Completed In Progress To Be sampled Summer 2013 Overlay Tester Completed Completed In Progress To Be sampled Summer 2013 E* Not Sampled Not Sampled Completed In Progress APA Not Sampled Not Sampled Completed In Progress FN Not Sampled Not Sampled Completed In Progress TSR Not Sampled Not Sampled Completed In Progress TSRST Not Sampled Not Sampled In Progress In Progress Overlay Tester Not Sampled Not Sampled Completed In Progress Completed In Progress To Be sampled Summer 2013 Not Sampled Laboratory evaluation of core samples including Moisture Damage, Rutting, and PG grading 44

45 Field Performance Monitoring TSR Results-Natural Gravel (HWY 73) Tensile Strength at 77 F (25 C), psi Va=6.0 ±0.04% Va=6.0 ±0.02% Va=6.0 ±0.02% Va=6.0 ±0.01% 69.9 HMA WMA-Evotherm Mixture Type Dry ITS, psi Wet ITS, psi Tensile Strength Ratio (TSR) Tensile Strength Ratio at 77 F(25 C), % 45

46 Field Performance Monitoring TSR Results-Natural Gravel (HWY 20) Tensile Strength at 77 F(25 C), psi Va=5.9 ±0.01% Va=8.3±0.1% Va=6.8±0.02% Va=5.9 ±0.01% Va=6.1±0.05% 54.0 Va=6.9±0.01% HMA WMA-Evotherm WMA-Foaming Mixture Type Dry TS, psi Wet TS, psi Tensile Strength Ratio (TSR) Tensile Strength Ratio at 77 F (25 C), % 46

47 Field Performance Monitoring APA Results-Natural Gravel (HWY 73) Rut Depth (mm) at 147 F (64 C) Va=6.0% Wheel Path HMA 4.72 Va=6.7% Between Wheel Path Mixture Type 4.89 Va=4.6% Wheel Path WMA-Evotherm 3.03 Va=6.5% Between Wheel Path 47

48 Field Performance Monitoring APA Results-Natural Gravel (HWY 20) Rut Depth (mm) at 147 F (64 C) Va=6.0% Va=5.8% Va=8.7% Va=8.4% Va=6.2% Va=6.4% Wheel Path 3.00 Between Wheel Path 4.08 Wheel Path 3.31 Between Wheel Path 3.72 Wheel Path 3.98 Between Wheel Path HMA WMA-Evotherm WMA-Foaming Mixture Type 48

49 Field Performance Monitoring TTI Results-Natural Gravel (HWY 73) Number of Cycles to failure at 50 F Va=5.7±0.02% HMA 1095 Va=6.2±0.01% WMA-Evotherm Mixture Type Initial Load ( lbf ) Number of Cycles Initial Load (lbf) 49

50 Field Performance Monitoring TTI Results-Natural Gravel (HWY 20) Number of Cycles to failure at 50 F Va=5.5±0.01% Va=6.8±0.05% Va=6.0±0.01% HMA WMA-Evotherm Mixture Type WMA-Foaming Number of Cycles Initial Load ( lbf ) 50

51 Future Research Activities Field cores from Highway SR 262. Energy Consumption Comparison between HMA and WMA. Analysis of field data (in-place density, thermo-graphic imaging data, ) 51

52 Thank you! For more information: Elie Y. Hajj: Peter E. Sebaaly: Western Regional Superpave Center: Asphalt Research Consortium: 52