Axial DENT Development & Result. Asphalt Institute Summer Meeting TAC Meeting August 9, 2017 Montreal, QC

Transcription

1 Axial DENT Development & Result Asphalt Institute Summer Meeting TAC Meeting August 9, 207 Montreal, QC

2 Axial DENT Test Procedure Test temperature the 5 C 3 ligaments similar to Ontario procedure, but does not require a ductility bath and also requires less PAV residue Less than 20 gram of PAV residue required Due to difference in specimen gauge length I changed the pull rate from 50 mm/min to 24 mm/min This was to make the strain rates between the ductilometer and the DSR the same

3 0 mm Ligament 7 mm Ligament 4 mm Ligament

4 4 mm Ligament with Plexiglas end tabs ~5mm

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6 SHOWING SPECIMEN REMOVED FROM MOLD

7 SHOWING SPECIMEN MOUNTED IN DSR

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11 680, AA, MTO PAV 4 mm LIG, #, HR , AA, MTO PAV 4 mm LIG, #, HR , AA, MTO PAV 4 mm LIG, #2, HR Strain V (%) (N) Axial force Gap (µm) Step time s (s)

12 680, AA, MTO PAV 7 mm LIG, #, HR , AA, MTO PAV 7 mm LIG, #, HR , AA, MTO PAV 7 mm LIG, #2, HR Strain V (%) 00 (N) Axial force Gap (µm) Step time s (s)

13 680, AA, MTO PAV 7 mm LIG, #, HR (N) Gap (µm) Axial force , AA, MTO PAV 7 mm LIG, #, HR3-680, AA, MTO PAV 4 mm LIG, #2, HR , AA, MTO PAV 0 mm LIG, #2, HR Step time s (s)

14 AB, PG MTO PAV 0 mm Lig, #, HR (N) Gap (µm) Axial force AB, PG MTO PAV 0 mm Lig, #, HR AB, PG MTO PAV 7 mm Lig, #, HR AB, PG MTO PAV 4 mm Lig, #2, HR Step time s (s)

15 Comments Not all samples could be pulled to failure I therefore fit a mathematical model to results where the test did pull to failure and applied that same model to the incomplete data to extrapolate the results to failure

16 25 680, Z, MTO PAV 7 mm LIG, #2, HR , Z, MTO PAV 7 mm LIG, #2, HR3-

17 AB, PG MTO PAV SUMMARY PLOT The dashed line data is based on a modeling of data from a test that reached failure applied to the existing data for these tests AB, PG MTO PAV 4 mm Lig, #, HR AB, PG MTO PAV 4 mm Lig, #2, HR AB, PG MTO PAV 7 mm Lig, #, HR AB, PG MTO PAV 7 mm Lig, #2, HR AB, PG MTO PAV 0 mm Lig, #, HR AB, PG MTO PAV 0 mm Lig, #2, HR3-

18 DENT Test Reporting Sheet PG Grade: Sample : Test Temp. ºC: 5 Date of Test: -Jun-7 MTO PAV MTO Contract: Tested By: GHR RESULTS: Run Run 2 l, measured ligament length mm l, measured ligament length m B, measured sample thickness m Wt, total work of fracture J wt, specific total work of fracture kj/m 2 we, specific essential work of fracture 2.90 kj/m 2 βw p, specific plastic work of fracture 0.59 MJ/m 3 P peak, average for 4mm run 2.00 N δ t, CTOD, average 3.8 mm CHARTS: w t, specific total work (kj/m²) Specific Total Work of Fracture y = x R² = Load (N) E Load Versus Displacement Curves 4mm - Run 4mm - Run 2 7mm - Run 7mm - Run 2 0mm - Run 0mm - Run 2 E E E E E E E E-02 Ligament Length (mm) Displacement (m)

19 DENT Test Reporting Sheet PG Grade: Test Temp. ºC: 5 Date of 5-Jun-7 Test: Sample: MTO PAV MTO Contract: Tested By: GHR RESULTS: Run Run 2 l, measured ligament length mm l, measured ligament length m B, measured sample thickness m Wt, total work of fracture J wt, specific total work of fracture kj/m 2 we, specific essential work of fracture 2.3 kj/m 2 βw p, specific plastic work of fracture 0.28 MJ/m 3 P peak, average for 4mm run.55 N δ t, CTOD, average 5.6 mm CHARTS: 6.00 Specific Total Work of Fracture y = x R² = Load Versus Displacement Curves 4mm - Run 4mm - Run 2 7mm - Run 7mm - Run 2 0mm - Run w t, specific total work (kj/m²) Load (N) mm - Run Ligament Length (mm) E+00.00E E E E E E-02 COMMENTS: Displacement (m)

20 DENT Test Reporting Sheet PG Grade: Test Temp. ºC: 5 Date of 5-Jun-7 Test: Sample: MTO PAV MTO Contract: Tested By: GHR RESULTS: Run Run 2 l, measured ligament length mm l, measured ligament length m B, measured sample thickness m Wt, total work of fracture J wt, specific total work of fracture kj/m 2 we, specific essential work of fracture 3.57 kj/m 2 βw p, specific plastic work of fracture 0.72 MJ/m 3 P peak, average for 4mm run 6.40 N δ t, CTOD, average 6. mm CHARTS: w t, specific total work (kj/m²) Specific Total Work of Fracture y = x R² = Load (N) Load Versus Displacement Curves 4mm - Run 4mm - Run 2 7mm - Run 7mm - Run 2 0mm - Run 0mm - Run 2 COMMENTS: Ligament Length (mm) E+00.00E E E E E E Displacement (m)

21 DENT Test Reporting Sheet PG Grade: Test Temp. ºC: 5 Date of 2-Jun-7 Test: Sample: MTO PAV MTO Contract: Tested By: GHR RESULTS: Run Run 2 l, measured ligament length mm l, measured ligament length m B, measured sample thickness m Wt, total work of fracture J wt, specific total work of fracture kj/m 2 we, specific essential work of fracture 3.0 kj/m 2 βw p, specific plastic work of fracture 0.57 MJ/m 3 P peak, average for 4mm run 8.70 N δ t, CTOD, average 9.6 mm CHARTS: 2.00 Specific Total Work of Fracture y = x R² = Load Versus Displacement Curves 4mm - Run 4mm - Run 2 7mm - Run 7mm - Run 2 0mm - Run w t, specific total work (kj/m²) Load (N) mm - Run Ligament Length (mm) E+00.00E E E E E E COMMENTS: Displacement (m)

22 Comparison of Results Sample MTO 5 C MTE Axial 5C

23 20 8 y = x R² = DENT RESULTS MTO DENT RESULTS DATA Series line of MTO equalitu Linear (Series) Linear (line of MTO equalitu)

24 SUMMARY COMMENTS In theory it is possible to replicate the conventional DENT test and results using much smaller samples on a DSR The DSR has limitations due to normal force transducer and pull distance Could these issues be worked out? Possibly with further changes in sample geometry Would the benefits be worth the effort?

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