ltrc project no. 11-2b (emulsions) southern plains ... research... · (aashto t301) and force...

Replacement of Elastic Recovery (AASHTO T301) and Force Ductility

(AASHTO 300) Tests by DSR-Based Tests

LTRC Project No. 11-2B (Emulsions)

Southern Plains Transportation

Center (SPTC) Project No. 14.1-80

(Binders)

By

N. Wasiuddin

Louisiana Tech University

Objectives:

• Characterization of asphalt emulsion residues with

DSR tests:

• Strain sweep

• Frequency sweep

• Temperature sweep

• Multiple Stress Creep and Recovery (MSCR)

• Evaluation of correlations with:

• Elastic recovery • Force ductility

Why PG-Plus tests:

To identify the presence of polymers and quantify its

beneficial effects

PG-Plus tests:

• Elastic Recovery

• Force Ductility

• Phase Angle

• Toughness and Tenacity, etc.

are being used by

LA DOTD

States that are using PG-Plus tests (Green

States as prepared in Google chart)

Elastic Recovery Test (AASHTO T301) and

Force Ductility Test (AASHTO T300)

Ductility Bath

Elastic Recovery and

Force Ductility molds

Elastic Recovery

sample after severing Force Ductility sample

under test

20 cm

After pulling apart

Sever at the middle

after 5 minutes

(20- X) cm

After 1 hour

Elastic Recovery % = (20 – X) *100

20

Primary shape of briquette

Elastic Recovery Measurements:

Force Ductility Measurements:

The ratio of f2/f1 or f2 at 30 cm

f1

f2

In case of two maximum points

f1

f2

In case of one maximum point

Survey of Elastic Recovery Test Methods:

State Modified PG Binder Modified Emulsion

Asphalt

California AASHTO

T301(20cm&25°c)

AASHTO T51(25°c)

West Virginia AASHTO

T301(20cm&25°c)

-

Kentucky AASHTO

T301(10cm&25°c)

AASHTO

T301(10cm&4°c)

New Jersey ASTM

D6084(20cm&25°c)

AASHTO

T301(20cm&10°c)

Tennessee AASHTO

T301(20cm&25°c)

AASHTO

T301(20cm&10°c)

Texas ASTM

D6084(20cm&10°c)

TEX-539-C(20cm&10°c)

Louisiana AASHTO

T301(10cm&25°c)-2016

AASHTO

T301(20cm&10°c)

Survey of Force Ductility Test Methods (Illinois):

Test

SBS PG 64-28

SBS PG 70-22

SBS PG 70-28

SBS PG 76-22

SBS PG 76-28

Force Ratio (f2/f1),

4⁰c, 50mm/min.,

300 mm

elongation,

minimum

0.3 0.35

Survey of Force Ductility Test Methods (Louisiana):

Test PG 76-22m PG 70-22m

CRS-2P SS-1P PAC 15

Force Ratio

(f2/f1), 4⁰c,

50mm/min., 300

mm elongation,

minimum

0.3 _ 0.3 0.15 0.3

Force Ductility,

4⁰c, 50mm/sec,

300 mm

elongation, kg,

minimum

_ 0.23 - - -

MSCR Test Parameters (ASTM D7405):

Stress Levels of 100 and 3200 Pa, 10 Cycles, Creep Stress 1s, Recovery

9s

0

10

20

30

40

50

60

70

0 2 4 6 8 10 12

Str

ain

(%

)

Time (s)

One Cycle of MSCR Test

Ƴp peak strain

Ƴr recovered strain

Ƴu unrecovered strain

Percent of Recovery (%) = (Ƴr / Ƴp ) x 100 Non-Recoverable Creep Compliance (Jnr) = Ƴu /ơ

Why MSCR test instead of PG-Plus tests:

• Different states apply different methods and criteria for Elastic

Recovery and Force Ductility tests

• MSCR Test uses the same DSR device : No additional cost

• Easy and time saving

• Repeatability

• Less variability due to operator

• Small

• Mechanistic

20 Asphalt Emulsions were investigated

• Polymer Modified Emulsions:

PME

CHFRS-2P

CRS-2P (E)

CRS-2P (B)

CMS-1P

SS-1L

• Hard Pen Base Emulsions:

SS-1H (B)

SS-1H (U)

NTSS-1HM (C)

NTSS-1HM (B)

NTSS-1HM (U)

FOG SEAL

• Polymer Modified Hard Pen Base Emulsions:

CSS-1HP

SS-1HP

• Non Polymer Modified Non Hard Pen Base Emulsions:

CRS-2 (E)

CRS-2 (B)

CRS-2 (U)

SS-1 (E)

SS-1 (B)

SS-1 (U)

Emulsions Strain

Sweep

Freq. Sweep Temp. Sweep MSCR Elastic

Recovery

and Force

Ductility

SS-1 (E)

Temp.: 52°C

and 70°C

Strain:

2%, 12%,

22%, 32%,

42% and

52%

3 mat

samples

Temp.: 10°C, 25°C, 58°C

and 70°C

Ang. Freq.:

0.1 rad/s – 100

rad/s

3 mat samples

Temp.: from 52°C to

94°C at 6°C

intervals

Strain and

Ang. Freq.:

12% and 10

rad/s

3 mat samples

and

3 DSR mold

samples

Temp.: 10°C, 25°C, 58°C,

70°C and one

equal-stiffness

temperature (2.2

kPa stiffness)

Stress:

0.1kPa, 3.2 kPa

(0.1kPa, 0.2 kPa,

0.5 kPa and 3.2

kPa at 2.2 kPa

stiffness temp.)

3 mat samples for

0.1 and 3.2 kPa

and 3 mat

samples2 for 0.2

and 0.5 kPa

Temp.

Elastic

Recovery: 10°C and

25°C

Temp.

Force

Ductility: 4°C

2 mat

Samples

for Elastic

Recovery

and 2 mat

samples

for Force

Ductility

SS-1 (B)

SS-1 (U)

SS-1H (B)

SS-1H (U)

SS-1HP

SS-1L

CRS-2 (E)

CRS-2 (B)

CRS-2 (U)

CRS-2P (E)

CRS-2P (B)

CHFRS-2P

CMS-1P

CSS-1HP

PME

NTSS-1HM (B)

NTSS-1HM (C)

NTSS-1HM (U)

Fog Seal

Experimental Plan

Recovering Residue from Emulsified Asphalt:

• Low temperature evaporative technique (ASTM D7497)

• Elastic Recovery Test : 24 hours at 25⁰C forced oven + 24 hours at

60⁰C forced oven

• DSR-based Test : 24 hours at 25⁰C forced oven + 24 hours at

60⁰C forced oven

•Force Ductility Test : 6 hours at 60⁰C forced oven

Sample preparation for Elastic Recovery and Force Ductility

Tests:

1 2 3

4 5 6

7 8 9

10 11 12

Sample preparation for DSR-based Tests :

1

4

7

10

2

5

8

11

3

6

9

12

Strain Sweep Test:

• Strain Sweep Test was conducted at two temperatures, 52⁰C and 70⁰C,

and six strains , 2%, 12%, 22%, 32% , 42% and 52%

• Drop from Initial G*% = 100* (G*2% - G*52%)/(G*2%)

• The lower the drop, the higher the strain tolerance

• Indication of linearity

•Drop from initial G* can be used as a criteria to estimate aggregate loss in

chip seals

•Polymer Modified

Emulsions:

PME

CHFRS-2P

CRS-2P (E)

CRS-2P (B)

CMS-1P SS-1L

Strain Sweep Test:

• The maximum of tolerance at 52⁰C and 70 ⁰C are 12.9% and

16.4% respectively for SS-1L

• The minimum of tolerance at 52⁰C and 70 ⁰C are 3.4% and 1.9%

respectively for CMS-1P

•Hard Pen Base

Emulsions:

SS-1H (B)

SS-1H (U)

NTSS-1HM (C)

NTSS-1HM (B)

NTSS-1HM (U)

FOG SEAL

Strain Sweep Test:

• NTSS-1HM(C), NTSS-1HM(B) and FOG SEAL could not reach 52% strain at 52⁰C

• The maximum of tolerance at 52⁰C and 70 ⁰C are 44.2% and 43.3%

respectively for NTSS-1HM(U) and NTSS-1HM(B) • The minimum of tolerance at 52⁰C and 70 ⁰C are 15% and 1.2%

respectively for SS-1H(U)

•Polymer Modified and

Hard Pen Base Emulsions:

CSS-1HP

SS-1HP

Strain Sweep Test:


respectively for CSS-1HP


respectively for SS-1HP

•Non Polymer Modified and

Non Hard Pen Base

Emulsions:

CRS-2 (U)

CRS-2 (E)

CRS-2 (B)

SS-1 (E)

SS-1 (B)

SS-1 (U)

Strain Sweep Test:


respectively for SS-(E)


respectively for CRS-2(B) and SS-1(B)

Strain Sweep Test:

In Summary:

• Higher drop from initial G* or lower strain tolerance will result in

increase of aggregate loss in chip seals

• Asphalt emulsions prepared of hard pen base asphalt have higher

drop from initial G* or lower strain tolerance

Frequency Sweep Test:

• Master curve was constructed at 25⁰ C based on conducted

frequency sweep tests at 10⁰C, 25⁰C, 58⁰C and 70⁰C. • Master curve is used to understand the overall rheological behavior

of asphalt emulsions.

Master

Curve

Master Curve:

• NTSS-1HM (C), NTSS-

1HM (U) and Fog Seal

show high G* values in a wide range of frequencies

Master Curve:

• NTSS-1HM (B) shows

high G* value in a wide range of frequencies

Frequency Sweep Test:

In Summary:

• Hard Pen Base Emulsions show higher G* value and lower strain

tolerance

Temperature Sweep Test:

• Temperature Sweep Test of DSR was conducted on emulsion residues

from 52⁰C to 94⁰C at 6⁰C intervals.

• Results of Temperature Sweep Test include:

Diagram of G*/Sin(δ) versus Temperature

Diagram of Phase Angle(δ) versus Temperature

Temperature Sweep Test: G*/Sin(δ) versus Temperature

• Hard Pen Base emulsions

including NTSS-1HM (B) and

CSS-1HP have the higher

G*/Sin δ than other emulsions.

NTSS-1HM (B)

CSS-1HP

Temperature Sweep Test: G*/Sin(δ) versus Temperature

• Hard Pen Base emulsions such

as NTSS-1HM (C), NTSS-1HM

(U) and Fog Seal have the higher

G*/Sin δ than other emulsions.

.

FOG SEAL

NTSS-1HM (C)

NTSS-1HM (U)

Temperature Sweep Test: Phase Angle(δ) versus

Temperature

• When temperature increases,

phase angle increases to a

maximum and then decreases.

• the maximum phase angle of all

the non-hard pen polymer modified

asphalt emulsion residues fall between 75⁰ to 85⁰.

Temperature Sweep Test: Phase Angle(δ) versus

Temperature

• When temperature increases,

phase angle increases to a

maximum and then decreases.

• the maximum phase angle of all

the non-hard pen polymer modified

asphalt emulsion residue falls between 75⁰ to 85⁰.

Elastic Recovery Test (AASHTO T301):

10⁰C 25⁰C

Average Elastic

Recovery (%)

Modified

Emulsions

Modified

Emulsions

MSCR Test Results:

Emulsions

Percent Recovery (MSCR)

Creep Stress 0.1 kPa Creep Stress 3.2 kPa

10°C 25°C 58°C 70°C 10°C 25°C 58°C 70°C

Polymer Modified Emulsions

CMS-1P 58.8 46.9 35.1 29.0 57.8 45.1 12.6 -1.9

CRS-2P (B) 60.2 48.1 25.9 21.7 58.1 46.2 9.8 0.9

CRS-2P (E ) 76.0 63.0 29.7 30.3 65.9 62.7 9.5 2.2

SS-1L 66.7 58.2 53.1 35.6 62.9 56.8 13.9 0.7

PME 79.5 60.0 36.0 32.0 67.4 60.0 12.2 0.4

CHFRS-2P 72.7 67.5 36.8 38.1 72.8 67.4 17.1 5.2

Polymer Modified and Hard Pen Base Asphalt Emulsions

CSS-1HP 99.9 81.4 56.7 76.3 73.3 76.9 36.2 10.4

SS-1HP 75.9 68.7 24.1 8.7 73.2 68.7 12.9 1.3

MSCR Test Results:

Emulsions



10°C 25°C 58°C 70°C 10°C 25°C 58°C 70°C

Non-Polymer Modified and Non-Hard Pen Base Asphalt Emulsions

SS-1 (B) 66.1 44.2 3.7 -1.8 66.1 43.4 0.0 -2.7

SS-1 (E ) 66.1 39.8 4.9 -1.1 67.4 37.6 -0.1 -2.6

SS-1 (U) 54.4 41.1 5.4 -0.1 52.8 38.5 -0.1 -2.7

CRS-2 (U) 51.1 34.9 2.9 -1.9 51.7 38.5 -0.2 -2.9

CRS-2 (B) 55.5 37.9 7.7 0.6 52.4 37.3 0.2 -2.6

CRS-2 (E ) 59.9 49.0 7.1 0.5 63.1 51.0 0.4 -2.6

MSCR Test Results:

Emulsions



10°C 25°C 58°C 70°C 10°C 25°C 58°C 70°C

Hard Pen Base Asphalt Emulsions

SS-1H (U) 72.1 59.0 6.5 2.4 73.5 58.5 3.4 -0.1

SS-1H (B) 96.6 63.4 11.6 4.0 80.7 63.6 5.3 0.2

NTSS-1HM

(U) >100 67.5 12.8 8.8 90.0 68.9 9.7 1.6

NTSS-1HM

(C ) >100 >100 25.8 13.5 >100 72.1 24.2 10.2

NTSS-1HM

(B) >100 >100 39.7 33.0 >100 >100 45.1 28.1

FOG SEAL >100 >100 27.0 14.3 96.9 >100 26.8 12.1

MSCR Test Results:

Emulsions

2.2 kPa

Stiffness

(G*/sinδ)

Temperatures

°C)

Creep Stresses (kPa) R2 Value for

Log(stress)

vs. Percent

Recovery

0.1 0.2 0.5 3.2


CRS-2P (E) 63°C 27.5 24.6 13.9 1.5 0.98

SS-1L 61°C 60.6 55.4 38.8 7.4 0.99

CHFRS-2P 67°C 34.3 29.8 18.6 2.2 0.99

CMS-1P 55°C 43.0 45.6 37.5 23.3 0.91

CRS-2P (B) 59°C 16.5 19.0 13.1 3.7 0.88

PME 62°C 44.2 39.7 26.1 4.1 0.99


CSS-1HP 80°C 92.2 86.7 47.5 1.1 0.98

SS-1HP 66°C 11.4 8.7 5.5 0.8 0.99

MSCR Test:

Emulsions

2.2 kPa

Stiffness

(G*/sinδ)

Temperatures

°C)


Log(stress)

vs. Percent

Recovery

0.1 0.2 0.5 3.2

Non-Polymer Modified and Non Hard Pen Base Asphalt Emulsions

CRS-2 (U) 56°C 6.2 4.1 1.9 -0.3 0.95

CRS-2 (B) 57°C 7.7 6.0 3.4 0.0 0.99

CRS-2 (E) 57°C 5.7 3.9 2.0 -0.2 0.96

SS-1 (U) 57°C 8.4 5.7 2.5 -0.3 0.95

SS-1 (B) 57°C 5.9 5.8 3.2 0.5 0.96

SS-1 (E) 57°C 8.7 6.0 2.6 -0.3 0.94

MSCR Test Results:

Emulsions

2.2 kPa

Stiffness

(G*/sinδ)

Temperatures

°C)


Log(stress)

vs. Percent

Recovery

0.1 0.2 0.5 3.2


SS-1H (U) 68°C 4.2 2.8 1.2 -0.3 0.95

SS-1H (B) 68°C 10.7 7.6 3.6 0.0 0.95

Fog Seal 94°C 8.6 6.4 3.2 0.2 0.96

NTSS-1HM

(U) 79°C 13.3 9.2 3.8 -0.4 0.94

NTSS-1HM

(B) 96°C 21.1 15.7 7.5 0.3 0.96

NTSS-1HM

(C) 90°C 15.7 12.3 6.8 0.6 0.98

Correlation between MSCR parameters and Elastic

Recovery

Coefficient of Determination (R2) for Linear Correlation Between

Percent Recovery (MSCR) and Elastic Recovery (AASHTO

T301)

MSCR Temperature MSCR Creep

Stress

Elastic Recovery

Temperature (AASHT

T301)

10°C 25°C

58°C 0.1 kPa 0.961 0.798

3.2 kPa 0.938 0.843

70°C 0.1 kPa 0.957 0.872

3.2 kPa 0.516 0.493

2.2 kPa Stiffness

Temperature

0.1 kPa 0.908 0.692

3.2 kPa 0.409 0.487

Correlation between MSCR parameters and Elastic

Recovery

Coefficient of Determination (R2) for Linear Correlation Between

Non-Recoverable Creep Compliance, Jnr (MSCR) and Elastic

Recovery (AASHTO T301)

MSCR Temperature MSCR Creep

Stress

Elastic Recovery

Temperature

(AASHTO T301)

10°C 25°C

58°C 0.1 kPa 0.737 0.623

3.2 kPa 0.604 0.472

70°C 0.1 kPa 0.169 0.696

3.2 kPa 0.502 0.391

2.2 kPa Stiffness

Temperature

0.1 kPa 0.734 0.682

3.2 kPa 0.078 0.139

Linear correlation between percent recovery (MSCR at 58°C)

and elastic recovery

Linear correlation between percent recovery (MSCR at

2.2 kPa temperature) and elastic recovery

Linear correlation between percent recovery (MSCR at 70°C)

and elastic recovery

Force Ductility Test:

Emulsions Max. Force, f1

(lb)

Force at 30 cm, f2

(lb) f2/f1

Force at 35 cm

(lb)

Avg. St. Dev. Avg. St. Dev. Avg. St. Dev. Avg. St. Dev.


CHFRS-2p 5.3 0.3 0.38 0.05 0.07 0.01 0.35 0.03

CMS-1p 1.8 0 0.22 0.02 0.12 0.01 0.26 0.01

CRS-2P (E ) 5.9 0.1 0.4 0.07 0.07 0.01 0.36 0.06

PME 4.1 0.2 0.1 0.04 0.03 0.01 0.07 0.03

SS-1L 5.3 0.2 0.19 0.04 0.04 0.01 0.15 0.02

Non-Polymer Modified and Non-Hard Pen Base Asphalt Emulsions

CRS-2 (U) 8.7 0.7 0.06 0.08 0.01 0.01 0.02 0.03

CRS-2 (E ) 4.2 0.1 0 0 0 0 0 0

SS-1 (U) 4.3 0.02 0 0 0 0 0 0

SS-1 (B) 6.2 0.02 0.04 0 0.01 0 0 0

SS-1 (E ) 2.7 1

sample 0.06

1

sample 0.02

1

sample 0.03

1

sample


Emulsions Max. Force, f1

(lb)

Force at 30 cm, f2

(lb) f2/f1

Force at 35 cm

(lb)

Avg. St. Dev. Avg. St. Dev. Avg. St. Dev. Avg. St. Dev.


SS-1H (U) 19.4 0.6 0 0 0 0 0 0

SS-1H (B) 13.8 1.2 0 0 0 0 0 0

Fog Seal 4.3 1

sample 0 0 0 0 0 0

NTSS-1HM

(U) 41.2 7.4 0 0 0 0 0 0

NTSS-1HM

(B) 18.7 6.2 0 0 0 0 0 0


CSS-1HP 11.2 1.6 0 0 0 0 0 0

SS-1HP 9.2 0.05 2.13 0.11 0.23 0.01 0.89 1.26


Linear Correlation with Phase Angle

Force Ductility

Test Parameter

Phase Angle Testing Temperature

58°C 70°C 2.2kPa Temp. Average R2

Force at 30 cm, f2

(lb) 0.71 0.52 0.62 0.62

f2/f1 0.47 0.74 0.47 0.56

Force at 35 cm

(lb) 0.69 0.61 0.62 0.64

Average R2 0.62 0.62 0.57 0.61

Linear Correlation with Percent Recovery

Force Ductility

Test Parameter

Percent Recovery (at 0.1 kPa Creep

Stress) Testing Temperature

58°C 70°C 2.2kPa Temp. Average R2

Force at 30 cm, f2

(lb) 0.46 0.65 0.31 0.47

f2/f1 0.43 0.54 0.38 0.45

Force at 35 cm

(lb) 0.46 0.66 0.33 0.48

Average R2 0.45 0.62 0.34 0.47

Recommendations:

• MSCR (ASTM D7405) has been recommended to replace Elastic

Recovery test (AASHTO T301) to identify the presence of polymer.

Residue should be prepared according to ASTM D7497.

Test Specifications

Minimum Percent Recovery,

58⁰C, 0.1 kPa creep stress 25

Minimum Percent Recovery,

MSCR, 58⁰C, 3.2 kPa creep

stress 9

Recommendations:

• Percent recovery of MSCR and phase angle can be used to

replace force ductility requirements (AASHTO T300).

Test Specifications

Minimum Percent Recovery, MSCR at

58⁰C, 0.1kPa creep stress

&

Maximum Phase angle, 58⁰C, 12% strain,

10 rad/sec

30

81⁰

ltrc project no. 11-2b (emulsions) southern plains ... research... · (aashto t301) and force...

Documents