Asphalt Institute Method Mechanistic-Empirical Methodology Material - - PDF document

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Asphalt Institute Method

Mechanistic-Empirical Methodology

Structural Models Pavement Response Failure Criteria Trial Layer Thicknesses Material Properties Climate Information Final Layer Thicknesses

Satisfactory

Traffic Information

Unsatisfactory

Mechanistic-Empirical Methodology

Structural Models Pavement Response Failure Criteria Trial Layer Thicknesses Material Properties Climate Information Final Layer Thicknesses

Satisfactory

Traffic Information

Unsatisfactory

Climate Models

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Asphalt Institute Methodology

DAMA (LEA)

max asphalt εt max subgrade εc

Nf (fatigue) Nd (rutting) hac hbs Eac, Ebs, Esg νac, νbs, νsg MAAT (°F) Final Layer Thicknesses

Satisfactory

CR, CP, YW ESALS

Unsatisfactory

Freeze/Thaw Asphalt Temp

Fatigue Failure Criterion

( )

3.291 * 0.854 f t

N 0.0796 E

− −

= ε

Fatigue Failure Criterion

( )

3.291 * 0.854 d 1 2 t

N 0.00432 C C E

− −

= ε

b a b

V 4.84 0.69 V V 2

C 10

⎛ ⎞ − ⎜ ⎟ + ⎝ ⎠

=

1

C 18.4 =

3

Rutting Failure Criterion

( )

4.477 9 d c

N 1.365 10

− −

= × ε

Traffic

( )( )( )( ) ( )

f

ESAL ADT T DL GY 365 T =

Table 6.15 Table 6.13 Table 6.4 Table 6.9 Table 6.10

Asphalt Modulus ( )

( )(

)

3 7 9 10 13

* 1 2 200 4 5 6 log 0.5 8 11 12

log

c c a c c f c b

E c c P f c V c c f c V T c c f

− − + −

= + − + λ + + −

• Vol. air

content % Asphalt viscosity % passing #200 sieve

• Vol. binder

content (%) Asphalt temp. Loading freq.

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Asphalt Modulus ( )

( )(

)

3 7 9 10 13

* 1 2 200 4 5 6 log 0.5 8 11 12

log

c c a c c f c b

E c c P f c V c c f c V T c c f

− − + −

= + − + λ + + −

c1 = 5.553883, c2 = 0.028829, c3 = 0.1703, c4 = 0.03476 c5 = 0.070377, c6 = 0.931757, c7 = 0.02774, c8 = 0.695, c9 = 1.3 c10 = 0.49825, c11 = 0.000005, c12 = 0.00189, c13 = 1.1

Climatic Regions

No 5.0 AC-40 75 Possible 1.6 AC-10, AC-20 60 Yes 0.6 AC-5, AC-10 45 Frost Effects Viscosity, λ (106 poise) Asphalt Grades MAAT (ºF)

Mean Monthly Air Temperatures

54˚F Dec 81˚F Aug 45˚F Apr 58˚F Nov 78˚F Jul 43˚F Mar 73˚F Oct 70˚F Jun 38˚F Feb 78˚F Sept 56˚F May 45˚F Jan

Memphis, TN (MAAT = 60°F)

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Pavement Temperatures

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5 10 15 20 25 30 35 40 08/01/97 08/01/98 08/01/99 08/01/00 08/01/01 Temperature (C) Asphalt Air

Asphalt Temperature

1 34 1 6 4 4

p a

M M z z ⎛ ⎞ = + − + ⎜ ⎟ + + ⎝ ⎠

Mean monthly air temperature (˚F) Mean monthly asphalt temp. (˚F) Depth (in)

Pavement Temperature

5 10 15 20 25 10 20 30 40 50 60 70 80 90 Temperature (F) Depth (in) Air Air Pavement Pavement Ground

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Nonlinear Base Modulus

0.471 0.041 0.139 0.287 0.868 2 1 2 1 3 1

10.447 E h h E E K

− − −

=