Asphalt Institute Method Mechanistic-Empirical Methodology Material - PDF document

Asphalt Institute Method

Mechanistic-Empirical Methodology Material Trial Layer Properties Thicknesses Structural Models Climate Pavement Traffic Information Response Information Failure Criteria Satisfactory Unsatisfactory Final Layer Thicknesses

Mechanistic-Empirical Methodology Material Trial Layer Properties Thicknesses Climate Structural Models Models Climate Pavement Traffic Response Information Information Failure Criteria Satisfactory Unsatisfactory Final Layer Thicknesses

Asphalt Institute Methodology E ac , E bs , E sg h ac ν ac , ν bs , ν sg h bs Freeze/Thaw DAMA (LEA) Asphalt Temp max asphalt ε t MAAT CR, CP, YW max subgrade ε c (°F) ESALS N f (fatigue) N d (rutting) Satisfactory Unsatisfactory Final Layer Thicknesses

Fatigue Failure Criterion 0.854 − * E 3.291 − ) t ε ( 0.0796 = f N

Fatigue Failure Criterion ( ) − − = ε 3.291 * 0.854 N 0.00432 C C E d 1 2 t = C 18.4 1 ⎛ ⎞ V − b 4.84 ⎜ 0.69 ⎟ + = ⎝ ⎠ V V C 10 a b 2

Rutting Failure Criterion 4.477 − ) c ε ( 9 − 1.365 10 × = d N

Traffic Table 6.15 ( )( )( )( ) ( ) = ESAL ADT T DL GY 365 T f Table 6.13 Table 6.4 Table 6.9 Table 6.10

Asphalt Modulus % passing Vol. air Asphalt #200 sieve content % viscosity ( ) − − = + − + λ + * c c log E c c P f c V c c f 3 7 1 2 200 4 5 6 a ) ( ) ( + − + − c c log f 0.5 c c V T c c f 9 10 13 8 b 11 12 Vol. binder Asphalt Loading content (%) temp. freq.

Asphalt Modulus ( ) − − = + − + λ + * c c log E c c P f c V c c f 3 7 1 2 200 4 a 5 6 ) ( ) ( + − + − c c log f 0.5 c c V T c c f 9 10 13 8 11 12 b c 1 = 5.553883, c 2 = 0.028829, c 3 = 0.1703, c 4 = 0.03476 c 5 = 0.070377, c 6 = 0.931757, c 7 = 0.02774, c 8 = 0.695, c 9 = 1.3 c 10 = 0.49825, c 11 = 0.000005, c 12 = 0.00189, c 13 = 1.1

Climatic Regions Viscosity, λ MAAT Asphalt Frost (10 6 poise) (ºF) Grades Effects 45 AC-5, AC-10 0.6 Yes 60 AC-10, AC-20 1.6 Possible 75 AC-40 5.0 No

Mean Monthly Air Temperatures Memphis, TN (MAAT = 60°F) Jan 45˚F May 56˚F Sept 78˚F Feb 38˚F Jun 70˚F Oct 73˚F Mar 43˚F Jul 78˚F Nov 58˚F 45˚F 81˚F 54˚F Apr Aug Dec

Pavement Temperatures 40 35 Asphalt Air 30 25 Temperature (C) 20 15 10 5 0 -5 08/01/97 08/01/98 08/01/99 08/01/00 08/01/01

Asphalt Temperature Mean monthly air temperature (˚F) ⎛ ⎞ 1 34 = + − + ⎜ ⎟ 1 6 M M + + p a ⎝ ⎠ 4 4 z z Mean monthly asphalt temp. (˚F) Depth (in)

Pavement Temperature Temperature (F) 0 10 20 30 40 50 60 70 80 90 0 5 Air Pavement Air Pavement 10 Depth (in) 15 20 Ground 25

Nonlinear Base Modulus − − − = 0.471 0.041 0.139 0.287 0.868 10.447 E h h E E K 2 1 2 1 3 1