1) The Asphalt Institute (MS-1, 1982):

[Ea -0.854 ]

-3.291

where *N*a

=

a function of the volume of the voids and the volume of asphalt, 10z

=

=

4.84 [(Vb/Vv + Vb) 0.69]

=

volume of the asphalt, percent (11%)

=

volume of the voids, percent (5%)

εt

=

tensile strain at the bottom of the asphalt layer, in./in.

modulus of the asphalt layer, lb/in.2

=

2) Witczak (1972) (i.e., Asphalt Institute MS-11):

1.86351 1017

where *a*

=

=

1.01996

=

4.995

=

1.45

pavement temperature, F

=

3) The Corps of Engineers (U.S. Army 1988):

ε t -2.66 log *E*a )

4) Coetzee and Connor (1990):

where when *E*a ≥ 1,500,000 lb/in.2: a, b, c = 3.364 106, 7.370, 4.470

and when *E*a < 1,500,000 lb/in.2: a, b, c = 6.565 106, 5.764, 3.640

1) The Asphalt Institute (1982):

where *N*s

=

allowable traffic based on subgrade strain

=

a constant (0.25)

a constant (2.8 102)

=

εv

=

vertical strain at the top of the subgrade, in./in.

2) The Corps of Engineers (U.S. Army 1987):

where *A *= 0.000247 + 0.00245 log *E*s

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