Flexible Pavement Design - Theory & Concepts

Principles of flexible pavement structure, the AASHTO 1993 design method, Structural Number (SN), and layer thickness calculations.

Traffic (ESALs):5 Million

Subgrade

M_R

:5,000 psi

Lower $M_R$ means weaker soil, requiring a thicker pavement.

Reliability (

R

):90%

Surface (

D_1

a_1 = 0.44

):4"

Base (

D_2

a_2 = 0.14

):6"

Subbase (

D_3

a_3 = 0.11

):8"

Required SN:5.20

Provided SN:3.48

DESIGN INADEQUATE

Increase layer thicknesses to meet the required structural number.

30" -

20" -

10" -

0" -

HMA Surface (4")

Base Course (6")

Subbase (8")

Subgrade

M_R

= 5,000 psi

Related simulations