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Pavement Aashto: natural gravel subbase
AASHTO pavement design material properties including layer coefficients, drainage coefficients, and modulus values for flexible and rigid pavement design
| material id | description | drainage coefficient max (dimensionless) | drainage coefficient min (dimensionless) | layer coefficient | layer type | material name | max thickness in | min thickness in (in) | standard | typical modulus MPa (MPa) | typical modulus psi (psi) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| natural gravel subbase | Natural gravel subbase (CBR >= 15) | 1.4 | 0.4 | 0.09 | subbase | Natural Gravel Subbase | 12 | 4 | AASHTO Guide for Design of Pavement Structures (1993) | 83 | 12,000 |
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