| Native subgrade |
0.0 |
| Improved subgrade - predominantly granular material |
0.0 |
| Lime modified subgrade of high PI soils |
|
| Granular subbase or base CBR not less than 20 |
0.1 - 0.3 |
| Cement modified subbases and bases constructed from low PI soils |
|
| Cement or lime-fly ash bases with pattern cracking |
0.3 - 0.5 |
| Emulsified or cutback asphalt surfaces and bases with extensive cracking, rutting, etc. |
|
| PCC pavement broken into small pieces |
|
| Asphalt concrete surface and base that exhibit extensive cracking |
0.5 - 0.7 |
| Asphalt concrete generally uncracked |
0.9 - 1.0 |
| PCC pavement stable, undersealed and generally uncracked pavement |
|
| *Equivalent thickness of new asphalt concrete |
|
