Table 2.
Explanation of input variables.
| Category | Variable | Explanation | Unit |
|---|---|---|---|
| Structure | Thickness | The total thickness of pavement | mm |
| Performance | Gator | Area of alligator (fatigue) cracking. | m2 |
| Block | Area of block cracking. | m2 | |
| Edge | Length of low severity edge cracking. | m | |
| Long-wp | Length longitudinal cracking in wheel path. | m | |
| Long-nwp | Length non-wheel path longitudinal cracking. | m | |
| Transverse | Length of transverse cracking. | m | |
| Patch | Area of patching | m2 | |
| Potholes | Area of potholes | m2 | |
| Shoving | Area of shoving, localized longitudinal displacement of the pavement surface. | m2 | |
| Bleeding | Presence of excess asphalt on the pavement surface which may create a shiny, glass-like reflective surface. | m2 | |
| Polish | Area of polished aggregate (binder worn away to expose coarse aggregate). | m2 | |
| Raveling | Wearing away of the pavement surface caused by the dislodging of aggregate particles and loss of asphalt binder. | m2 | |
| Rut | Depth of rut | mm | |
| IRI0 | The first IRI when the road is put into use | m/Km | |
| Age | Road service time | \ | |
| Traffic | AADTT | Average annual daily truck traffic | \ |
| ESAL | The annual average of equivalent single axle load in the LTPP lane. | \ | |
| Climatic | Freeze | Annual average freeze index | \ |
| Precipitation | Annual average precipitation | mm |