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IRI units and federal pavement condition

23 CFR 490.313 · FHWA-HIF-18-022 · Paterson (1986) · Al-Omari and Darter (1992)

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IRI units and federal pavement condition

23 CFR 490.313 · FHWA-HIF-18-022 · Paterson (1986) · Al-Omari and Darter (1992)

Convert IRI between in./mi and m/km, and rate a section Good, Fair or Poor by the federal thresholds for national performance reporting (23 CFR 490), from its IRI, cracking and rutting or faulting.

Federal condition (23 CFR 490)

Federal thresholds for national performance reporting, not a state or agency rating.

Percent of the section’s wheel-path area cracked (asphalt), of slabs cracked (jointed concrete) or of the lane with longitudinal cracking or punchouts (CRCP), as HPMS defines it.

Average rut depth of the two wheel paths, inches.

Example values: one asphalt section. Enter the section’s HPMS values; the rating rounds them as FHWA does.

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