Research Article

Prediction of Bridge Component Ratings Using Ordinal Logistic Regression Model

Table 1

Condition ratings used in the National Bridge Inventory (NBI).

CodeMeaningDescription

9ExcellentAs new

8Very GoodNo problems noted.

7GoodSome minor problems.

6SatisfactoryStructural elements show some minor deterioration.

5FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.

4PoorAdvanced section loss, deterioration, spalling or scour.

3SeriousLoss of section, deterioration, spalling or scour has seriously affected primary structural components. Local failures are possible. Fatigue cracks in steel or shear cracks in concrete may be present.

2CriticalAdvanced deterioration of primary structural elements. Fatigue cracks in steel or shear cracks in concrete may be present or scour may have removed substructure support. Unless closely monitored it may be necessary to close the bridge until corrective action is taken.

1Imminent FailureMajor deterioration or section loss present in critical structural components or obvious vertical or horizontal movement affecting structure stability. Bridge is closed to traffic but with corrective action may put back in light service.

0FailedOut of service, beyond corrective action.

Source: United States Department of Transportation. Recording and Coding Guide for the Structure Inventory and Appraisal of the Nation's Bridges. Washington, D.C., 1995, page 38.