NBI Conversion Profiles Enhancement (#1 User Voted Priority)

June 06, 2022

Accuracy of inspection data is key to having confidence in your asset management analysis. Agencies have expressed interest in converted GCR ratings on the inspection in order to improve inspection ratings by  guide inspectors to consider the gap between their GCR rating and the conversion of their elements. The NBI Conversion Profiles enhancement was the highest voted user priority in 2021 and will support this agency direction. The purpose of NBI Conversion profiles are to convert element data to an approximate General Condition Rating (GCR). These converted ratings are then used throughout the optimization process for applicable network policies, lifecycle policies, and performance measures. In the past, agencies were forced to use a one-size-fits-all approach to these conversion profiles. The same threshold of how much condition state 4 constitutes an NBI of 4 was the same for all districts, for all structure types and material types. And while this gets the agency close, it’s not as close as it could be. This improvement will also allow agencies to tighten their accuracy for the varying district practices and for the different structure types (condition state 4 quantities tend to be much worse for pre- stressed concrete beams than for reinforced concrete beams, and so agencies might want a different threshold).

While enhancing this feature, the Task Force will also be allowing the slab elements to convert to both a super and a deck rating—an improvement that helped propel this to the top User Group Request of 2021. FHWA is simultaneously working on some improved recommendations for conversion profiles, and the Task Force will be watching their progress as well to ensure we take their recommendations into consideration. In summary, element conversion is about to experience a quantum leap forward in accuracy and precision.