In compliance with regulations from the Federal Highway Administration (FHWA), the South Carolina Department of Transportation (SCDOT) set out to determine a current load rating for each of its bridges. These ratings would give SCDOT the information they would need to set appropriate weight-limit restrictions and prioritize bridge replacements and repairs. Davis & Floyd, in association with Michael Baker International, was selected to load rate approximately 567 concrete slab bridges in District 3. To produce these ratings, Davis & Floyd executed the procedures outlined in the newly released SCDOT Load Rating Guidance Document, a set of instructions that ensure compliance with federal regulations. With this data, Davis & Floyd was proud to contribute to SCDOT’s effort to reduce the percentage of structurally deficient bridges in the state.

Davis & Floyd identified an efficient method of data collection by reviewing existing design plans, as-built plans, previous inspection reports, and SCDOT standard plans. Our team conducted site assessments to verify bridge dimensions and conditions of structural components as well as documented additional characteristics that contributed to overall load-carrying capacity.

Our team of structural engineers used this data to calculate the load rating factors for each bridge while considering over 40 different loading scenarios and rating levels. Using these factors, our team identified bridges that did not meet the load-carrying capacity for current regulations in South Carolina and provided SCDOT with recommendations for new weight restrictions. Using the data collected, we provided recommendations to update the National Bridge Inventory (NBI), documenting the current conditions of each bridge.


  • Bridge Load Rating 

  • Structural Engineering