Design and Evaluation of Scour for Bridges Using HEC-18 (Volume 1 of 3).

PDFTech ReportFHWA-NJ-2017-011NJDOT TO-89BridgesScourMathematical modelsGeotechnical engineeringHydrologyData analysisErosionSedimentsCurves (Geometry)Scour Evaluation ModelSEMNew JerseyUnited StatesNew Jersey Institute of TechnologySchuring, John R.Dresnack, RobertGolub, EugeneNew Jersey Institute of Technology. Dept. of Civil & Environmental EngineeringNew Jersey. Dept. of TransportationUnited States. Federal Highway AdministrationShah, PragnaNTL-ENERGY AND ENVIRONMENT-Environment ImpactsNTL-HIGHWAY/ROAD TRANSPORTATION-Soils and GeologyNTL-HIGHWAY/ROAD TRANSPORTATION-Bridges and StructuresUS Transportation CollectionThe overall objective of this research is the development of a new approach for evaluating bridge scour for New Jersey's bridges on non-tidal waterways. The study commenced with a web-based survey of scour practice within the U.S. and a literature review of predictive scour models. The major project deliverable is a new Scour Evaluation Model (SEM), which is a tiered, parametric, risk-based decision tool. A variety of geo-technical, hydrologic, and hydraulic data are analyzed to generate risk ratings for a particular bridge. These ratings are then inputted into a Risk Decision Matrix to generate a scour priority level and recommended actions, which may range from expedited installation of countermeasures to removal from scour critical status. Bridge importance is also factored into the final priority level. In addition, the New Jersey SEM provides standard protocols for: (1) erosion classification of sediments; (2) application of scour envelope curves; and (3) analysis of hydrologic data. The model was validated and calibrated by inspecting scour critical bridges and comparing actual field observations with model results. While the current model reflects New Jersey\u2019s geology and hydrology, it can be recalibrated to other regions or states. The model is principally designed to evaluate scour risk of existing bridges, but many model components are useful for designing new bridges as well. Included are example SEM applications for 12 bridges and two detailed example problems