BackgroundCost effective and secure highway bridge designs are required to ensure the long-term sustainability of Virginia’s road systems. The streamflows that,over time, scour streambed sediments from bridge piers inherently affect bridge safety and design costs. To ensure safety, and bridge design must anticipate streambed scour at bridge piers over the lifespan of a bridge. Until recently Federal Highway Administration (FHWA) guidance provided only for scour estimates of granular,noncohesive, highly erosive fabric yielding overestimates of scour potential in instances when streambed materials offer some resistance to scour. This study seeks to estimate stream power and streambed scour for these more resistive sites, or with bridge piers potentially established in cohesive soil or erodible rock. This unique knowledge may provide significant construction cost savings while ensuring design and construction of secure highway bridges.
Source: usgs.gov