Author(s): Timothy Calappi; Carol J. Miller; Donald Carpenter
Linked Author(s): Donald Carpenter
Keywords: No Keywords
Abstract: This study provides an analysis of long-term, cumulative, pier scour at two Michigan bridge crossings. The analysis relies on data from a recent Michigan Department of Transportation (MDOT) investigation of bridge scour. For each of the analyzed sites, MDOT as-built drawings, soil borings, flow data, and periodic channel surveys are available. In addition, present-day channel bathymetry has been collected in the vicinity of piers. The various data is assembled to provide the scour scenario, over time, for each bridge crossing. The cumulative scour, over 15 year time periods, is predicted for each bridge using the episodic formulations in an additive mode using the CSU scour equation as well as a stream power formulation. The predicted cumulative scour is compared to the field observations. The comparison between the predicted and observed cumulative scour over the life of the bridge provides important insight, especially in two considerations. The first consideration relates to the repeated use of the episodic scour equation for cumulative predictions. The second consideration relates to the importance of the continual scour that occurs over time for non-flood events.
Year: 2009