Background: Complex ground transportation networks coexist with dynamic river network systems and bridges are a common element at the intersections of these networks. A primary concern for bridge stability is scour, a turbulent physical process in which hydrodynamic forces (e.g., forces from water flow or wind) remove solid material (e.g. soil or rock). In fact, scour is the leading cause of bridge failure in the United States. Bridges that are susceptible to structural damage or failure from scour are termed “scour critical” bridges.

Project Objectives: The objectives of this project are to:

1. Provide the methodology used to determine soil/rock sampling locations and depths, and the soil sampling and testing methods used;
2. Compare scour analysis results using data from different available hydraulic models;
3. Compare scour analyses to analyses of soil samples from the stream bed, and to hydraulic model data; and
4. Conduct a risk assessment, due to scour, for the bridges studied by the project.

Approach: The research involves data collection from available sources, hydraulic modeling, and field data collection. The field data collection consists of topographic and LiDAR surveys, bathymetric surveys, water velocity measurements, and soil sampling. This study will contribute to a greater undersatnding of evaluating bridge scour and ultimately lead to improvements in bridge stability in the state of Missouri.