Measurement of scour-depth near bridge piers
Water-Resources Investigations Report 85-4106
Prepared in cooperation with the Federal Highway Association
- J.V. Skinner
River-bed scour is a major source of damage to bridge piers and bridge abutments. When scour depth exceeds design limits, the supporting material around the footings is washed away and the structure becomes unstable. Equations for predicting scour-depth show a significant lack of agreement so portable equipment for measuring scour is needed.
This report discusses the design of an instrumented, unmanned boat that (a) can be launched and controlled from a bridge and (b) can be maneuvered in flood flows that reach velocities of 15 feet per second. Calculations indicate the battery-powered propulsive system alone will weigh about 300 pounds and that the craft must be about 15-feet long.
Because a free-running craft will be undesirably heavy and large, other methods of obtaining scour data are proposed. A tethered craft fitted with a controllable rudder and some methods of measuring scour at a point are presented for future study and development.
Additional publication details
- Publication type:
- Publication Subtype:
- USGS Numbered Series
- Measurement of scour-depth near bridge piers
- Series title:
- Water-Resources Investigations Report
- Series number:
- Year Published:
- U.S. Geological Survey
- Publisher location:
- Minneapolis, MN
- Contributing office(s):
- Minnesota Water Science Center
- iv, 33 p.
- Online Only (Y/N):
- Additional Online Files (Y/N):