NTL Record

Title Remote Methods of Underwater Inspection of Bridge Structures
Record ID 79328
Personal Name
Creator
Bath, W. R.
Personal Name
Contributor
Rodriguez, Carlos M; Jones, Sterling; Bertoldi, David A.; Pearson, Donna
Corporate Creator Sonsub Inc.
Corporate
Contributor
United States. Department of Transportation. Federal Highway Administration. Office of Infrastructure Research and Development
Publisher United States. Federal Highway Administration
Publication Date 19990701
Language English
Abstract A portable trailer mounted bridge scour inspector was developed and tested under flood conditions for inspecting bridge scour in the vicinity of piers from the bridge deck. The bridge scour inspector features a remotely controlled arm to deploy a sonar probe in the water from a vehicle located on the bridge deck. The arm can be fixed in a cross section mode to take cross sections immediatedly upstream and downstream of a bridge or it can be maneuvered in the vicinity of piers including some distance under the bridge deck to inspect for deep local scour holes. Two servo motors constantly adjust the orientation of the sonar probe to maintain a vertical beam. A mechanical positioning system tracks the X,Y,Z coordinates of the sonar probe wherever it is in the water relative to some reference location on the pridge deck. The bridge scour inspector was field tested under low water condition in Texas and was field tested under extreme flood conditions in Georgia during the 1994 Tropical Storm Alberta flooding. Limitations of the bridge scour inspector include the max distance of 15 meters (50 feet) that the arm can be extended below the bridge deck to reach water, a minimum distance of 4.5 meters (15 feet) needed to avoid total submergence and possible malfunction of servo motor controls, and operation difficulties on truss type bridges because the arm must be retracted each time it passes an elevated obstruction. It is a viable bridge scour inspection device for many bridges during extreme flood conditions when it is too dangerous to put a boat in the water. A more sophisticated remotely controlled work station was designed conceptually and is desribed in the report but it was not fabricated for testing. This system could be used above and below the water surface to inspect and repair bridges.
Rosap ID dot:54090
Rosap URL https://rosap.ntl.bts.gov/view/dot/54090
TRT Terms Scour; Inspection; Robotics; Bridges; Remote sensing; Underwater structures
Geographical
Coverage
United States
TRIS Online
Accession No
769429
Contract Number DTFH61-C-00060
Report Number FHWA-RD-99-100
Resource type Tech Report
URL https://ntlrepository.blob.core.windows.net/lib/79000/79300/79328/009232.pdf
Format PDF
Database NTL Digital Repository