Scour Inspection Using Ground Penetrating Radar

by William A. Horne, Harbour & Associates, Albany, United States,



Document Type: Proceeding Paper

Part of: Hydraulic Engineering

Abstract:

This paper examines the capabilities of Ground Penetrating Radar (GPR) for river bed scour inspection based on a study carried out by Clarkson University, Potsdam, New York in association with the New York State Thruway Authority (NYSTA). With funding provided by the New York State Science and Technology Foundation (NYSSTF), researches at Clarkson used GPR equipment to investigate a number of bridge piers and abutments with optimal water and soil conditions. The 300 Mhz antenna was most successful penetrating silty, granular material in less than two (2) meters of water. These bridges were part of a detailed scour inspection program scheduled by the NYSTA for 1990 and 1991 in which all Thruway bridges were analyzed for maximum scour potential and hydraulic adequacy (Horne, 1992). Clarkson's findings with GPR equipment were compared with actual results of the NYSTA's full scale geotechnical investigation. Soil boring information from the latter provided ground-truth measurements necessary for calculating the depths of scour holes and scour interfaces. More importantly, the soil samples were used to calibrate the natural material properties, such as density and gradation, with the radar wave travel time for penetrating different channel bottom layers. Comparing the recovered soil samples with both the color output of the radar equipment and the amplitude of the returning signal displayed on an oscilloscope verified the existing scour conditions.

Subject Headings: Scour | Radar | Soil properties | River and stream beds | Penetration tests | Inspection | Soil water | New York | United States

Services: Buy this book/Buy this article

 

Return to search