Use of a Ground-Penetrating Radar System to Detect Pre- and Post-Flood Scour atSelected Bridge Sites in New Hampshire, 1996-98

摘要

Ground-penetrating radar was used to measure the depth and extent of existing andinfilled scour holes and previous scour surfaces at seven bridges in New Hampshire from April 1996 to November 1998. Ground-penetrating-radar survey techniques initially were used by the U.S. Geological Survey to study streambed scour at 30 bridges. Sixteen of the 30 bridges were resurveyed where floods exceeded a 2-year recurrence interval. A 300-megahertz signal was used in the ground-penetrating radar system that penetrated through depths as great as 20 feet of water and as great as 32 feet of streambed materials.