Analysis of the Acoustic Response of a Railroad Bridge

K. Koppenhoefer[1], S.Yushanov[1], and M.H. McKenna[2]

[1]AltaSim Technologies, LLC, Columbus, Ohio, USA
[2]U.S. Army Engineering Research and Development Center

Aging infrastructure requires frequent inspections to assess their structural integrity. However, the large amount of existing infrastructure, and the distance between these structures present significant challenges to inspectors. Acoustics-based technologies represent a simple, and relatively inexpensive, technique to monitor the integrity of a structure. To develop these techniques, designers must understand the frequencies and sound pressure levels that develop from a typical bridge structure. Infrasound is acoustic energy whose frequency is below that of human perception. Large infrastructure, such as bridges, emits such signals at their natural or driven frequencies of vibration, providing an indication of the structural condition.