title: Railroad bridge instrumentation with fiber-optic sensors.
abstract: Fiber-optic sensors were installed on fatigue-critical components in the superstructure of a railroad bridge to monitor dynamic strains induced by trains crossing the bridge as well as to detect the onset of cracks. Each fiber Fabry-Perot interferometer (FFPI) strain gage was adhesively bonded to a stainless-steel strip to facilitate all-weather installation on the steel bridge members by spot welding. FFPI strain sensors were also installed on a rail at an approach to the bridge. Electrical resistive strain gages were colocated with the fiber-optic sensors on the bridge for the purpose of performance verification. In addition to the strain gages, fiber-optic continuity sensors for crack detection were bonded to the structure at critical locations. A telemetry system for transmitting the data over telephone lines was also installed at the bridge site. Dynamic response of the fiber-optic strain sensors is comparable with that of the electrical gages, and their performance has not degraded in the year since the initial installation.
authors.affiliation: Electrical Engineering Department, Texas A & M University, College Station, Texas 77843, USA.
authors.forename: W
authors.initials: W
authors.lastname: Lee
authors.forename: J
authors.initials: J
authors.lastname: Lee
authors.forename: C
authors.initials: C
authors.lastname: Henderson
authors.forename: H F
authors.initials: HF
authors.lastname: Taylor
authors.forename: R
authors.initials: R
authors.lastname: James
authors.forename: C E
authors.initials: CE
authors.lastname: Lee
authors.forename: V
authors.initials: V
authors.lastname: Swenson
authors.forename: R A
authors.initials: RA
authors.lastname: Atkins
authors.forename: W G
authors.initials: WG
authors.lastname: Gemeiner