In-situ monitoring of Sungsan Bridge in Han River with an optical fiber sensor system

ABSTRACT Intnnsic Fabry—Perot optical fiber sensors were attached to a steel girder of theSungsan Bridge which is one of the longest span bridges in Han River in Seoul, Korea. The tests were performed as parts of satety diagnosis of the bridge. Weperformed the visual inspection first, then we chose three spans for System Identification of the bridge. We applied numbers of strain gauges, acceleration sensors and a deflection gauge as well as optical fiber sensors. Static and dynamic loads were applied to the bridge with 30 ton weigh tnicks. The optical fiber sensor system showed good responses to the static and dynamic loading with a resolution of approximately O.l2ii strain. In conclusion, the optical fiber sensors can he used as elements of bridge monitoring system. 1. INTRODLJCTONSungsan Bridge in Seoul, is one of the busiest motorway bridge in Korea carrying 190,000 vehicles per day. This study is performed as parts of safetydiagnosis of this bridge, and it is a first time in our country to apply Fabry—Perot optical fiber sensors to a bridge.In our country, there has been no examples of the application of optical fibersensors to real bridge. Optical fiber sensors having advantages of no electroma—