Most fiber optic sensors are point sensors that can measure the strain only at a local point of a beam, although strain distribution is non-uniform along the length of a beam. Long gage fiber optic sensors that measure integrated strain over a relatively long length can consider strain variation. This type of sensor was found to be efficient and useful for monitoring large-scale structures. On the other hand, the maximum strain in a beam cannot be measured with long gage optic sensors; the safety of a steel beam is analyzed by a comparison between the maximum stress measured during monitoring and the allowable stress of the beam calculated by a design code. Therefore, in this paper, simple mathematical models are presented for the determination of the maximum values of strains or stresses in a beam based on the average strains measured by long gage optic sensors. The model was tested in an experiment by comparing the maximum strain directly obtained from electrical gages and the calculated maximum strain from long gage optic sensors.
Bibliographical noteFunding Information:
The work presented in this paper was supported by research fund of the National Research Laboratory program (Project no. 2005-01504) from the Ministry of Science and Technology in Korea.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Metals and Alloys
- Electrical and Electronic Engineering