Stress monitoring of tensioned bars with fiber optic sensor

K. S. Lau; K. H. Wong; Tommy H.T. Chan; S. K. Yeung

doi:10.1117/12.269820

20 March 1997 Stress monitoring of tensioned bars with fiber optic sensor

K. S. Lau, K. H. Wong, Tommy H.T. Chan, S. K. Yeung

Proceedings Volume 2921, International Conference on Experimental Mechanics: Advances and Applications; (1997) https://doi.org/10.1117/12.269820
Event: International Conference on Experimental Mechanics: Advances and Applications, 1996, Singapore, Singapore

Abstract

An interferometric fiber optic sensor is used to monitor the vibration of a bar under tension. An analytical formula is derived to relate the density. Young modulus and the physical dimensions of the bar to its frequency of vibration, which is measured through FFT of the monitored signal from the fiber optic sensor. Bars made up of homogeneous materials are tested for the validity of the method, which is then applied to composite materials. In the latter application, an optical fiber, which form an integral part of the sensor, can be embedded into the bar during its fabrication process. For materials of stable moduli, the sensor can be used to measure the tension of the bar. For materials with unstable moduli, during its curing process, the aging period or otherwise, the sensor can be used to monitor the change. The method can also be used as an alternative to measure the moduli of materials and is especially suitable for composite materials. Due to the complexity of a composite material, the modulus measured by this method reflects an average effect of the bulk, whereas a conventional tensile test depends more on localized weaknesses of the composite.

Citation Download Citation

K. S. Lau, K. H. Wong, Tommy H.T. Chan, and S. K. Yeung "Stress monitoring of tensioned bars with fiber optic sensor", Proc. SPIE 2921, International Conference on Experimental Mechanics: Advances and Applications, (20 March 1997); https://doi.org/10.1117/12.269820

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available