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Comparative Study of Strain Measurement Techniques for Assessing Creep in CFRP Tendons
Alexandra Boloux1,2, Iurii Burda2, Luke A Bisby1
1Institute of Infrastructure and Environment, University of Edinburgh, Edinburgh EH93JL, UK.
Sensors (Basel, Switzerland)
|November 27, 2025
Summary
Accurately measuring creep strain in Carbon Fibre-Reinforced Polymer (CFRP) tendons is crucial for bridge design. This study highlights how experimental artifacts significantly distort strain sensor data, necessitating careful validation.
Area of Science:
- Materials Science
- Civil Engineering
- Polymer Science
Background:
- Epoxy matrices in CFRP tendons exhibit viscoelastic behavior, leading to creep strains.
- Accurate creep strain quantification is vital for refining conservative bridge design guidelines.
Purpose of the Study:
- To investigate creep behavior in CFRP tendons under sustained tensile loading.
- To evaluate the influence of experimental artifacts on various strain sensing techniques used in CFRP creep testing.
Main Methods:
- CFRP tendons were subjected to sustained tensile loads (80% and 88% UTS).
- Four strain sensing techniques were employed: foil strain gauges, contact extensometer, Digital Image Correlation (DIC), and distributed fiber optic sensing (DFOS).
- Experimental artifacts like rig movement, temperature, and surface inhomogeneities were analyzed.
Main Results:
- Significant measurement distortions were observed across different sensors.
- The extensometer showed a 250% strain increase due to tendon slip.
- DFOS detected localized strain peaks 150% higher than the surface average.
Conclusions:
- Sensor-induced noise can substantially contaminate creep strain data in CFRP.
- Rigorous experimental protocols and thorough sensor validation are critical for accurate CFRP creep studies.
Keywords:
CFRP tendonscreep straindigital image correlation (DIC)extensometersfiber optic strain sensingfoil strain gaugesMore Related Videos
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