Title:
Distributed Sensing for Shrinkage and Tension-Stiffening Measurement
Author(s):
Matthew B. Davis, Neil A. Hoult, Sanchit Bajaj, and Evan C. Bentz
Publication:
Structural Journal
Volume:
114
Issue:
3
Appears on pages(s):
753-764
Keywords:
bond; fiber-optic strain sensors; reinforced concrete; shrinkage; tension stiffening
DOI:
10.14359/51689463
Date:
5/1/2017
Abstract:
A series of reinforcing bar and reinforced concrete specimens were instrumented with fiber-optic cables to measure distributed strain profiles along the specimens. The strain due to shrinkage was measured at 3, 7, 21, and 28 days in three specimens to determine the shrinkage strain profile. Reinforcement and reinforced concrete specimens were tested in axial tension and the distributed strain measurements enabled the tension-stiffening effect in the reinforced concrete members to be quantified. Due to variations in the development of cracks, measurements on both sides of the reinforcing bar were required to obtain the average strain behavior. The shrinkage strain measurements were also critical in terms of calculating the effect of tension stiffening. The average distributed strain measurements were compared to a proposed tension stiffening model and overall good agreement was seen, although the cracking load was often overestimated by the model.
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