Title:
Numerical Analysis of RC Beams Strengthened with SRG
Author(s):
Massimo Petracca, Guido Camata, Christian Carloni, Annalisa Napoli, Roberto Realfonzo, Paolo Casadei
Publication:
Symposium Paper
Volume:
324
Issue:
Appears on pages(s):
6.1-6.12
Keywords:
experimental tests, finite element, flexural strengthening, grout, RC slabs.
DOI:
10.14359/51702358
Date:
4/1/2018
Abstract:
The use of Fiber Reinforced Polymer (FRP) strengthening systems for reinforced concrete (RC) members represents nowadays an effective alternative to traditional strengthening techniques. Recently, a new class of composites have emerged known as Steel Reinforced Grout (SRG), consisting of steel fibers embedded in an inorganic matrix and applied by using manual techniques and traditional handcraft.
An experimental campaign was recently carried out that aims at assessing the performance and effectiveness of SRG
strengthening systems to improve the flexural behavior of RC slabs. The present work uses the experimental results to validate the numerical prediction of a FEM code, developed by the authors, to analyze the flexural behavior of SRG-strengthened slabs.
The cross-sectional response is obtained using a fiber-model equipped with a plasticity model for rebars, a continuumdamage
model for SRG, and a plastic-damage model for concrete.
Overall, the numerical predictions are in good agreement with the experimental results. The model reproduces with
acceptable accuracy the nonlinear behavior of the tested strengthened beams, as well as the failure point both in terms
of failure modes and ultimate strength and displacement. In some cases, slight differences can be found between the
numerical and experimental results. These differences are discussed in this work.
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