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http://dx.doi.org/10.12989/csm.2021.10.4.299

Fiber reinforced polymer in civil engineering: Shear lag effect on damaged RC cantilever beams bonded by prestressed plate  

Abderezak, Rabahi (Civil Engineering Department, Laboratory of Geomatics and sustainable development, University of Tiaret)
Daouadji, Tahar Hassaine (Civil Engineering Department, Laboratory of Geomatics and sustainable development, University of Tiaret)
Rabia, Benferhat (Civil Engineering Department, Laboratory of Geomatics and sustainable development, University of Tiaret)
Publication Information
Coupled systems mechanics / v.10, no.4, 2021 , pp. 299-316 More about this Journal
Abstract
This paper presents a careful theoretical investigation into interfacialstressesin damaged RC cantilever beamwith bonded prestressedFRPcomposites,taking into accountloadingmodel,shearlag effect and theprestressed compositesimpact.These composites areused,in particular,forrehabilitationofstructuresby stoppingthepropagation of the cracks. They improve rigidity and resistance, and prolong their lifespan. In this paper, an original model is presented to predict and to determine the stresses concentration attheFRPend,with the newtheory analysis approach. This research gives more precision related to the others studies which neglect the effect of prestressed composites coupled with the applied loads. A parametric study has been conducted to investigate the sensitivity of interface behaviorto parameterssuch aslaminate and adhesive stiffness, the thickness ofthe laminate and the fiber orientations where allwere found to have amarked effect on themagnitude ofmaximumshear and normalstressin the composite member. The numerical resolution was finalized by taking into account the physical and geometric properties of materialsthat may play an important role in reducing the stress values. Thisresearch is helpful for the understanding on mechanical behaviour ofthe interface and design ofthe FRP-damagedRChybrid structures.
Keywords
interfacial stresses; prestressed composite; RC cantilever beam; shear lag effect; strengthening;
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