Modeling and prediction of short/long term mechanical behavior of FRP-strengthened slabs using innovative composite finite elements. (15th April 2023)

• Record Type: Journal Article
• Authors: Wu, Rui; Xu, Rongqiao; Wang, Guannan
• Is Part Of: Engineering structures. Volume 281(2023)
• Publication Date: 2023-04-15
• Subjects: FRP-strengthening -- Finite element method -- Composite plate element -- Interfacial shear stress -- Viscoelastic behavior; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2023.115727
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: Two innovative multilayer composite plate elements are proposed. Realization the modeling of substrate, adhesive layer and FRP sheet in one element. Ability to analyze irregular structures. Optimization of FRP tapering ends and strengthening forms. Meeting the challenge of time integration and complex meshing in existing FE models. Abstract: The analysis of plates or slabs strengthened with fiber reinforced polymer (FRP), especially when it comes to geometric irregularity and the time-varying characteristics of adhesive, presents multi-faceted simulation, modeling and computational challenges. In this paper, two new multilayer composite plate elements are proposed to model and analyze FRP-strengthened slabs, aiming at meeting these challenges with efficiency. The novelty relies on that the innovative elements realize the modeling of substrate, adhesive layer and FRP sheet in one "macroscopic" element rather than modeling each component by separate elements. One of them is capable of emulating geometric irregular structures while the other has better accuracy, and the flexible combination of them can be used to achieve accurate simulation and calculation of various strengthening systems. Another novelty is the extension of the study from elastic to viscoelastic by introducing an appropriate rheological interface and correspondence principle. The consistency with literature verifies the correctness of the proposed elements, subsequently, they were used to investigate the influence of the FRP tapering ends and strengthening forms on the reinforcement effectiveness. It is found that the proposed method is convenient to predict the short/long term mechanical behavior of FRP strengthened slabs with accuracy and computational efficiency, thus contributing to the design and optimization of the strengthening system.