Improved Stresses Analysis of a Functionally Graded Beam under Prestressed CFRP Plate

Abstract

In this paper, a new analytical solution is presented to predict the interfacial stresses of a functionally graded beam reinforced by a prestressed CFRP plate under thermo-mechanical load. A finite element (FE) analysis is also employed to validate the results of the analytical solution, the results from both models agreed very closely. Also, a parametric study is carried out in order to identify the effects of various material and geometrical properties on the magnitude of interfacial stresses. The presented results show that the interfacial stresses are highly concentrated at the end of the laminate, which can lead to a debonding at this location. Also, the material and geometrical properties have a significant impact on the magnitude of interfacial stresses. This new research approaches the practical reality of the structures in their environment by taking into consideration a combination of neglected terms by the other studies. Therefore, the results presented in this paper can serve as a benchmark for future analyses of functionally graded beams strengthened by prestressed Carbon fibre-reinforced polymer (CFRP) plates and improve the rehabilitation, mechanical and corrosion resistance.

New design for reducing interfacial stresses of reinforced structures with FRP plates

“…In addition, several possible failure modes at different places in the adhesive joint are more likely to occur in case of steel beams. A low-order analysis can be used to predict the interfacial stress in the bond, such as the work of Wu et al (1997), Jones et al (1988), Saadatmanesh and Malek (1998), Triantafillou and Antonopoulos (2000), Ascione and Feo (2000), Smith and Teng (2001), Yang et al (2004), Deng (2004), Tounsi and Benyoucef (2007), Stratford and Cadei (2006), Edalati and Irani (2012), Bensaid et al (2013), Kerboua et al (2013), Ghafoori (2013), Brairi et al (2018), developing different theories of predicting the interfacial stresses in the adhesive layer of a bonded structure with FRP plates. On the other hand, many other researchers have been focusing on reducing the interfacial stresses by either altering the physical properties of the materials or enhancing the geometrical design of the structure.…”

Improved numerical analysis of structures reinforced by composite FRP: Hygrothermal and prestressing loads with taper effect

“…In addition, there are several works to evaluate the couple (FRP-steel) and (FRP-concrete), which were experimentally investigated under the shear tensile and combined loading, such as Jiang et al, 17 Jiang et al, 18 Mendes et al, 19 Lin et al, 20 and Jones et al, 21 the different experimental bonding studies give appreciable results. In recent applications, the use of prestressed laminates has been developed in several laboratories with tests on different materials and on various structures, such as Nordin, 22 Bassetti, 23 Luke, 24 and De Lorenzis et al 25 This technique of prestressing laminates can be exploited well, which gives a more effective strengthening, according to Benachour et al 26 The problem of interfacial shear and normal stresses when prestressed laminates are used has treated by Benachour et al, 26 Al-Emrani and Kliger, 27 and Brairi et al 28 This original research aims to study the debonding phenomenon using an analytical model and a numerical finite element model, developed under ABAQUS software version 6.145 to identify the interfacial stresses of a steel beam strengthened by prestressed FRP plates, taking into account a new approach of prestressing force and hygrothermal effect with taper model. The numerical and analytical results are compared with the results developed by Deng et al, 10 This model gave a good agreement with those obtained by the experimental results done by Jones et al 21 After verifying the accuracy of the present work, a parametric study is used to identify the effects of various geometrical and material properties on the magnitude of stresses concentration.…”