Experimental and numerical evaluation of composite repairs on wood beams damaged by cross-graining

Abstract

Keywords:Wood Composite Repair Cohesive zone models Finite element analysis a b s t r a c t An experimental and Finite Element study was performed on the bending behaviour of wood beams of the Pinus Pinaster species repaired with adhesively-bonded carbon-epoxy patches, after sustaining damage by cross-grain failure. This damage is characterized by crack growth at a small angle to the beams longitudinal axis, due to misalignment between the wood fibres and the beam axis. Cross-grain failure can occur in large-scale in a wood member when trees that have grown spirally or with a pronounced taper are cut for lumber. Three patch lengths were tested. The simulations include the possibility of cohesive fracture of the adhesive layer, failure within the wood beam in two propagation planes and patch interlaminar failure, by the use of cohesive zone modelling. The respective cohesive properties were estimated either by an inverse method or from the literature. The comparison with the tests allowed the validation of the proposed methodology, opening a good perspective for the reduction of costs in the design stages of these repairs due to extensive experimentation.

Finite element analysis of flexural strengthening of timber beams with Carbon Fibre-Reinforced Polymers

“…Several numerical works have investigated the performance of strengthened RT members using the Finite Element (FE) method [15][16][17][18][19][20][21]. Khelifa et al [15] developed a numerical procedure to simulate the flexural behaviour of CFRP-strengthened timber beams wherein the kinematic continuity was assumed between adhesive and wood.…”

Adherend thickness effect on the tensile fracture toughness of a structural adhesive using an optical data acquisition method

“…The tn-δn law for the test specimen followed in this section is presented in Fig. 11, together with a possible trapezoidal approximation, particularly suited to model CZM laws for ductile adhesives [43]. The pertinent parameters for this specimen were t n ¼ 25.1 MPa and δnc ¼ 0.0692 mm.…”

Modélisation du comportement non-linéaire des poteaux en bois renforcés par la fibre de carbone

“…Cette technique de renforcement, du fait de sa simplicité de mise en application, ne nécessitant sur le terrain que peu de travaux de réparation, a séduit très rapidement les acteurs de la construction bois et son développement aété accéléré. L'utilisation de cette nouvelle technique du renforcement des structures bois par CFRP est largement conseillée dans [1][2][3][4][5].…”