Strengthening of steel structures with fiber-reinforced polymer composites

A review of finite element analysis of adhesively bonded joints

Both environmental and economic factors have driven the development of recycling routes for the increasing amount of composite waste generated. This paper presents a new paradigm to fully recycle epoxy-based carbon fiber reinforced polymer (CFRP) composites. After immersing the composite in ethylene glycol (EG) and increasing the temperature, the epoxy matrix can be dissolved as the EG molecules participate in bond exchange reactions (BERs) within the covalent adaptable network (CAN), effectively breaking the long polymer chains into small segments. The clean carbon fibers can be then reclaimed with the same dimensions and mechanical properties as those of fresh ones. Both the dissolution rate and the minimum amount of EG required to fully dissolve the CAN are experimentally determined. Further heating the dissolved solution leads to repolymerization of the epoxy matrix, so a new generation of composite can be fabricated by using the recycled fiber and epoxy; in this way a closed-loop near 100% recycling paradigm is realized. In addition, epoxy composites with surface damage are shown to be fully repaired. Both the recycled and the repaired composites exhibit the same level of mechanical properties as fresh materials.

Carbon Fiber Reinforced Thermoset Composite with Near 100% Recyclability

An Introduction to Composite Materials: Fabrication

Probabilistic Physics of Failure-based framework for fatigue life prediction of aircraft gas turbine discs under uncertainty

Computation of the stress intensity factors for repaired cracks with bonded composite patch in mode I and mixed mode

Fatigue life prediction under variable loading based on a new damage model

This paper presents a free vibration analysis of functionally graded materials nano-plate resting on Winkler–Pasternak elastic foundations based on two-variable refined plate theories including the porosities effect. The small-scale effects are introduced using the nonlocal elasticity theory with a new shear deformation function. The governing equations are obtained through the Hamilton’s principle. The effect of material property, porosities, various boundary conditions and elastic foundation stiffnesses on free vibration functionally graded materials nanoplate are also presented and discussed in detail. The present solutions are compared with those obtained by other researchers. The results are in a good agreement with those in the literature.

Free vibration analysis of FGM nanoplate with porosities resting on Winkler Pasternak elastic foundations based on two-variable refined plate theories

Comparison of double and single bonded repairs to symmetric composite structures: a numerical analysis

In this study, the three-dimensional finite element method is used to analyze the effects of the patch shape on the efficiency end the durability of bonded composite repairs of aircraft structures. The stress intensity factor at the crack tip is used as fracture criteria. The determination of this factor allows us to estimate the repair efficiency. The analysis of the stresses distribution in the adhesive layer allows us to estimate the durability of the adhesion between the damaged plate and the composite patch. The obtained results show that the repair performances are closely related to the patch shape. It was demonstrated that the rectangular shape of the patch could be improved using an “H” shape of the patch. This last shape could also be improved using an arrow shape.

B. Bachir Bouiadjra

Papers

Computation of the stress intensity factors for repaired cracks with bonded composite patch in mode I and mixed mode

Fatigue life prediction under variable loading based on a new damage model

Free vibration analysis of FGM nanoplate with porosities resting on Winkler Pasternak elastic foundations based on two-variable refined plate theories

Comparison of double and single bonded repairs to symmetric composite structures: a numerical analysis

Numerical analysis of the patch shape effects on the performances of bonded composite repair in aircraft structures