The effect of damage due to particle debonding on the constitutive response of highly filled composites is investigated using two multiscale homogenization schemes: one based on a closed-form micromechanics solution, and the other on the finite element implementation of the mathematical theory of homogenization. In both cases, the particle debonding process is modeled using a bilinear cohesive ...

A shear-lag analysis based on energy is used to predict the amount of debonding that occurs when a fiber fragment breaks into two fragments. The shear-lag analysis reproduces all features of more sophisticated analyses. A drawback of the shear-lag analysis, however, is that it depends on an unknown parameter which can be expressed in terms of an effective fiber volume fraction. If the effective...

The debonding of Pressure Sensitive Adhesives (PSA) is a classical example of the difficult and unsolved issue of fracture in soft viscoelastic confined materials. The presence of a complex debonding region where the adhesive undergoes cavitation and the very large strain of a spontaneously formed fibrillar network has defied many modeling attempts over the past 70 years. We present here a nove...

This research program is intended to verify the influence of using distributed external U-wrap CFRP anchorage to shift the failure mode from overall debonding to sectional flexural failure for concrete beams externally bonded with CFRP sheets. Premature cover delamination and FRP debonding are predominant failure modes in FRP flexural strengthening that may be delayed or prevented by using FRP ...

Accurate measurement of interfacial properties is critical any time two materials are bonded--in composites, tooth crowns, or when biomaterials are attached to the human body. Yet, in spite of this importance, reliable methods to measure interfacial properties between dissimilar materials remain elusive. Here we present an experimental approach to quantify the interfacial fracture energy Γi tha...

in this paper, a systematic study on the effects of particle size and hybrid of two different size of silica nanoparticles on the toughening mechanisms of bisphenol-a epoxy was conducted. nanosilica particles with mean diameter of 17 nm and 65 nm were blended into epoxy system. probable synergy effects of these two nanoparticles on young’s modulus and yield strength have been investigated. resu...

Damage evolution in heterogeneous solids is modeled using transformation field analysis and imperfect interface model. Stress changes caused by local debonding are simulated by residual stresses generated by equivalent transformation strains or eigenstrains. Decohesion and both overall and local stress and strain rates are derived from thermodynamics of irreversible processes, which provide an ...

This study focuses on the optimizing the microstructure to improve the efficiency for healing interfacial debonding in fiber-reinforced polymers (FRPs). Healing is accomplished by incorporating a microcapsulated healing agent and catalytic chemical trigger within a coating layer on the surface of the fiber strands. Self-healing is demonstrated on flat tensile specimens of unidirectional FRPs. T...

The potential challenge at the fag end of orthodontic treatment is to restore the tooth structure as was prior to the beginning of the treatment. The aim of the article is to give a proper insight into the methodology of debonding not only from the orthodontist’s point of view but also keeping in mind the general practitioners who follow the procedure. At times, cases which are very well treate...