introduction: the restoration of endodontically treated teeth is a topic that has been studied extensively but it is still a challenge for dental practitioners. the aim of this study was to evaluate fracture resistance, fracture patterns and fracture location of endodontically treated human maxillary premolars restored with direct and indirect composite resin and ceramic restoration. methods: e...

An interaction integral method for evaluating mixed-mode stress intensity factors (SIFs) for two dimensional crack problems using NURBS-based isogeometric analysis method is investigated. The interaction integral method is based on the path independent J-integral. By introducing a known auxiliary field solution, the mixed-mode SIFs are calculated simultaneously. Among features of B-spline basis...

Fracture mode of ductile solids can vary depending on the history of stress state the material experienced. For example, ductile plates under remote in-plane loading are often found to rupture in mode I or mixed mode I/III. The distinct crack patterns are observed in many different metals and alloys, but until now the underlying physical principles, though highly debated, remain unresolved. Her...

A nonlinear elastic foundation model has been developed to predict the mixed-mode (modes I and II) delamination failure of laminated composites. Two types of nonlinear elastic foundations were used to represent pure mode I and pure mode II components of the material failure ahead of the crack tip. One is a tension spring foundation for mode I component and the other is a shear spring foundation...

The majority of fracture mechanics studies on the toughness of bone have been performed under tensile loading. However, it has recently been shown that the toughness of human cortical bone in the transverse (breaking) orientation is actually much lower in shear (mode II) than in tension (mode I); a fact that is physiologically relevant as in vivo bone is invariably loaded multiaxially. Since bo...

Natural and artificial materials including rocks and cement-based materials such as concrete and cement mortar are affected both physically and chemically by various natural factors known as weathering factors. The freeze-thaw process, as a weathering factor, considerably affects the properties of rocks and concrete. Therefore, the effect of the freeze-thaw process on the physical and mechanica...

Cohesive-zone models for interfaces incorporate both strength and energy parameters. Therefore, they provide a natural bridge between strength-based models and energy-based models for fracture, allowing delamination to be described by a single framework that covers a range of applications for which the strength or energy criteria alone might not be sufficient. In this paper, the relationships b...