OBJECTIVE To determine whether there is a difference on the bone architecture in patients with femoral neck fracture compared to patients with intertrochanteric fractures and assess the importance of aging on bone microarchitecture in patients with proximal femoral fracture. METHODS Biopsy of the iliac crest was made in seventeen patients between 55 and 90 years old who were admitted to the e...

A BPNN approach is developed to invert the fracture parameters from Thomsen parameters. A BPNN is trained by pairs of fracture parameters and Thomsen parameters which are calculated by a complex relationship. After training, the BPNN can emulate the inverted relationship between them and then to invert fracture parameters from Thomsen parameters. The results are encouraging. This BPNN approach ...

Accepting the Beremin approach to the analysis of cleavage failure criteria the local fracture parameters have been calculated using FEM for Charpy type specimen. Two types, of model fenitic microstructures have been selected for presentation differing by carbide thickness and scatter of fracture toughness data. For the microstructures investigated the Weibull stresses (location parameters) wer...

This contributions outlines the main features of the cohesive cracks as they were conceived by Hillerborg: as a ~onstitutive model able to describe the generation of a progressively fracturing surface and its evolution up to complete failure. After outlining the basic hypotheses, the numerical tools available for structural analysis are examined, including the simplest approximations reducing t...

in this paper, a finite element model is developed for the fully hydro-mechanical analysis of hydraulic fracturing in partially saturated porous media. the model is derived from the framework of generalized biot theory. the fracture propagation is governed by a cohesive fracture model. the flow within the fracture zone is modeled by the lubrication equation. the displacement of solid phase, and...

assessment of the correlation between rock brittleness and rock fracture toughness has been the subject of extensive research works in the recent years. unfortunately, the brittleness measurement methods have not yet been standardized, and rock fracture toughness cannot be estimated satisfactorily by the proposed indices. in the present study, statistical analyses are performed on some data col...

Following our innovative experimental spontaneous fracture models for frictional fractures (compression and shear) and mixed-mode fractures (tension and shear) in identical materials, we designed a laboratory model to investigate the effects of material contrast on mixed-mode spontaneous fracture along a bimate-rial interface. A series of interesting phenomena are observed, including asymmetry ...

The single point incremental forming (SPIF) is one of the dieless forming processes which is widely used in the sheet metal forming. The correct selection of the SPIF parameters influences the formability and quality of the product. In the present study, the Gurson-Tvergaard Needleman (GTN) damage model was used for the fracture prediction in the numerical simulation of the SPIF process of alum...