BACKGROUND AND PURPOSE There have been few prospective studies examining young and middle-aged patients with hip fracture. We therefore investigated background data, risk factors, and the trauma mechanism in young and middle-aged patients with femoral neck fracture. PATIENTS AND METHODS 185 patients, 27 young (20-49 years old) and 158 middle-aged (50-69 years old) were prospectively included ...

This letter describes a newly discovered phenomenon: ductile fracture in cementitious materials. The brittle nature of materials such as concrete and ceramics has prompted the development of various approaches to enhance their fracture toughness. Fibre reinforcement has been the common focus in the toughening of the brittle materials. Two types of fracture have been observed to date in cementit...

BACKGROUND Changes in patient-reported outcomes like health related quality of life (HRQOL) and global quality of life (GQOL) in patients with low-energy distal radius fracture might be related to fracture, or be within the normal range of variation in an elderly population. Hence, the present study aims to examine: Whether patients with low-energy distal radius fracture attain their pre-fractu...

_______________________________________________________________________________________ A fracture mechanics approach has been used to investigate how the addition of high-temperature resistant thermoplastic modifiers can increase the fracture energy, Gc, of brittle cyanate-ester polymers. Tests were performed using adhesive joint specimens at -55, 21 and 150°C. The fracture energies of poly(et...

By partitioning the total stresses in a damaged composite into either mechanical and residual stresses or into initial and perturbation stresses, it was possible to derive two exact results for the energy release rate due to crack growth. These general results automatically include the effects of residual stresses, tractionloaded cracks, and imperfect interfaces. These effects are normally not ...

This paper mainly reports an experimental investigation on the residual mechanical and fracture properties of polystyrene aggregate concrete (PAC) after exposure to high temperatures up to 800 degrees Celsius. The fracture properties namely, the critical stress intensity factor ( K I C S ), the critical crack tip opening displacement (CTODC) for the Two-Parameter Model, and the fracture energy ...

Dental structures capture, retain and fragment food for ingestion. Gnathostome dentition should be viewed in the context of the prey's material properties. Animal muscle and skin are mechanically tough materials that resist fragmentation unless energy is continually supplied directly to the tip of the fracture by some device such as a blade edge. Despite the variety of bladed tooth morphologies...

Influence of different microstructure of La-based fully amorphous samples and its composites on the impact fracture energy were investigated and discussed. Results showed improvement in fracture energy of glassy metals with the presence intermetallic phases, but deteriorated in the presence of dendrite phases and high volume % of crystalline phases.

Measurements of the mechanical properties of snow are essential for improving our understanding and the prediction of snow failure and hence avalanche release. We performed fracture mechanical experiments in which a crack was initiated by a saw in a weak snow layer underlying cohesive snow slab layers. Using particle tracking velocimetry (PTV), the displacement field of the slab was determined ...

The aim of this paper is to fabricate micro-gears via laser shock punching with Spitlight 2000 Nd-YAG Laser, and to discuss effects of process parameters namely laser energy, soft punch properties and blank-holder on the quality of micro-gears deeply. Results show that dimensional accuracy is the best shocked at 1690 mJ. Tensile fracture instead of shear fracture is the main fracture mode under...