Objectives: To investigate and quantify fall height, surface depth, and surface impact attenuation as risk factors for arm fracture in children who fall from playground equipment. Design: Unmatched case control study. Setting: Five case hospitals and 78 randomly selected control schools. Participants: Children aged less than 13 years in Victoria, Australia who fell from school playground equipm...

OBJECTIVES To investigate and quantify fall height, surface depth, and surface impact attenuation as risk factors for arm fracture in children who fall from playground equipment. DESIGN Unmatched case control study. SETTING Five case hospitals and 78 randomly selected control schools. PARTICIPANTS Children aged less than 13 years in Victoria, Australia who fell from school playground equi...

in this article, failure and fracture mechanisms in an aluminum alloy (which has been used in diesel internal combustion engines), with and without ceramic thermal barrier coatings, have been investigated under isothermal and non-isothermal fatigue loadings. in this research, the base material is an aluminum-silicon-magnesium alloy and the thermal barrier coating includes a metallic bond coat l...

Turbine-generator shafts are often subjected to a complex transient torsional loading. Such transient torques may initiate and propagate a circumferential crack in the shafts. Mode III crack growth in turbo-generator shafts often results in a fracture surface morphology resembling a factory roof. The interaction of the mutual fracture surfaces results in a pressure and a frictional stress field...

Surface topography and defect structures associated with ballistic impact in a commercial 94 percent alumina ceramic armor are described. Fracture surfaces were examined by scanning electron microscopy, augmenting previous replication electron fractography studies. Direct transmission electron microscopy was employed in characterizing defect structures in extracted fracture fragments on replica...

Bone fracture is a health concern for those with aged bone and brittle bone diseases. Mouse bone is widely used as a model of human bone, especially to investigate preclinical treatment strategies. However, little is known about the mechanisms of mouse bone fracture and its similarities and differences from fracture in human bone. In this work we present a methodology to investigate the fractur...

Underground nuclear weapon testing produces radionuclide gases which may seep to the surface. Barometric pumping of gas through explosion-fractured rock is investigated using a new sequentially-coupled hydrodynamic rock damage/gas transport model. Fracture networks are produced for two rock types (granite and tuff) and three depths of burial. The fracture networks are integrated into a flow and...