This paper presents a micromechanics-based elastoplastic damage model for quasi-brittle rocks in compression stress state. The plastic strain is considered to be related to frictional sliding along microcracks and inherently coupled with damage evolution. By following a homogenization procedure, we first determine the free energy for the matrix-cracks system. The thermodynamic force associated ...

in all engineering applications where solid surfaces slide on each other, friction plays an important role. it becomes even more important, particularly in metal forming processes where the two sliding materials are metallic. among forming processes, forging is an important process, because of improving material structure, mechanical properties and reducing production time. an inverse analysis ...

SD Moffatt, WS Parkhill. Unusual presentations of ulnar nerve paresthesia: Mycotic aneurysm and leprosy. Can J Plast Surg 1996;4(4):217-220. Ulnar nerve compression causing clinical symptoms is a common occurrence. There are numerous conditions that can cause compression. Recently two very interesting and unusual etiologies were seen at the Plastic Surgery service. Leprosy causing ulnar nerve c...

Experimental evidence is presented to show that significant rotations of brittle phase inclusions of a Fe-rich intermetallic phase occur during plastic deformation on an Al Mg Si base wrought aluminum alloy. The particle rotations are quantitatively characterized, for uniaxial tension, compression, torsion, and notch-tension test specimens strained to different strain levels. The particle rotat...

a new model is proposed for two-dimensional simulation of the concrete fracture in compression. the model generated by using the voronoi diagram method and with considering random shape and distribution of full graded aggregates at the mesoscopic level. the aggregates modeled by combining irregular polygons, which then is placed into the concrete with no intersection between them. by this new m...

Two-phase bimetal composites contain both grain boundaries and bi-phase interfaces between dissimilar crystals. In this work, we use a crystal plasticity finite element framework to explore the effects of grain boundary interactions on the plastic stability of bi-phase interfaces. We show that neighboring grain interactions do not significantly alter interface plastic stability during plane str...

Using numerical simulations, we study the dynamical evolution of particles interacting via competing long-range repulsion and short-range attraction in two dimensions. The particles are compressed using a time-dependent quasi-one dimensional trough potential that controls the local density, causing the system to undergo a series of structural phase transitions from a low density clump lattice t...

Through computer simulations, we show that plasticity in twinned copper nanopillars can be either reversible or irreversible depending on the applied stress state. Copper nanopillars, containing twinned crystals, are subjected to both compression and tension, and the ratio of the resolved shear ðrRÞ to the normal stress ðrN Þ, R, is adjusted through variation of the orientation of the twin boun...