An assessment of the plasticity-induced crack-closure concept is made, in light of some of the questions that have been raised on the validity of the concept, and the assumptions that have been made concerning crack-tip damage below the crack-opening stress. The impact of using other crack-tip parameters, such as the cyclic crack-tip displacement, to model crack-growth rate behavior was studied...

Direct Displacement-Based Design (DDBD) is a performence-based seismic design method that has been proposed and well developed over the past two decades to design RC frame structures, shear walls and bridges. In this method, the behavior of a multi-degree-of-freedom (MDOF) sysytem is approximaeted by an equivalent single-degree-of-freedom (SDOF) substitute structure. Although this method has be...

in a large scale cyclic storage system ,as the number of rule parameters and/or number of operating period increase, general purpose gradient-based nlp solvers and/or genetic algorithms may loose their merits in finding optimally feasible solution to the problem. in these cases hybrid ga which decomposes the main problem into two manageable sub-problems with an iterative scheme between ga and l...

Brain plasticity, the ability of the nervous system to encode experience, is a modulatory process leading to long-lasting structural and functional changes. Salient experiences induce plastic changes in neurons of the hippocampus, the basis of memory formation and recall. In the suprachiasmatic nucleus (SCN), the central circadian (~24-h) clock, experience with light at night induces changes in...

This work demonstrates numerically how microplasticity, i.e. the yielding behavior below conventional 0.2% plastic strain threshold, can lead to initiation of cracks at subsurface defects, in rolling contact applications operating under realistic loads. A 3D elasto-plastic finite element model is employed perform shakedown analysis bearing steel around a small spherical void with two different ...

This work investigates plastic deformation around non-metallic inclusions in rolling contact fatigue applications. Subsurface stresses from Hertzian theory are applied form of far-field loading on an elasto-plastic micro-mechanical model isolated inclusion. Initial and cyclic micro-scale plasticity quantified, assuming linear kinematic hardening for the steel matrix elastic or perfectly behavio...