von Mises yield criterion

About: von Mises yield criterion is a research topic. Over the lifetime, 4374 publications have been published within this topic receiving 82642 citations. The topic is also known as: Von Mises stress.

Numerical simulation of the convergence of a bolt‐supported tunnel through a homogenization method

Abstract: The present paper describes the numerical implementation of constitutive relationships previously developed for modelling the elastoplastic behaviour of bolted rockmass regarded as a homogenized anisotropic medium on the macroscopic scale. Attention is more particulary focused on the iterative algorithm involved in such a numerical method, which makes use of projection formulas onto the yield surface. Those formulas are made explicit in the case of a purely cohesive rock material obeying a von Mises yield condition with associated flow rule. Combined with a finite element code, the proposed numerical procedure is then carried out for simulating the advancement of a bolt-supported tunnel and calculating its convergence as the excavation proceeds. The results of this numerical simulation prove to agree perfectly well with those derived from an analytical model, thus validating the proposed numerical scheme. A quantitative study, varying some relevant parameters of the problem (bolt density, length of bolts, delay of placement behind the tunnel facing), is finally undertaken. It points to the versatility of the numerical approach, whose range of applicability can be further extended to various kinds of geotechnical structures reinforced by regularly distributed inclusions.

Mixed method and convex optimization for limit analysis of homogeneous Gurson materials: a kinematical approach

Abstract: A fully kinematical, mixed finite element approach based on a recent interior point method for convex optimization is proposed to solve the limit analysis problem involving homogeneous Gurson materials. It uses continuous or discontinuous quadratic velocity fields as virtual variables, with no hypothesis on a stress field. Its modus operandi is deduced from the Karush-Kuhn-Tucker optimality conditions of the mathematical problem, providing an example of cross-fertilization between mechanics and mathematical programming. This method is used to solve two classical problems for the von Mises plasticity criterion as a test case, and for the Gurson criterion for which analytical solutions do not exist. Using only the original plasticity criterion as material data, the method proposed appears robust and efficient. providing very tight bounds on the limit loadings investigated. (C) 2008 Elsevier Masson SAS. All rights reserved.

Three-dimensional evaluation of different prosthesis retention systems using finite element analysis and the Von Mises stress test.

Abstract: Background The aim of this paper is to underline the prosthodontics components features of two different overdenture retention systems on dental implants. The use of titanium, dental implants for replacing missing teeth is today considered to be a predictable procedure giving the patients esthetic and function for long time. Methods Finite element analysis (FEA) and tests based on the Von Mises criterion have been applied in order to evaluate the stress distribution over two different prosthodontics retention systems. Two models with the ball attachment and with the Locator® systems have been created and put on simulated chewing stresses. Results The two systems were subjected to axial and oblique forces and both guaranteed good results over simulated masticatory cycle. However, the Locator system seemed to better respond to the overall load distributions. Conclusions Clinicians should choose the better prosthetic solution for the ridge they want to restore. Both retention systems offer long-term success if applied following the manufacture guide limitations and suggestions.