This paper presents a methodology for assessing the confidence and the predictive capability of prognosis models, using the application of fatigue crack growth analysis. Structures with complicated geometry and multi-axial variable amplitude loading conditions are considered. Several models – finite element model, crack growth model, retardation model, surrogate model, etc. – are efficiently co...

Recent theoretical results on elastic-plastic planestrain crack growth an~ reviewed and experimental results for crack growth in a 4140 steel are discussed in terms of the theoretical concepts. The theory is based on a recent asymptotic analysis of crack surface opening and strain distributions at a quasistatically advancing crack tip in an ideally plastic solid. The analysis is incomplete in t...

* Corresponding author; Email: [email protected] ABSTRACT An important task in mixed-mode fracture analysis and prediction is the simulation of crack growth under mixed-mode conditions. To complete such a task, one must have (a) a computer code capable of handling the kinematics of general crack growth and determining the stress and deformation states during crack growth, and (b) a fracture crit...

This paper presents a methodology for conducting a 3-D static fracture analysis with applications to a gas turbine compressor blade. An open crack model is considered in the study and crack-tip driving parameters are estimated by using 3-D singular crack-tip elements in ANSYS . The static fracture analysis is verified with a special purpose fracture code (FRANC3D). Once the crack front is perfe...

Al~tract--The mechanics of fracture of a stably extending interface crack in polymeric adhesive bonds undergoing very large shear deformation is studied using a rate-del~ndent finite element analysis. Plane-strain and J2 plasticity conditions are considered. Based on recent experimental observations, it is assumed that the local engineering shear strain at a certain distance (i.e. for the polym...

Crack is one of the most typical damage types in engineering structures, and therefore is a research focus in the field of structural health monitoring (SHM). The monitoring and evaluation methods for crack-type damage are studied using a Lamb wave-based RAPID algorithm (Reconstruction Algorithm for the Probabilistic Inspection of Damage) in this study, which is based on a correlation analysis....

BACKGROUND The health risks of crack cocaine smoking in public settings have not been well described. We sought to identify factors associated with public crack smoking, and assess the potential for a supervised inhalation facility to reduce engagement in this behavior, in a setting planning to evaluate a medically supervised crack cocaine smoking facility. METHODS Data for this study were de...

in this paper, the interface crack of two non-homogenous functionally graded materials is studied. subsequently, with employing the displacement method for fracture of mixed-mode stress intensity factors, the continuous variation of material properties are calculated. in this investigation, the displacements are derived with employing of the functional graded material programming and analysis o...

Mixed-mode dynamic crack growth behavior in a compositionally graded particle filled polymer is studied experimentally and computationally. Beams with single edge cracks initially aligned in the direction of the compositional gradient and subjected to one-point eccentric impact loading are examined. Optical interferometry along with high-speed photography is used to measure surface deformations...

iranian crack is a new form of narcotic substance that has found widespread prevalence iniran in the past years. crack only nominally resembles crack cocaine as it is widely different inits clinical signs. thus the present study aims to quantify the chemical combination of this drug.the samples included 18 specimen of crack collected from different zones of tehran, iran.all specimens were in th...