A thorough examination of the quasi-static penetration of a floating elastic-brittle plate via a fracture mechanics approach has been presented by Bažant and Kim. Bažant and Kim reach the conclusion that there is a size effect (in terms of the plate thickness, h). A few of the assumptions made by these authors will be examined in this discussion. The formulation presented by Bažant and Kim assu...

Modeling of stress corrosion cracking (SCC) is performed using the combination of the finite element method and the symmetric Galerkin boundary element method. The uncracked structural component is represented with finite elements. The crack is simulated using the boundary element method. The superposition principle is employed for combining two solutions. The equilibrium state for the system o...

This paper presents a new method for continuum based shape sensitivity analysis for a crack in a homogeneous , isotropic, and linear-elastic body subject to mixed-mode (modes I and II) loading conditions. The method is based on the material derivative concept of continuum mechanics, domain integral representation of an interaction integral, and direct differentiation. Unlike virtual crack exten...

We study general mathematical framework for variation of potential energy with respect to domain deformation. It enables rigorous derivation of the integral formulas for the energy release rate in crack problems. Applying a technique of the shape sensitivity analysis, we formulate the shape derivative of potential energy as a variational problem with a parameter. Key tools of our abstract theor...

To improve resolution of in-situ measurement crack closure and opening in fatigue, potential drop (PD) technique has been further developed to measure thousands times through each load cycle with high precision. The results are interpreted physical phenomena like strain, Poisson’s effect, piezo-resistivity, plasticity, growth. Application the fatigue growth tests on aluminum 2024-T3 CCT specime...

A nominally at penny-shaped crack is subjected to a static loading. A perturbation method is developed for calculating the stress-intensity factors, based on an asymptotic analysis of the governing hypersingular boundary integral equation for the crack-opening displacement. Comparisons with known exact solutions for an inclined at elliptical crack and for a crack in the shape of a spherical cap...

There has been a renewed interest of late in the mechanisms responsible for the in ̄uence of the load ratio, R, and the maximum stress intensity, Kmax, on the threshold for fatigue-crack growth, DKth. While mechanistic explanations in the past have largely focused on the role of crack closure, it is certainly not the only mechanism by which Kmax in ̄uences DKth. In this work, we examine the e€ect...

The plane strain problem of determining strain energy release rate, crack energy, and crack-opening displacement (COD) for a moving Griffith crack at the interface of two dissimilar orthotropic half-planes is considered. The problem is reduced to a pair of singular integral equations of second kind which have finally been solved by using Jacobi polynomials. Graphical plots of the strain energy ...

Cracking in Silicon solar cells is an important factor for the electrical power-loss of photovoltaic modules. Simple geometrical criteria identifying the amount of inactive cell areas depending on the position of cracks with respect to the main electric conductors have been proposed in the literature to predict worst case scenarios. Here we present an experimental study based on the electrolumi...