Recent three-point bend tests of size effect on the strength of geometrically scaled sandwich beams of three types – with no notches, and with notches at the upper or lower skin–foam interface, which were previously evaluated using simplified sandwich beam theory and equivalent linear elastic fracture mechanics, are now reanalyzed more accurately by finite elements. Zero-thickness interface ele...

This is the second in a series of two papers generated from a study on probabilistic meshless analysis of cracks. In this paper, a stochastic meshless method is presented for probabilistic fracture-mechanics analysis of linear-elastic cracked structures. The method involves an element-free Galerkin method for calculating fracture response characteristics; statistical models of uncertainties in ...

Concrete is a so called quasibrittle material which, despite predominantly elastic material response, exhibits in tension loading a stable non-linear fracture response, when tested under displacement control. The reason for the non-linearity is the development of a fracture process zone, in front of the crack, due to micro-cracking and crack bridging. The effect of the fracture process zone is ...

this study investigates propagation of mode i crack in b70 pre-stressed concrete sleepers by fracture mechanics approach. a new experimental analysis is done for notched b70 pre-stressed concrete sleepers with replica test and image analysis. a scanning electron microscope test (sem) and an image analysis are applied for the replica test in order to determine crack length and crack mouth openin...

Mode II delamination toughness of z-pin reinforced composite laminates is investigated using finite element (FE) method. The z-pin pullout process is simulated by the deformation and breakage of non-linear springs. A critical shear stress criterion based on linear elastic fracture mechanics is used to simulate crack growth in an end-notched-flexure (ENF) beam made of z-pinned laminates. The mod...

We study atomistically the fracture of single-crystal silicon at atomically sharp notches with opening angles of 0° ~a crack!, 70.53°, 90° and 125.3°. Such notches occur in silicon that has been formed by etching into microelectromechanical structures and tend to be the initiation sites for failure by fracture of these structures. Analogous to the stress intensity factor of traditional linear e...

The present work aims at investigating the failure size effect of a spheroidal void in an infinite linear elastic solid under remote tension by means coupled Finite Fracture Mechanics (FFM) approach. opening stress field and intensity factor (SIF) annular crack surrounding cavity —necessary for FFM implementation— are obtained numerically through parametric axisymmetric finite element analyses ...

This paper deals with the construction of tip asymptotes for a hydraulic fracture deflating in permeable elastic medium. Specifically, describes changing nature asymptotic fields during arrest and recession phases following propagation after fluid injection has ended. It shows that as deflates phase, region dominance linear mechanics asymptote $w\sim x^{1/2}$ aperture $w$ distance $x$ from fron...

The surface of a quenched and tempered spring steel may have decarburized layer from which the carbon component has been reduced. fatigue strength is low compared to base metal, can easily develop cracks. Recently, failure was reported in tension clamp (SKL 15) DFF-300 rail fastening system during use on one urban transit route South Korea. As result measuring depth SKL 15 where occurred, thinn...