This article discusses results obtained from a parametric study to analytically evaluate the impingement of a crack at the interface of an environmental barrier coating (EBC) and a monolithic Silicon nitride (Si 3 N 4) layered ceramics substrate. The study establishes a correlation that leads to determine if the crack is arrested or advanced by either penetrating or deflecting along the EBC/sub...

Compressive failure by splitting is studied herein via an analytical model. The use of a shear lag model to determine the stress state at the crack tip and the modeling of the region away from the crack tip by the 3D elasticity equations leads to a simple analytical expression is used to determine the compliance changes for both unsteady crack growth as well as steady state crack growth under c...

The work involves develops attended by a numerical execution of the eXtend Finite Element Method premises a measurement by the fracture process cracked so many cracked plates an application will be processed for the calculation of the stress intensity factor SIF. In the first we give in statically part the distribution of stress, displacement field and strain of composite plate in two cases unc...

OBJECTIVE to investigate the seroprevalence of hepatitis C in crack users in Piauí. METHOD seroepidemiological survey, undertaken in the Psycho-Social Care Centers for Drugs and Alcohol (CAPS AD) in Piauí in the period December 2011 to May 2012. A questionnaire was administered and blood samples were collected for serological research. Fisher's exact test and the Mann-Whitney test were used, ...

The properties of slow crack growth in brittle materials are analyzed both theoretically and experimentally. We propose a model based on a thermally activated rupture process. Considering a 2D spring network submitted to an external load and to thermal noise, we show that a preexisting crack in the network may slowly grow because of stress fluctuations. An analytical solution is found for the e...

We consider an elastic plate of infinite length and constant width supported simply along its two parallel edges and having a finite length crack along its centreline. In particular, we look for and find trapped modes (localised oscillations) in the presence of the crack. An explicit wide-spacing approximation based on the Wiener-Hopf technique applied to incident wave scattering by semi-infini...

The boundary effect model (BEM) for concrete fracture and the effects of specimens size and crack length has previously been criticized on theoretical grounds, but the experimental evidence found in the literature, when taken alone, has been too limited to judge the validity of BEM conclusively. New, separately published, comprehensive fracture experiments, which were made on specimens cast fro...

The propagation of (planar) cracks in a heterogeneous brittle material characterized by a random field of toughness is considered, taking into account explicitly the effect of the crack front roughness on the local stress intensity factor. In the socalled strong-pinning regime, the onset of crack propagation appears to map onto a second-order phase transition characterized by universal critical...

Occurrence of top down and bottom up fatigue cracking in asphaltic pavements is common. Conventional pavement analysis methods ignore the existence of cracks in asphaltic layers. However, it seems that the responses of cracked pavement would not be the same as a pavement without crack. This paper describes effects of crack type, position and length, and vehicles tire inflation pressure and axle...

safety and failure in gas pipelines are very important in gas and petroleum industry. for this reason, it is important to study the effect of different parameters in order to reach the maximum safety in design and application. in this paper, a three dimensional finite element analysis is carried out to study the effect of crack length, crack depth, crack position, internal pressure and pipe thi...