The origin of fracture in epithelial cell sheets subject to stretch is commonly attributed to excess tension in the cells' cytoskeleton, in the plasma membrane, or in cell-cell contacts. Here, we demonstrate that for a variety of synthetic and physiological hydrogel substrates the formation of epithelial cracks is caused by tissue stretching independently of epithelial tension. We show that the...

A new particle-based method, the material point method (MPM), has recently been extended to handle explicit cracks in a new algorithm called CRAMP or “CRAcks with Material Points.” This new method has several advantages for numerical work on fracture. Compared to finite element analysis, CRAMP can handle cracks with similar algorithmic efficiency, but is better at handling crack surface contact...

In continuous casting, it is very important to predict and detect the internal cracks of billet in time for ensuring continuous production, improving product quality and reducing production costs. Clustering analysis (CA) method is adopted to do feature extraction and classification for on-site data, by which ladder parameter tables of processing parameters and defect grades of internal cracks ...

Aging aircraft may develop multiple-site damage (MSD) that can reduce the structural integrity of fuselage structures. The existence of small cracks emanating from adjacent rivet holes in a fuselage lap-splice joint is of major concern. Small collinear cracks greatly reduce the residual strength of a panel with a lead crack. Recent studies predicting the residual strength of flat and curvilinea...

We study the Dirichlet problem for the 2D Laplace equation in a domain bounded by smooth closed curves and smooth cracks. In the formulation of the problem, we do not require compatibility conditions for Dirichlet’s boundary data at the tips of the cracks. However, if boundary data satisfies the compatibility conditions at the tips of the cracks, then this is a particular case of our problem. T...

In order to investigate the methods to heal fatigue cracks in metals, tubular specimens of 1045 steel with axial and radial fatigue cracks were treated under the eddy current. The optical microscope was employed to examine the change of fatigue cracks of specimens before and after the eddy current treatment. The results show that the fatigue cracks along the axial direction of the specimen coul...

Homogeneous global wrinkling patterns such as labyrinths, herringbones, ripples and straight stripes can be widely observed in natural and artificial systems, but localized wrinkling patterns (not including buckle-driven delaminations, folds, ridges and creases) are seldom observed in experiments. Here we report on the spontaneous formation of highly ordered wrinkled stripes localized by cracks...

The stress intensity factor solution for embedded circular cracks, semicircular and part-circular surface cracks in plates, quartercircular corner cracks in rods, and semicircular surface cracks at a hole in a plate are evaluated using a finite element alternating method. This method of superposition employs the standard 20-noded solid element solution for the untracked solid, and the complete ...

© 2013 IBRACON This paper proposes an automatic method based on the computing vision, implemented in a mobile platform, to inspect cracks in masonry and concrete. The developed algorithm for image processing performs this task from images of the cracks evolution. The contribution of this paper is the development of a mobile tool with quick response aiming to assist technicians in periodic visit...

The propagation of cracks in three dimensions is analyzed by a meshless method. The cracks are modeled by a set of triangles that are added when the propagation occurs. Since the method is meshless, no remeshing of the domain is necessary during the propagation. To avoid using a large number of degrees of freedom, the stress singularity along the front of the cracks is taken into account by an ...