The Sheepbed mudstone, Yellowknife Bay formation, Gale crater, represents an ancient lakebed now exhumed and exposed on the Martian surface. The mudstone has four diagenetic textures, including a suite of early diagenetic nodules, hollow nodules, and raised ridges and later diagenetic light-toned veins that crosscut those features. In this study, we describe the distribution and characteristics...

When cracks form in a thin contracting layer, they sequentially break the layer into smaller and smaller pieces. A rectilinear crack pattern encodes information about the order of crack formation, as later cracks tend to intersect with earlier cracks at right angles. In a hexagonal pattern, in contrast, the angles between all cracks at a vertex are near 120 degrees. Hexagonal crack patterns are...

A FGM layer sandwiched between two isotropic layers weakened by several interface cracks under antiplane loading is studied. This paper examines the modelling of cracks by distribution of strain nuclei along crack lines. In this investigation, the Volterra-type screw dislocation employed between FGM and an elastic layer. To solve the dislocation problem, the complex Fourier transform is applied...

A FGM layer sandwiched between two isotropic layers weakened by several interface cracks under antiplane loading is studied. This paper examines the modelling of cracks by distribution of strain nuclei along crack lines. In this investigation, the Volterra-type screw dislocation employed between FGM and an elastic layer. To solve the dislocation problem, the complex Fourier transform is applied...

The mesoscopic concept is a way to deal with complex materials with an internal structure within continuum mechanics. It consists of extending the domain of the balance equations by mesoscopic variables and of introducing a local distribution function of these variables as a statistical element. In our case microcracks are modelled as penny shaped and completely characterized by their diameter ...

This paper contains a theoretical formulation of multiple interface cracks in two bonded dissimilar half planes subjected to in-plane traction. The distributed dislocation technique is used to construct integral equations for a dissimilar mediums weakened by several interface cracks. These equations are of Cauchy singular type at the location of dislocation, which are solved numerically to obta...

In order to study the fracture propagation behavior after interaction between hydraulic fractures and natural fractures, cohensive unit of Abaqus finite element software is used simulate influence in rock on fractures. The simulation results show that when approach angle kept constant, as in-situ stress difference increases, are more likely penetrate expand along direction maximum horizontal pr...

Cracks emerge due to various forces or stresses. After discerning the cracks preferably by non-destructive techniques, there is a need to find the reason for their appearance. With very exact analysis of the shape, form and dimension of the cracks and their location on the structural elements, we can deduce the reason for their formation.  This makes, proposing a suitable solution for preventin...

Cracks emerge due to various forces or stresses. After discerning the cracks preferably by non-destructive techniques, there is a need to find the reason for their appearance. With very exact analysis of the shape, form and dimension of the cracks and their location on the structural elements, we can deduce the reason for their formation. This makes, proposing a suitable solution for preventing...

The role of grain bridging in affecting the initial rising portion of the R-curve and the transient, non-steady-state behavior of short cracks during (cyclic) fatigue-crack propagation has been quantitatively examined in a 99.5% pure alumina. Fatigue-crack growth properties for both long and short ( af < 2 mm) cracks emanating from machined notches (root radius, 15–150 m) were investigated, whe...