existence of cracks in industrial structures is one of the important causes of their failure, especially when they are subjected to important axial compressive forces that might lead to buckling. therefore, it must be considered in stress analysis and designing and loading of such structures. in this paper, the buckling and post-buckling behaviors of stainless-steel cracked plates under axial c...

The plane problem of a crack terminating at the interface of a bimaterial piezoelectl:ic, and loaded on its fa.ces, is treated. The emphasis is placed on how to transform this problem into a non-homogeneous Hilbert problem. To make the derivation tractable, the concept of the axial conjugate is introduced and related to the complex conjugate. The angle between the crack line and the interface m...

Space-variant blur occurs when imaging through volume turbulence over sufficiently large fields of view. Space-variant effects are particularly severe in horizontal-path imaging, slant-path (air-to-ground or ground-to-air) geometries, and ground-based imaging of low-elevation satellites or astronomical objects. In these geometries, the isoplanatic angle can be comparable to or even smaller than...

The study of vibration response of a turbine blade helps to detect the crack presence in the blade which alters its dynamic characteristics. The change is characterized by changes in the modal parameters associated with natural frequencies. In this paper, study of vibration response is made for turbine blade in the presence of a crack like defect. Turbine blade is initially assumed as a cantile...

river bank erosion can result in considerable riparian land loss and the delivery of large volumes of sediment to reaches downstream. consequently, the ability to predict the stability and failure geometry of eroding river banks is an important prerequisite for es-timating the rate of bank erosion and sediment yield associated with bank erosion. in this paper a new model capable of analyzing th...

Crack propagation in an isotropic 2d brittle material is widely viewed as the interplay between two separate criteria. Griffith’s cap on the energy release rate along the crack path decides when the crack propagates, while the Principle of Local Symmetry PLS decides how, that is, in which direction, that crack propagates. The PLS, which essentially predicts mode I propagation, cannot possibly h...

When a blunt cutting tool is forced through a thin elastic sheet that is held along its lateral boundaries, a strikingly regular wavy cut can be left behind, examples of which are presented in Fig. 1. The thin film is brittle, hence it undergoes negligible irreversible deformation besides fracture. For tools much wider than the film’s thickness, the crack tip follows a highly reproducible nonsi...

Abstract. The existence of crack evolutions based on critical points of the energy functional is proved, in the case of a cohesive zone model with prescribed crack path. It turns out that evolutions of this type satisfy a maximum stress criterion for the crack initiation. With an explicit example, it is shown that evolutions based on the absolute minimization of the energy functional do not enj...

The fatigue crack growth in a coarse-grained Fe-2 wt% Si alloy is investigated in considerable detail. At room temperature, the material is quasi-brittle and the failure mode is mixed cleavage. Under a mode-I cyclic loading, the crack can overcome the barrier effect of grain boundaries, which dominates the overall damage evolution. Associated with the geometrically necessary crack front branchi...