An evolutionary approach for fatigue crack detection in cantilever type of machine structure is investigated in this paper. Fault like fatigue crack detection has received a great attention in recent years. A surface transverse open edge crack is considered for this study. Actual fatigue crack may behave like a non-linear due to opening and closing under vibration. But due to small level of vib...

The investigation of the effects of cracks or similar weaknesses on the load carrying capacity of structural elements such as columns, beams and shells is an important problem in civil, mechanical, earthquake and aerospace engineering. In this paper, adaptive neuro-fuzzy inference system (ANFIS) and artificial neural network (ANN)model have been successfully used for the buckling analysis of sl...

Crack tip deformations and fracture parameters in functionally graded glass-filled epoxy beams are experimentally evaluated under static and dynamic loading conditions. Beams with unidirectional, monotonic elastic gradients and cracks along the gradient are examined. SEN samples with increasing or decreasing Young’s modulus ahead of the crack tip are studied in symmetric four-point bending and ...

In this paper, the general plane problem for an infinite strip containing multiple cracks perpendicular to its boundaries is considered. The problem is reduced to a system of singular integral equations. Two specific problems of practical interest are then studied in detail. The first is the investigation of the interaction effect of multiple edge cracks in a plate or beam under tension or bend...

We examine the fracture mechanics of tearing graphene. We present a molecular dynamics simulation of the propagation of cracks in clamped, free-standing graphene as a function of the out-of-plane force. The geometry is motivated by experimental configurations that expose graphene sheets to out-of-plane forces, such as back-gate voltage. We establish the geometry and basic energetics of failure ...

This paper reviews the capabilities of a plasticity-induced crack-closure model to predict fatigue lives of metallic materials using “small-crack theory” for various materials and loading conditions. Crack tip constraint factors, to account for three-dimensional stateof-stress effects, were selected to correlate large-crack growth rate data as a function of the effective-stress-intensity factor...

We have carried out systematic fracture experiments in a single edge notch geometry over a range of stretch rates on dual crosslink hydrogels made from polyvinyl alcohol chains chemically crosslinked with glutaraldehyde and physically crosslinked with borate ions. If the energy release rate necessary for crack propagation was calculated conventionally, by using the work done to deform the sampl...

AbstracbThe results of an experimental investigation of thermally induced parallel edge cracks in a half-plane consisting of brittle material are reported. A free edge of a glass plate heated to a uniform temperature, was brought in contact with a liquid bath cooled by dry ice. The thermal contraction of the boundary layer produced interacting tension cracks. When no initial cracks existed, a l...

A new approach was developed for the evaluation of energy release rate by the virtual crack closure technique in quadratic and linear elements. The generalized method allows arbitrary placement of the side nodes for quadratic elements and thus includes both standard elements, with mid-side nodes, and singularity elements, with quarter-point nodes, as special cases of one general equation. It al...