A new approach for analyzing cracked problems in 2D orthotropic materials using the well-known element free Galerkin method and orthotropic enrichment functions is proposed. The element free Galerkin method is a meshfree method which enables discontinuous problems to be modeled efficiently. In this study, element free Galerkin is extrinsically enriched by the recently developed crack-tip orthot...

In this work, the mechanism for fracture of brittle substances such as rocks under a uniform normal tension is considered. The oriented straight micro-cracks are mostly created in all the polycrystalline materials resulting from the stress concentrations. The present work focuses on the interactions of the pre-existing micro-cracks, which can grow and propagate within a rock-like specimen. The ...

Abstract A pre-existing plane of weakness along the fault is comprised a particular pattern joints dipping at different orientations. The stress state, partially defined by orientation fault, determines potential slip failure and hence evolution permeability. Here influence on permeability was investigated direct fluid injection inside with three sets orientations (45°, 60° 110°), through coupl...

This letter reports a multiplexed optical displacement sensor using a thin core fiber (TCF) exciter. The TCF exciter is followed by a stripped single mode optical fiber. A small section of buffer is used as the movable component along the single mode fiber. Ultra-weak cladding mode reflection (< - 75 dB) was employed to probe the refractive index discontinuity between the air and buffer coating...

We introduce the notion of time continuity for the analysis of cohesive zone interface finite element models. We focus on “initially rigid” models in which an interface is inactive until the traction across it reaches a critical level. We argue that methods in this class are time discontinuous, unless special provision is made for the opposite. Time discontinuity leads to pitfalls in numerical ...

A boundary element method (BEM) combined with a linear slip boundary condition is proposed to calculate SH wave scattering from fractures. The linear slip boundary condition was proposed by Schoenberg (1980) to model elastic wave propagation through an imperfectly bonded interface, where the traction cross the interface is continuous and displacement is discontinuous. Here, we demonstrate how t...

AIM Analysis of indications for stapes revision surgery in patients qualified for the secondary procedure at the Otosurgery Dept. Medical University of Lodz. MATERIAL AND METHODS 25 cases of stapes revision surgery out of the 385 total treated surgically otosclerosis cases are discussed. RESULTS In group A (patients after total stapedectomy) the following indications for the secondary surgi...

In a recent paper Elvin and Leung [1] demonstrated the advantages of a new fast boundary element algorithm for solving closed crack problems. This algorithm uses the Displacement Discontinuity Method (DDM) and subdivides the problem into two sub-problems, one for the outer boundaries of the structure and one for the crack. In common with most methods for crack problems, it uses interface-or joi...

Localized deformation such as shear bands, compaction bands, dilation bands, combined shear/compaction or shear/dilation bands, fractures, and joint slippage are commonly found in rocks. Thus, modeling their inception, development and propagation, and effect on stress response is important with regard to making informed engineering design decisions involving these materials. Following a GulfRoc...