We present numerical simulations of the fall of a two dimensional (2D) model granular material in a rectangular container and study the decompactionof this granular assembly consisting of non-cohesive particles. During the fall we observe the occurrence of cracks splitting the initial pile into pieces. Cracks preferentially occur in the lower part of the array, an eeect also observed experiment...

* Corresponding author; Email: [email protected] ABSTRACT An important task in mixed-mode fracture analysis and prediction is the simulation of crack growth under mixed-mode conditions. To complete such a task, one must have (a) a computer code capable of handling the kinematics of general crack growth and determining the stress and deformation states during crack growth, and (b) a fracture crit...

We have considered the problem of elastic wave velocities in a matrix containing aligned ellipsoidal fluid-filled cracks. This problem is relevant o a variety of geophysical pplications, including crustal and mantle seismology and the behavior of stressed and dilatant rock. When the cracks are ellipsoids of revolution, the composite is transversely isotropic and is describable with five elastic...

A image processing algorithm was developed for detecting stress cracks in corn kernels using a commercial vision system. White light in back-lighting mode with black-coated background having a small aperture for the light provided the best viewing conditions. The kernel images, when processed using the algorithm developed, produced white streaks corresponding to the stress cracks. Double stress...

This paper investigates the efficiency of Ultrasonic Pulse Velocity (UPV) method in detecting cracks and flaws inside the concrete. A series of concrete beams and slab specimens were cast and damaged to simulate the different mechanisms possible in a reinforced concrete deck due to mechanical loading. Two types of simulated cracks, namely, cracks perpendicular and cracks parallel to axis of bea...

The problem of N cracks interaction in an isotropic elastic solid is decomposed into a subproblem of a homogeneous solid without crack and N subproblems with each having a single crack subjected to unknown tractions on the two crack faces. The unknown tractions, namely pseudo tractions on each crack are expanded into polynomials with unknown coefficients, which have to be determined by the cons...

Denda and Marante [1] have developed the boundary element method for the mixed mode fracture analysis of multiple curvilinear cracks in the general anisotropic solids in two dimensions for which in-plane Mode I, II, and out-of-plane Mode III, of fracture are coupled. They have developed the crack tip singular element (CTSE) to model any curvilinear cracks, including center and edge cracks. The ...

An advanced boundary element method (BEM) with thin-body capabilities was developed recently for the study of interphases in ®ber-reinforced composite materials (Y.J. Liu, N. Xu and J.F. Luo, Modeling of interphases in ®berreinforced composites under transverse loading using the boundary element method, ASME J. Appl. Mech. 67 (2000) 41±49). In this BEM approach, the interphases are modeled as t...

Article Info ABSTRACT Article history: Received Oct 17, 2016 Revised Dec 4, 2016 Accepted Feb 2, 2017 Nondestructive assessment of cracks in metallic parts has always been a topic of industrial interest. In the past, different approaches have been proposed to assess such cracks. Recently, semi-orthogonal compactly supported spline wavelets were utilized to efficiently identify the 3D spatial lo...

In order to have fault identification for the gate rotor shaft with multiple cracks effectively, the quantity identification method of the gate rotor shaft with multiple cracks based on wavelet finite element method is established and the frequency test of the gate rotor shaft based on blind source separation algorithm is analyzed. Firstly the wavelet finite element was established by combining...