A numerical technique for modeling fatigue crack propagation of multiple coplanar cracks is presented. The proposed method couples the extended finite element method (X-FEM) [Int. J. Numer. Meth. Engng. 48 (11) (2000) 1549] to the fast marching method (FMM) [Level Set Methods & Fast Marching Methods: Evolving Interfaces in Computational Geometry, Fluid Mechanics, Computer Vision, and Materials ...

Dynamic crack propagation in elastomer membranes is investigated; the focus laid on cracks reaching speed of shear waves material. The specific experimental setup developed to measure presented details. protocol consists (1) stretching an membrane under planar tension loading conditions, then (2) initiating a small one side membrane. measured all along path both reference and actual configurati...

The mechanical behaviour of Earth’s curst with a self-similar structure of faults is modelled using a continuous sequence of continua each with its own size of the averaging volume element. The overall tensorial properties scale isotropically, i.e. according to a power law with common exponent. In fault systems modelled by sets of 2-D cracks, the scaling is isotropic for both isotropically orie...

The corrosion fatigue crack growth characteristics of small (>35pm) surface and corner cracks in aluminum alloy 7075 is established. The early stage of crack growth is studied by performing in situ long focal length microscope (500X) crack length measurements in laboratory air and 1% NaCl environments. To quantify the “small crack effect” in the corrosive environment, the corrosion fatigue crac...

We present a Finite Element model, which is devoted to describing the failure mechanics of quasi-brittle materials (e.g. concrete), such as stiffness recovery effect at transition from tension compression, and cyclic behavior with low number cycles. The material studied meso-scale, thus considered heterogeneous medium. model formulated within framework strong discontinuity analysis implemented ...

This paper deals with a procedure to calculate the elastic stress intensity factors for arbitrary-shaped cracks in plane stress and plane strain problems. An assumed displacement.hybrid finite element model is employed wherein the unknowns in the final algebraic system of equations are the nodal displacements and the elastic stress intensity factors. Special elements, which contain proper singu...

We first present a nonuniform box search algorithm with length of each side of the square box dependent on the local smoothing length, and show that it can save up to 70% CPU time as compared to the uniform box search algorithm. This is especially relevant for transient problems in which, if we enlarge the sides of boxes, we can apply the search algorithm fewer times during the solution process...

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...

This paper reports the simulation of phased array ultrasonic wave propagation using Finite Difference Time Domain (FDTD) method to image crack like defects in Aluminum Blocks and Stainless Steel elbow sections. Inclined crack like defects have been considered for the simulation. Experiments were also performed on an Aluminum block with inclined embedded cracks various sizes in order to validate...