Coupling Boundary Element Reliability Algorithms applied to Probabilistic Analysis of Crack Propagation in Structures subject to Fatigue

An efficient boundary element procedure for the dynamic analysis of crack propagation in unbounded and arbitrary shape finite bodies is presented. The procedure is based on the direct time domain formulation of the boundary element method. A moving singular element and a remeshing technique have been developed to model the asymptotic solution of the stresses near the propagating crack tip. These ideas are easily implemented for a boundary discretization as opposed to similar procedures previously developed in a finite element context. The method is applied to problems of dynamic crack propagation in finite and infinite elastic domains. The obtained numerical results are compared with infinite domain analytical solutions and with available numerical solutions for finite domains.

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Two-Dimensional Fracture Mechanics Analysis Using a Single-Domain Boundary Element Method

Mathematical Problems in Engineering ◽

10.1155/2012/581493 ◽

2012 ◽

Vol 2012 ◽

pp. 1-26 ◽

Cited By ~ 1

Author(s):

Chien-Chung Ke ◽

Cheng-Lung Kuo ◽

Shih-Meng Hsu ◽

Shang-Chia Liu ◽

Chao-Shi Chen

Keyword(s):

Boundary Element Method ◽

Crack Propagation ◽

Boundary Element ◽

Domain Boundary ◽

Circumferential Stress ◽

Single Domain ◽

Propagation Path ◽

Two Dimensional ◽

Anisotropic Rock ◽

Element Method

This work calculates the stress intensity factors (SIFs) at the crack tips, predicts the crack initiation angles, and simulates the crack propagation path in the two-dimensional cracked anisotropic materials using the single-domain boundary element method (BEM) combined with maximum circumferential stress criterion. The BEM formulation, based on the relative displacements of the crack tip, is used to determine the mixed-mode SIFs and simulate the crack propagation behavior. Numerical examples of the application of the formulation for different crack inclination angles, crack lengths, degree of material anisotropy, and crack types are presented. Furthermore, the propagation path in Cracked Straight Through Brazilian Disc (CSTBD) specimen is numerically predicted and the results of numerical and experimental data compared with the actual laboratory observations. Good agreement is found between the two approaches. The proposed BEM formulation is therefore suitable to simulate the process of crack propagation. Additionally, the anisotropic rock slope failure initiated by the tensile crack can also be analyzed by the proposed crack propagation simulation technique.

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Development of Efficient Crack Growth Simulator Based on Hot-Mix Asphalt Fracture Mechanics

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1832-13 ◽

2003 ◽

Vol 1832 (1) ◽

pp. 105-112 ◽

Cited By ~ 11

Author(s):

Boonchai Sangpetngam ◽

Bjorn Birgisson ◽

Reynaldo Roque

Keyword(s):

Fracture Mechanics ◽

Crack Propagation ◽

Boundary Element ◽

Crack Growth ◽

Hot Mix Asphalt ◽

Displacement Discontinuity ◽

Successful Implementation ◽

Loading Conditions ◽

Premature Failure ◽

Major Mode

It has long been accepted that cracking of hot-mix asphalt (HMA) pavements is a major mode of premature failure. Many state departments of transportation have verified that pavement cracking occurred not only in fatigue cracking in which a crack initiates from the bottom of the asphalt layer but also in other modes such as low-temperature cracking and the more recently identified top-down cracking. Recent work at the University of Florida has led to the development of a crack growth law based on viscoelastic fracture mechanics that is capable of fully describing both initiation and propagation of cracks in asphalt mixtures. The model requires the determination of only four fundamental mixture parameters, which can be obtained from less than 1 h of testing using the Superpave® indirect tensile test (IDT). These parameters can account for microdamage, crack propagation, and healing for stated loading conditions, temperatures, and rest periods. The generalization of the HMA crack growth law needed for its successful implementation into a displacement discontinuity boundary element method is described. The resulting HMA boundary element approach is shown to predict the crack propagation of two coarse-graded mixtures under cyclic IDT loading conditions.

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