Jai Hak Park^*

Digital Engineering and Digital Twin, Vol.2, pp. 79-101, 2024, DOI:10.32604/dedt.2024.047280

Abstract A finite element alternating method has been known as a very convenient and accurate method to solve two and three-dimensional crack problems. In this method, a general crack problem is solved by a superposition of two solutions. One is a finite element solution for a finite body without a crack, and the other is an analytical solution for a crack in an infinite body. Since a crack is not considered in a finite element model, generating a model is very simple. The method is especially very convenient for a fatigue crack growth simulation. Over the past 40 years, S. N.… More >

Huizhen Liu^1,2, Duanying Wan³, Meng Wang³, Zheming Zhu³, Liyun Yang^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.1, pp. 349-368, 2024, DOI:10.32604/cmes.2023.028197

Abstract Stress waves affect the stress field at the crack tip and dominate the dynamic crack propagation. Therefore, evaluating the influence of blasting stress waves on the crack propagation behavior and the mechanical characteristics of crack propagation is of great significance for engineering blasting. In this study, ANSYS/LS-DYNA was used for blasting numerical simulation, in which the propagation characteristics of blasting stress waves and stress field distribution at the crack tip were closely observed. Moreover, ABAQUS was applied for simulating the crack propagation path and calculating dynamic stress intensity factors (DSIFs). The universal function was calculated by the fractal method. The… More >

Abdullah Alsit^*, Mohammad Alkhedher, Hasan Hamdan

CMC-Computers, Materials & Continua, Vol.73, No.3, pp. 5315-5329, 2022, DOI:10.32604/cmc.2022.031042

Abstract Stress Corrosion Cracking (SCC) process through which cracks occur in a variety of susceptible materials is a result of a combination of residual or applied stresses and corrosion. In oil and gas field, buried pipeline steels are made of low-alloy steels with a ferritic-pearlitic structure, such as X70. In dilute solutions, these materials are prone to SCC failure. The Near-neutral simulated soil solution (NS4) solution is established to imitate SCC conditions and subsequently became the industry requirement for crack growth experiments in the majority of laboratories. The strain-assisted active crack pathways are considered while modelling SCC growth as an oxide… More >

Shuangxin He¹, Chaoyang Wang¹, Xuan Zhou^1,*, Leiting Dong^1,*, Satya N. Atluri²

CMES-Computer Modeling in Engineering & Sciences, Vol.131, No.3, pp. 1857-1882, 2022, DOI:10.32604/cmes.2022.019160

Abstract The Symmetric Galerkin Boundary Element Method is advantageous for the linear elastic fracture and crackgrowth analysis of solid structures, because only boundary and crack-surface elements are needed. However, for engineering structures subjected to body forces such as rotational inertia and gravitational loads, additional domain integral terms in the Galerkin boundary integral equation will necessitate meshing of the interior of the domain. In this study, weakly-singular SGBEM for fracture analysis of three-dimensional structures considering rotational inertia and gravitational forces are developed. By using divergence theorem or alternatively the radial integration method, the domain integral terms caused by body forces are transformed… More >

Dennis Bäcker¹, Andreas Ricoeur², Meinhard Kuna¹

Structural Durability & Health Monitoring, Vol.7, No.1&2, pp. 1-22, 2011, DOI:10.3970/sdhm.2011.007.001

Abstract A new sensor concept for monitoring fatigue crack growth in technical structures is presented. It allows the in-situ determination of the position of the crack tip as well as the fracture mechanical quantities. The required data are obtained from a piezoelectric polymer film, which is attached to the surface of the monitored structure. The stress intensity factors and the crack tip position are calculated from electrical potentials obtained from a sensor array by solving the non-linear inverse problem. More >

A.V. Ekhlakov², O.M. Khay², Ch. Zhang², J. Sladek³, V. Sladek³

Structural Durability & Health Monitoring, Vol.6, No.3&4, pp. 329-350, 2010, DOI:10.3970/sdhm.2010.006.329

Abstract In this paper, transient crack analysis in two-dimensional, isotropic, continuously non-homo -ge -neous and linear elastic functionally graded materials is presented. A boundary-domain element method based on boundary-domain integral representations is developed. The Laplace-transform technique is utilized to eliminate the dependence on time. Laplace-transformed fundamental solutions of linear coupled thermoelasticity for isotropic, homogeneous and linear elastic solids are applied to derive boundary-domain integral equations. The numerical implementation is performed by using a collocation method for the spatial discretization. The time-dependent numerical solutions are obtained by the Stehfest's inversion algorithm. For an edge crack in a finite domain under thermal shock,… More >

R. Afshar¹, F. Berto^1,2

Structural Durability & Health Monitoring, Vol.9, No.4, pp. 349-364, 2013, DOI:10.32604/sdhm.2013.009.349

Abstract Using the finite element method, three-dimensional models of a number of periodic blunt and sharp notches subjected to tension loading are carried out. The aim of this research is to investigate the thickness effect on the location of maximum stress and notch stress intensity factor (NSIF) of corresponding blunt and sharp periodic notches respectively. With this aim, a wide range of notch geometries are examined. While for two-dimensional plates weakened by periodic notches some results are available in the literature, this paper first faces with the problem of three-dimensional cases. The total of about 100 geometrical configurations are investigated.
It… More >

R. Afshar¹, F. Berto¹

Structural Durability & Health Monitoring, Vol.9, No.2, pp. 167-180, 2013, DOI:10.32604/sdhm.2013.009.167

Abstract In this study, the main advantages of the strain energy density (SED) approach and some recent applications of the SED to the fatigue analysis of welded joints are reviewed. In addition, the paper investigates the scale effect in the threaded plates with sharp notches subjected to tension loading. Some closed form expressions for evaluation of the notch stress intensity factors (NSIFs) of periodic sharp notches, obtained by SED approach, are employed. The new expressions are applicable to narrow notches when the ratio between the notch depth and the plate width, t/W, is lower than 0.025 providing very accurate results. The… More >

P.H. Wen¹, M.H. Aliabadi²

Structural Durability & Health Monitoring, Vol.8, No.3, pp. 223-248, 2012, DOI:10.32604/sdhm.2012.008.223

Abstract A mesh-free method for modelling crack growth in functionally graded materials is presented. Based on the variational principle of the potential energy, mesh-free method has been implemented with enriched radial bases interpolation functions to evaluate mixed-mode stress intensity factors, which are introduced to capture the singularity of stress at the crack tip. Paris law and the maximum principle stress criterion are adopted for defining the growth rate and direction of the fatigue crack growth respectively. The accuracy of the proposed method is assessed by comparison to other available solutions. More >

G. Meneghetti¹

Structural Durability & Health Monitoring, Vol.8, No.2, pp. 111-130, 2012, DOI:10.3970/sdhm.2012.008.111

Abstract This paper deals with the local approach based on the Notch Stress Intensity Factors (NSIFs) to analyse the fatigue behavior of welded joints. In transverse load carrying fillet-welded joints, failure may occur either at the toe or at the root, depending on the geometry. At the toe, due to the flank angles that are usually encountered in practice, mode I local stresses are singular, while mode II stresses are not. Conversely, at the root of the particular joints analysed in the present paper both mode I and mode II stresses are singular and must be taken into account in fatigue… More >