Yi Shi^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.29, No.2, pp. 1-1, 2024, DOI:10.32604/icces.2024.012366

Abstract The Nickel-based superalloy is wieldy applied in hot components of aero turbine engine due to its superior mechanical property at elevated temperature. However, the working condition of engine hot components are severe and thus the effect of high temperature, oxidation and time-dependent loading on fatigue crack growth behavior should be considered in structure analysis. In this study, first the effect of environment was experimentally investigated. Stand compact tension (CT) specimens under different temperatures and loading frequencies were tests to evaluate the role of temperature and time-dependent effect on fatigue crack growth. Results show that if… More >

Qiuyi Wang¹, Rong Yang¹, Bo Chen², Rui Bao^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.29, No.1, pp. 1-1, 2024, DOI:10.32604/icces.2024.011878

Abstract Effects of hold time on the fatigue crack growth behavior in electron-beam powder-bed-fusion (PBF-EB) Inconel 718 alloy at 650 ∘C have been investigated in this study, with focuses on the anisotropic fatigue cracking resistance and fracture mechanism. The V-type specimen (which loading parallel to the columnar grain boundaries) gives better dwell-fatigue cracking resistance to the H-type specimen (which loading perpendicular to the columnar grain boundaries) due to its large deflections (nearly 90 °) on the crack path. These deflections are related to the change of crack growth mechanism. In both V-type and H-type specimens, when More >

Binchao Liu^1,2,*, Qiuyi Wang², Rui Bao²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.29, No.1, pp. 1-1, 2024, DOI:10.32604/icces.2024.011835

Abstract With the everlasting pursuit for weight reduction, efforts are devoted to applying additively manufactured (AM) structures in aeronautic vehicles; however, anomalous fatigue crack growth (FCG) behaviors, such as deflection and branching, are recently observed in macroscale, which deviates from the predictions by classic fracture mechanics. In this work, FCG behaviors of direct energy deposited (DED) Ti–5Al–5Mo–5V–1Cr–1Fe (TC18 in China) are investigated, in which fatigue crack deflections induced by combined impacts of loading and microstructures are revealed. Experiment results show that cracks are more deflected in columnar grains due to the preferred distribution of acicular a… More >

Xiaoli Wei¹, D. A. Makhloof^1,2, Xiaodan Ren^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.134, No.1, pp. 9-34, 2023, DOI:10.32604/cmes.2022.020160 - 24 August 2022

Abstract Fatigue failure phenomena of the concrete structures under long-term low amplitude loading have attracted more attention. Some structures, such as wind power towers, offshore platforms, and high-speed railways, may resist millions of cycles loading during their intended lives. Over the past century, analytical methods for concrete fatigue are emerging. It is concluded that models for the concrete fatigue calculation can fall into four categories: the empirical model relying on fatigue tests, fatigue crack growth model in fracture mechanics, fatigue damage evolution model based on damage mechanics and advanced machine learning model. In this paper, a More >

Zhongmin Xiao¹, Wengang Zhang², Yanmei Zhang^{1, *}, Mu Fan³

CMC-Computers, Materials & Continua, Vol.62, No.1, pp. 267-280, 2020, DOI:10.32604/cmc.2020.06567

Abstract Fluctuated loadings from currents, waves and sea ground motions are observed on offshore steel pipelines, and they will result in small cracks to propagate continuously and cause unexpected damage to offshore/geotechnical infrastructures. In spite of the availability of efficient techniques and high-power computers for solving crack problems, investigations on the fatigue life of offshore pipelines with 3D interacting cracks are still rarely found in open literature. In the current study, systematic numerical investigations are performed on fatigue crack growth behaviours of offshore pipelines containing coplanar and non-coplanar cracks. Extended finite element method (XFEM) is adopted More >

Akiyuki Takahashi^1,*, Takaki Fujiwara¹, Yuichi Shintaku²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.4, pp. 170-170, 2019, DOI:10.32604/icces.2019.05151

Abstract This paper presents a Paris law-based cohesive zone model (CZM) for fatigue crack growth simulations to enable the consideration of the plasticity induced crack closure effect, which is known to be a source of substantial crack growth retardation. In order to avoid the addition of any redundant model parameters, the basic equation of the CZM is derived from the Paris law so that the CZM has only the parameters of Paris law. Thus, the parameters can be determined by referring the existing experimental data of the Paris law without any troublesome fitting processes. Only the More >

Jie Wang¹, Wei Jiang^1,*, Qi Wang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.118, No.2, pp. 377-395, 2019, DOI:10.31614/cmes.2019.01836

Abstract A elastic-plastic fatigue crack growth (FCG) finite element model was developed for predicting crack growth rate under cyclic load. The propagation criterion for this model was established based on plastically dissipated energy. The crack growth simulation under cyclic computation was implemented through the ABAQUS scripting interface. The predictions of this model are in good agreement with the results of crack propagation experiment of compact tension specimen made of 304 stainless steel. Based on the proposed model, the single peak overload retardation effect of elastic-plastic fatigue crack was analyzed. The results shows that the single peak More >

Salman A. Albinali¹, David R. Jacques²

Structural Durability & Health Monitoring, Vol.10, No.1, pp. 1-17, 2014, DOI:10.3970/sdhm.2014.010.001

Abstract An analytic approach to exploring the tradespace associated with Structural Health Monitoring (SHM) systems is presented. Modeling and simulation of the life cycle of a legacy aircraft and the expected operational and maintenance events that could occur is shown. A focus on the SHM system detection of a significant crack length and the possibility of False Alarm (FA), miss detection and mishap events is investigated. The modeling approach allows researchers to explore the tradespace associated with safe and critical crack lengths, sensor thresholds, scheduled maintenance intervals, falsely triggered maintenance actions, and mishaps due to missed… More >

Xiyong Huang¹, M. H. Aliabadi², Z. Sharif Khodaei³

CMES-Computer Modeling in Engineering & Sciences, Vol.102, No.4, pp. 291-330, 2014, DOI:10.3970/cmes.2014.102.291

Abstract In this paper, a stochastic dual boundary element formulation is presented for probabilistic analysis of fatigue crack growth. The method involves a direct differentiation approach for calculating boundary and fracture response derivatives with respect to random parameters. Total derivatives method is used to obtain the derivatives of fatigue parameters with respect to random parameters. First- Order Reliability Method (FORM) is applied to evaluate the most probable point (MPP). Opening mode fatigue crack growth problems are used as benchmarks to demonstrate the performance of the proposed method. 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 >