Anastasios P. Vassilopoulos
École Polytechnique Fédérale de Lausanne
Composite numberUltimate tensile strengthGlass transitionEngineeringFinite element methodComposite laminatesComposite materialEpoxyGlass fiberMaterials scienceStiffnessStrain energy release rateFracture (geology)PolymerPultrusionFracture mechanicsStructural engineeringAdhesiveFibre-reinforced plasticStress (mechanics)
174Publications
28H-index
2,360Citations
Publications 169
Newest
#1Anastasios P. Vassilopoulos (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 28
#2Efstratios F. Georgopoulos (AHLEI: American Hotel & Lodging Educational Institute)H-Index: 10
Abstract Novel computational methods such as artificial neural networks, adaptive neuro-fuzzy inference systems and genetic programming are used in this chapter for the modeling of the nonlinear behavior of composite laminates subjected to constant amplitude loading. The examined computational methods are stochastic nonlinear regression tools, and can therefore be used to model the fatigue behavior of any material, provided that sufficient data are available for training. They are material indep...
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#1Anastasios P. Vassilopoulos (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 28
#2Julia MaierH-Index: 2
Last. Christian Gaier (Steyr Mannlicher)H-Index: 6
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Abstract Structural testing is probably the best and only way to reveal the actual performance of composite laminates, structural components, and complete composite structures under fatigue loading. Nevertheless, the high cost, and the multitude of loading cases a composite structure can face during operation, hinder the possibility of developing methods based solely on experimental results and therefore, theoretical modeling procedures become essential. The complexity of the calculations and mo...
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#1Anastasios P. Vassilopoulos (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 28
Abstract The accurate modeling of the fatigue behavior of composite materials under constant amplitude (CA) cyclic stress is in itself a difficult task but when loading is of variable amplitude (VA), the situation is even more complicated since an appropriate damage metric and rules for its summation must be defined. One of the widely used approaches is based on the theoretical formulation and use of a damage summation rule to predict life under VA loading without recourse to experimental observ...
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#1Anastasios P. Vassilopoulos (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 28
Abstract This chapter aims to provide an overview of the fatigue life modeling and prediction methods for composite materials and structures, recalling methods used in the past, discovering the present status, and attempting to foresee future trends.
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#1Zhengwen Jiang (Hunan University)H-Index: 2
#2Shui Wan (SEU: Southeast University)H-Index: 2
Last. Anastasios P. Vassilopoulos (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 28
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Abstract This work investigated the evolution of the non-uniform distribution of Mode-I strain energy release rate (SERR) along a straight pre-crack front of double cantilever beams (DCB), caused by the anticlastic deformation and the longitudinal free-edge effects. A modified DCB specimen with a curved pre-crack front was introduced in order to alleviate this problem and produce an uniform SERR distribution at the initiation and propagation stages. The first order optimization method was used t...
2 CitationsSource
#1Joëlle Baehr-Bruyère (EPFL: École Polytechnique Fédérale de Lausanne)
#2Kynthia Chamilothori (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 5
Last. Marilyne Andersen (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 32
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#1A. Vahid Movahedi-Rad (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 5
#2Thomas Keller (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 45
Last. Anastasios P. Vassilopoulos (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 28
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Abstract The effect of the stress ratio (R = σmin/σmax) on the fatigue behavior of (±45)2S angle-ply glass/epoxy composite laminates was investigated by comparing their mechanical, thermal, and optical properties under the stress ratio of 0.5 with previous fatigue results obtained under the stress ratio of 0.1. When the stress ratio was increased from 0.1 to 0.5, the fatigue life was enhanced at the same σmax and the slope of S-N curve decreased, exhibiting more scattered responses. In addition,...
4 CitationsSource
#1A. Vahid Movahedi-Rad (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 5
#2Thomas Keller (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 45
Last. Anastasios P. Vassilopoulos (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 28
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Abstract A general constitutive equation was established using the theory of viscoelasticity in order to consider the interaction of the time- and cyclic-dependent mechanical properties of laminated composites. This equation was solved for two specific loading patterns, (1) stress unloading to zero stress level (recovery solution), and (2) load control sinusoidal loading (fatigue solution), and was subsequently imported to model tensile-tensile interrupted fatigue experiments (including recovery...
3 CitationsSource
#1Aida Cameselle-Molares (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 4
#2Anastasios P. Vassilopoulos (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 28
Last. Thomas Keller (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 45
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Abstract An experimental investigation of the two-dimensional (2D) debonding behavior of GFRP/balsa sandwich panels with embedded circular disbonds at the face sheet/core interface subjected to out-of-plane fatigue loads was conducted. The constant amplitude fatigue experiments were performed under load control and different R-ratios. Two face sheet configurations were investigated: a pure woven ply layup (SPA) and a combination of continuous filament mat (CFM) and woven plies (SPB). For the lat...
5 CitationsSource
#1A. Vahid Movahedi-Rad (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 5
#2Thomas Keller (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 45
Last. Anastasios P. Vassilopoulos (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 28
view all 3 authors...
Abstract Angle-ply (±45)2S glass/epoxy composite specimens have been subjected to pure creep and tension-tension constant amplitude fatigue loading interrupted at σmax by creep intervals lasting for 2 or 48 h in order to examine the effects of creep loading on the fatigue response and vice versa. The specimens’ behavior and damage status were continuously monitored during the experiments; strains were measured by a video extensometer, the self-generated temperature on the specimens’ surface was ...
14 CitationsSource