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Hygrothermal effects on fatigue delamination behavior in composite laminates

Yao, Liaojun (author), Wang, Jiexiong (author), He, Yonglyu (author), Zhao, Xiuhui (author), Chen, Xiangming (author), Liu, J. (author), Guo, Licheng (author), Alderliesten, R.C. (author)

Fatigue delamination growth (FDG) is an important failure in composite structures during their long-term operations. Hygrothermal aging can have significant effects on interlaminar resistance. It is therefore really necessary to explore FDG behavior in composite laminates with hygrothermal aging. Dynamic mechanical thermal analysis (DMTA),...

journal article 2024

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Planar delamination behaviour of CFRP panels under quasi-static out-of-plane loading

Tu, W. (author), Pascoe, J.A. (author), Alderliesten, R.C. (author)

In this study, a novel experimental approach was devised to investigate shear dominant and combined opening-shear planar delamination behaviours in composite laminates subjected to quasi-static out-of-plane loading. The patterns of planar delamination growth were depicted through different inspection techniques, including digital image...

journal article 2024

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Investigation of mode-II delamination fracture energy with a discontinuous computational homogenization model

Ke, L. (author), van der Meer, F.P. (author)

Numerical methods for delamination analysis, such as the cohesive zone method, require fracture energy as an essential input. Existing formulations rely on a phenomenological relationship that links fracture energy to the mode of fracture based on linear elastic fracture mechanics (LEFM). However, doubts exist about the applicability of LEFM....

journal article 2024

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Accurate simulation of delamination under mixed-mode loading using a multilinear cohesive law

Abdel-Monsef, S. (author), Tijs, B.H.A.H. (author), Renart, J. (author), Turon, A. (author)

The complex failure mechanisms involved in failure of interfaces requires the use of an accurate description of the cohesive law. In recent years, there have been many developments to determine the full shape of the cohesive law. However, most of the existing cohesive zone models assume a simplified shape, such as bilinear, trapezoidal or...

journal article 2023

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Experimental study of post-buckled single-stringer composite specimens under fatigue loads with different load levels and load ratios

Paz Mendez, J. (author), Raimondo, A. (author), Bisagni, C. (author)

This study aims at better understanding the damage tolerance of stiffened composite panels subjected to fatigue loads in the post-buckling regime. Ten single-stringer hat-stiffened specimens with an initial delamination between the skin and the stringer foot were manufactured, and then tested under quasi-static and fatigue loads in post...

journal article 2023

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Delamination link-ups in composite laminates due to multiple hail impacts

Sadighi, M. (author), Alderliesten, R.C. (author), Fathi, Azadeh (author), Soltannia‬, Babak (author), Hedayati, R. (author)

Damages to aircraft fuselages by ice impactors are categorized as barely visible impact damage (BVID). As the application of composite laminates in manufacturing aircraft fuselage is increasing rapidly, studying hail impact on composite laminates seems crucial. Investigation of variation of delamination area and link-up area for different...

journal article 2023

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Investigating apparent plateau phases in fatigue after impact damage growth in CFRP with ultrasound scan and acoustic emissions

Biagini, D. (author), Pascoe, J.A. (author), Alderliesten, R.C. (author)

In previous literature, a plateau phase in fatigue growth of impact delamination projected area in CFRP was found. Explaining this plateau phase still represents a knowledge gap. In the present work, echo-pulse and through thickness transmission ultrasonic scan inspections were combined with acoustic emission monitoring to explain this...

journal article 2023

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In-situ damage mechanism investigation and a prediction model for delamination with fibre bridging in composites

Yao, Liaojun (author), Liu, J. (author), Lyu, Zhangming (author), Alderliesten, R.C. (author), Hao, Cui (author), Ren, Chuanxi (author), Guo, Licheng (author)

Carbon-fibre reinforced composites are susceptible to delamination. Fibre bridging is an important shielding mechanism frequently observed in delamination. The presence of these bridging fibres can significantly increase interlaminar resistance, making it critical to represent this phenomenon for delamination characterization in composite...

journal article 2023

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Early fatigue damage accumulation of CFRP Cross-Ply laminates considering size and stress level effects

Li, X. (author), Benedictus, R. (author), Zarouchas, D. (author)

Ply-block size and stress level effect on accumulation of transverse cracks and delamination are investigated during early fatigue life of CFRP laminates. Tension-tension fatigue tests under different stress levels were performed for two cross-ply configurations. Edge observation with digital cameras, digital image correlation and acoustic...

journal article 2022

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An adaptive floating node based formulation for the analysis of multiple delaminations under quasi-static loading

Trabal, Guillem Gall (author), Bak, Brian Lau Verndal (author), Chen, B. Y. (author), Lindgaard, Esben (author)

A novel and efficient numerical formulation for the modelling of multiple delaminations growth in laminated composite materials subjected to quasi-static loading is presented. The proposed formulation alleviates the high computational cost associated with models featuring cohesive elements by using a novel Adaptive Refinement Scheme and an...

journal article 2022

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An adaptive floating node based formulation for the analysis of multiple delaminations under high cycle fatigue loading

Trabal, Guillem Gall (author), Bak, Brian Lau Verndal (author), Chen, B. Y. (author), Carreras, Laura (author), Lindgaard, Esben (author)

A novel efficient numerical formulation for the analysis of multiple fatigue-driven delamination cracks is presented. A cohesive zone model is used in combination with an Adaptive Refinement Scheme (ARS) and an Adaptive Floating Node Method (A-FNM) element that refine the model effectively during the analysis. Novel techniques are proposed to...

journal article 2022

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Exploring water and ion transport process at silicone/copper interfaces using in-situ electrochemical and Kelvin probe approaches

Munirathinam, B. (author), van Dam, J.P.B. (author), Herrmann, Annemarie (author), van Driel, W.D. (author), De Buyl, F. (author), Erich, S. J.F. (author), van der Ven, L.G.J. (author), Adan, O. C.G. (author), Mol, J.M.C. (author)

In general, packaging materials which encapsulate light emitting diodes (LEDs) and microelectronic devices offer barrier protection against several environmental hazards such as water and ionic contaminants. However, these encapsulants may provide pathways for water and ionic contaminants to reach the metal/polymer interfaces and provoke local...

journal article 2021

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Static and dynamic testing of delamination in hybrid SHCC/concrete beams

Cabboi, A. (author), Harrass, Othman (author), Sánchez Gómez, S. (author), Lukovic, M. (author)

The focus of this study is to characterize delamination using static and dynamic tests and to assess the interface failure mechanism of an innovative hybrid concrete beam, made out of conventional concrete and a special class of fibre reinforced material, known as Strain Hardening Cementitious Composite (SHCC). Three SHCC beams were subject to...

journal article 2021

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Fatigue analysis of a post-buckled composite single-stringer specimen taking into account the local stress ratio

Raimondo, A. (author), Bisagni, C. (author)

The fatigue life prediction of post-buckled composite structures represents still an unresolved issue due to the complexity of the phenomenon and the high costs of experimental testing. In this paper, a novel numerical approach, called “Min-Max Load Approach”, is used to analyze the behavior of a composite single-stringer specimen with an...

journal article 2020

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Scrutinizing interlaminar fatigue loading cycle in composites using acoustic emission technique: Stress ratio influence on damage formation

Ferreira Motta Junior, R. (author), Alderliesten, R.C. (author), Shiinoc, Marcos Yutaka (author), Cioffia, Maria Odila Hilário (author), Voorwald, Herman Jacobus Cornelis (author)

Current models for delamination propagation prediction in fiber-reinforced polymer (FRP) composites exhibit limitations to explain the physics underlying the mechanisms of damage formation in fatigue. In order to contribute in this field, this research focuses on the study of damage development within a single loading cycle of FRP double...

journal article 2020

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Development of a physics-based theory for mixed mode I/II delamination onset in orthotropic laminates

Daneshjoo, Z. (author), Amaral, L. (author), Alderliesten, R.C. (author), Shokrieh, M. M. (author), Fakoor, M. (author)

This paper demonstrates how the critical strain energy density in the delamination tip vicinity may be used to explain the physics of delamination growth under mixed mode I/II. A theory previously proposed to physically relate mode I and mode II delamination growth is further extended towards describing the onset of mixed mode I/II...

journal article 2019

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Determining finite-width-correction factors for fatigue crack growth prediction in GLARE using the equivalent compliance method

Zhao, Yuan (author), Alderliesten, R.C. (author), Wu, Zengwen (author), Zhou, Zhengong (author), Fang, Guodong (author), Zhang, Jiazhen (author), Benedictus, R. (author)

Finite-width-correction factors (FWCF) are required for GLARE to accurately predict fatigue crack growth using linear elastic fracture mechanics. As demonstrated in earlier work, these factors effectively correct for the change in specimen compliance, which in GLARE relates to intact fibre layers and the formation of delaminations between...

journal article 2019

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Physics of delamination onset in unidirectional composite laminates under mixed-mode I/II loading

Daneshjoo, Z. (author), Shokrieh, Mahmood M. (author), Fakoor, Mahdi (author), Alderliesten, R.C. (author), Zarouchas, D. (author)

In order to understand the physics of the delamination onset in laminated composites, an experimental investigation of delamination growth is presented. The main objective of this paper is to demonstrate that delamination onset occurs at lower values than Gc defined by the ASTM standards, and that the strain energy release rate level at which...

journal article 2019

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A new mixed mode I/II failure criterion for laminated composites considering fracture process zone

Daneshjoo, Z. (author), Shokrieh, M. M. (author), Fakoor, M. (author), Alderliesten, R.C. (author)

In this paper, by considering the absorbed energy in the fracture process zone and extension of the minimum strain energy density theory for orthotropic materials, a new mixed mode I/II failure criterion was proposed. The applicability of the new criterion, to predict the crack growth in both laminated composites and wood species, was...

journal article 2018

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Acoustic Emission-Based Methodology to Evaluate Delamination Crack Growth Under Quasi-static and Fatigue Loading Conditions

Saeedifar, M. (author), Ahmadi Najafabadi, Mehdi (author), Mohammadi, Kaivan (author), Fotouhi, Mohamad (author), Hosseini Toudeshky, Hossein (author), Shah Mohammadi, Mohammad Reza (author)

The aim of this study was to investigate the applicability of acoustic emission (AE) technique to evaluate delamination crack in glass/epoxy composite laminates under quasi-static and fatigue loading. To this aim, double cantilever beam specimens were subjected to mode I quasi-static and fatigue loading conditions and the generated AE signals...

journal article 2018