Microstructural length scale parameters to model the high-cycle fatigue behaviour of notched plain concrete

Jadallah, O.; Bagni, Cristian; Askes, Harm; Susmel, Luca

doi:10.1016/j.ijfatigue.2015.09.029

Cited by 33 publications

(20 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Probably originating from a preexisting crack, a crack has grown through grains and cement, spalling a piece of grain at the surface of the specimen. Figure 7 shows the CT images of the cross section of a specimen made of Concrete 2 that failed after 9.6 × 10 7 cycles at stress level S max = 0.43 f c . A crack, probably originating from the interface of grain and cement, runs through the cement.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Very high cycle fatigue testing of concrete using ultrasonic cycling

Karr¹,

Schuller²,

Fitzka³

et al. 2017

Materials Testing

View full text Add to dashboard Cite

The ultrasonic fatigue testing method has been further developed to perform cyclic compression tests with concrete. Cylindrical specimens vibrate in resonance at a frequency of approximately 20 kHz with superimposed compressive static loads. The high testing frequency allows time-saving investigations in the very high cycle fatigue regime. Fatigue tests were carried out on “Concrete 1” (compressive strength fc = 80 MPa) and “Concrete 2” (fc = 107 MPa) under purely compressive loading conditions. Experiments at maximum compressive stresses of 0.44 fc (Concrete 1) and 0.38 fc (Concrete 2) delivered specimen failures above 109 cycles, indicating that no fatigue limit exists for concrete below one billion load cycles. Resonance frequency, power required to resonate the specimen and second order harmonics of the vibration are used to monitor fatigue damage in situ. Specimens were scanned by X-ray computed tomography prior to and after testing. Fatigue cracks were produced by ultrasonic cycling in the very high cycle fatigue regime at interfaces of grains as well as in cement. The possibilities as well as limitations of ultrasonic fatigue testing of concrete are discussed.

show abstract

Section: Resultsmentioning

confidence: 99%

“…Concrete is subjected to cyclic compression loading in service, whereas ultra- cycles [7] to failure and fatigue limits are defined using 2 × 10 6 cycles for reference [8]. Until now, the very high cycle fatigue properties have only been theoretically approached [9].…”

mentioning

confidence: 99%

Very high cycle fatigue testing of concrete using ultrasonic cycling

Karr¹,

Schuller²,

Fitzka³

et al. 2017

Materials Testing

View full text Add to dashboard Cite

show abstract

“…In these sketches symbols F0, M0 and T0 are used to denote the amplitudes of the external forces and moments in the fatigue (endurance) limit condition. As shown in Figures 3c and 3d, the gradient-enriched fatigue (endurance) limits at the surface of the shaft, limits [32]. However, it has to be said that, in general, under both cyclic bending and cyclic torsion the difference between conventional and gradient-enriched fatigue (endurance)…”

Section: Combining Gradient Elasticity With the Tcd And The Mwcmmentioning

confidence: 94%

“…Therefore, in situations of practical interest, gradient elasticity should be used by adopting σ g 0 and τ g 0 as reference un-notched fatigue (endurance) limits. 32 However, it has to be said that, in general, under both cyclic bending and cyclic torsion the difference between conventional and gradient-enriched fatigue (endurance) limits is seen to be very little (on average, lower than about 5%). This suggests that σ 0 and τ 0 can still be used as reference fatigue strengths, provided that a little loss of accuracy is considered to be acceptable when performing the high-cycle fatigue assessment.…”

Section: O M B I N I N G G R a D I E N T E L A S T I C I T Y W I T mentioning

confidence: 99%

Gradient elasticity: a transformative stress analysis tool to design notched components against uniaxial/multiaxial high‐cycle fatigue

Bagni

Askes

Susmel

2016

Fatigue Fract Eng Mat Struct

View full text Add to dashboard Cite

ReuseUnless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section 29 of the Copyright, Designs and Patents Act 1988 allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version -refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher's website. TakedownIf you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing eprints@whiterose.ac.uk including the URL of the record and the reason for the withdrawal request.Please This comprehensive validation exercise demonstrates that the systematic usage of this transformative design approach leads to the same level of accuracy as the one which is obtained by applying the classic Theory of Critical Distances. This result is certainly remarkable since the proposed approach is not only very efficient from a computational point of view, but it also allows high-cycle fatigue damage to be assessed by directly postprocessing gradient-enriched stress states determined on the surface of the component being assessed., cite this paper as: Bagni, C., Askes, H., Susmel, L. Gradient elasticity: a transformative stress analysis tool to design notched components against uniaxial/multiaxial high-cycle fatigue. Fatigue Fract Engng Mater Struct. 39 8, pp. 1012-1029

show abstract

“…Here gradient elasticity theories come into play; in fact, as extensively discussed and proven in the literature (see, for instance, [10,15,17,19,20,42,46]), they are able to overcome the deficiencies of classical elasticity in accurately determining the stress fields in specific problems, especially those for which it is necessary to account for microand nanoscale effects in the description of the overall macroscopic response. In particular, gradient-enriched theories are able to remove singularities from (micro-)stress and (micro-)strain fields in the neighbourhood of sharp crack tips and, in general, they have a smoothing effect on the stresses in the presence of stress concentrators, such as notches and holes.…”

Section: Introductionmentioning

confidence: 99%

Gradient-enriched finite element methodology for axisymmetric problems

2017

Self Cite

View full text Add to dashboard Cite

Due to the axisymmetric nature of many engineering problems, bi-dimensional axisymmetric finite elements play an important role in the numerical analysis of structures, as well as advanced technology micro/ nano-components and devices (nano-tubes, nano-wires, micro-/nano-pillars, micro-electrodes). In this paper, a straightforward C 0 -continuous gradient-enriched finite element methodology is proposed for the solution of axisymmetric geometries, including both axisymmetric and non-axisymmetric loads. Considerations about the best integration rules and an exhaustive convergence study are also provided along with guidances on optimal element size. Moreover, by applying the present methodology to cylindrical bars characterised by a circumferential sharp crack, the ability of the present methodology to remove singularities from the stress field has been shown under axial, bending, and torsional loading conditions. Some preliminary results, obtained by applying the proposed methodology to notched cylindrical bars, are also presented, highlighting the accuracy of the methodology in the static and fatigue assessment of notched components, for both brittle and ductile materials. Finally, the proposed methodology has been applied to model the unit cell of the anode of Li-ion batteries showing the ability of the methodology to account for size effects.

show abstract

Microstructural length scale parameters to model the high-cycle fatigue behaviour of notched plain concrete

Cited by 33 publications

References 36 publications

Very high cycle fatigue testing of concrete using ultrasonic cycling

Very high cycle fatigue testing of concrete using ultrasonic cycling

Gradient elasticity: a transformative stress analysis tool to design notched components against uniaxial/multiaxial high‐cycle fatigue

Gradient-enriched finite element methodology for axisymmetric problems

Contact Info

Product

Resources

About