UNIVERSITATIS ACTA UPSALIENSIS
UPPSALA
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 1828
On numerical analyses of woven composite laminates
Homogenization, damage and fracture
JUAN JOSÉ ESPADAS ESCALANTE
ISSN 1651-6214
ISBN 978-91-513-0699-5
Dissertation presented at Uppsala University to be publicly examined in Siegbahnsalen, The Ȧngström Laboratory, Lägerhuddsvägen 1, Uppsala, Friday, 13 September 2019 at 09:15 for the degree of Doctor of Philosophy. The examination will be conducted in English. Faculty examiner: Martin Fagerström (Chalmers tekniska högskola).
Abstract
Espadas Escalante, J. J. 2019. On numerical analyses of woven composite laminates.
Homogenization, damage and fracture. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 1828. 53 pp. Uppsala: Acta Universitatis Upsaliensis. ISBN 978-91-513-0699-5.
This dissertation analyzes various mechanical properties of textile reinforced composite laminates.
The dissertation is based on a total of six published works, which are essentially numerical, although experimental elements are available. The numerical methods used are based on high- resolution finite element models in combination with sophisticated phase-field theories for brittle fracture. A key result is that important mechanical properties in engineering applications, such as fracture or damage resistance, can be substantially affected by the arrangement of the constituent materials at the meso level.
Juan José Espadas Escalante, Department of Engineering Sciences, Applied Mechanics, 516, Uppsala University, SE-751 20 Uppsala, Sweden.
© Juan José Espadas Escalante 2019 ISSN 1651-6214
ISBN 978-91-513-0699-5
urn:nbn:se:uu:diva-388808 (http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-388808)
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Figure 1.1. Worldwide awareness of the use of lightweight structures in the auto- motive industry. a) Correlation between CO 2 emissions and car weight for different transmissions, b) established regulations worldwide aiming to reduce CO 2 emis- sions. (After [5]).
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Figure 2.2. Approaches for damage modeling at different scales. a) Microscopic scale, b) mesoscopic scale (anisotropic damage model calibrated from the micro- scopic scale).
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b)
Figure 2.3. A comparison of the micro-scale approach using the GMC at an integra- tion point level and meso-scale approach using the calibrated continuum damage model. a) Fractional reduction of the C 22 component of the stiffness tensor under transverse tension, b) fractional reduction of the C 12 component of the stiffness tensor under in-plane shear. After [22].
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