---
_id: '64187'
abstract:
- lang: eng
  text: <jats:p>Carbon fiber-reinforced plastics (CFRPs) have become increasingly
    significant in recent decades due to their remarkable mechanical properties and
    lightweight nature. This study aims to advance the understanding and simulation
    of CFRP behavior through the development of a hyperelastic-plastic-damage homogenization
    method combined with mean-field theory. The material responses of both the fiber
    and matrix are modeled using strain energy functions that account for damage evolution,
    while a complete linearization of the homogenization process is derived to ensure
    the consistent implementation of the Newton–Raphson iteration scheme in large
    deformation simulations. The innovative aspect of this work lies in the constitutive
    linearization for the hyperelastic-plastic-damage formulation within a mean-field
    homogenization framework, providing an efficient Newton algorithm for modeling
    the nonlinear behavior of CFRP. A failure criterion for the hyperelastic model
    of fibers is introduced, along with a damage saturation variable in rate form
    for the matrix, effectively capturing damage evolution. Through discrete formulations
    for the homogenization, the proposed model’s capability is demonstrated via three
    numerical examples and validated against experimental investigations, proving
    its effectiveness and reliability in simulating CFRP damage.</jats:p>
article_number: '10812865261420809'
author:
- first_name: Yingjie
  full_name: Zhan, Yingjie
  id: '93591'
  last_name: Zhan
- first_name: Ismail
  full_name: Caylak, Ismail
  last_name: Caylak
- first_name: Richard
  full_name: Ostwald, Richard
  id: '106876'
  last_name: Ostwald
  orcid: 0000-0003-2147-8444
- first_name: Rolf
  full_name: Mahnken, Rolf
  id: '335'
  last_name: Mahnken
- first_name: Enrico
  full_name: Barth, Enrico
  last_name: Barth
- first_name: Eckart
  full_name: Uhlmann, Eckart
  last_name: Uhlmann
citation:
  ama: Zhan Y, Caylak I, Ostwald R, Mahnken R, Barth E, Uhlmann E. A fully implicit
    mean-field damage formulation with consistent linearization at large deformations.
    <i>Mathematics and Mechanics of Solids</i>. Published online 2026. doi:<a href="https://doi.org/10.1177/10812865261420809">10.1177/10812865261420809</a>
  apa: Zhan, Y., Caylak, I., Ostwald, R., Mahnken, R., Barth, E., &#38; Uhlmann, E.
    (2026). A fully implicit mean-field damage formulation with consistent linearization
    at large deformations. <i>Mathematics and Mechanics of Solids</i>, Article 10812865261420808.
    <a href="https://doi.org/10.1177/10812865261420809">https://doi.org/10.1177/10812865261420809</a>
  bibtex: '@article{Zhan_Caylak_Ostwald_Mahnken_Barth_Uhlmann_2026, title={A fully
    implicit mean-field damage formulation with consistent linearization at large
    deformations}, DOI={<a href="https://doi.org/10.1177/10812865261420809">10.1177/10812865261420809</a>},
    number={10812865261420808}, journal={Mathematics and Mechanics of Solids}, publisher={SAGE
    Publications}, author={Zhan, Yingjie and Caylak, Ismail and Ostwald, Richard and
    Mahnken, Rolf and Barth, Enrico and Uhlmann, Eckart}, year={2026} }'
  chicago: Zhan, Yingjie, Ismail Caylak, Richard Ostwald, Rolf Mahnken, Enrico Barth,
    and Eckart Uhlmann. “A Fully Implicit Mean-Field Damage Formulation with Consistent
    Linearization at Large Deformations.” <i>Mathematics and Mechanics of Solids</i>,
    2026. <a href="https://doi.org/10.1177/10812865261420809">https://doi.org/10.1177/10812865261420809</a>.
  ieee: 'Y. Zhan, I. Caylak, R. Ostwald, R. Mahnken, E. Barth, and E. Uhlmann, “A
    fully implicit mean-field damage formulation with consistent linearization at
    large deformations,” <i>Mathematics and Mechanics of Solids</i>, Art. no. 10812865261420808,
    2026, doi: <a href="https://doi.org/10.1177/10812865261420809">10.1177/10812865261420809</a>.'
  mla: Zhan, Yingjie, et al. “A Fully Implicit Mean-Field Damage Formulation with
    Consistent Linearization at Large Deformations.” <i>Mathematics and Mechanics
    of Solids</i>, 10812865261420808, SAGE Publications, 2026, doi:<a href="https://doi.org/10.1177/10812865261420809">10.1177/10812865261420809</a>.
  short: Y. Zhan, I. Caylak, R. Ostwald, R. Mahnken, E. Barth, E. Uhlmann, Mathematics
    and Mechanics of Solids (2026).
date_created: 2026-02-17T11:21:00Z
date_updated: 2026-02-17T11:22:49Z
department:
- _id: '9'
- _id: '952'
- _id: '321'
doi: 10.1177/10812865261420809
language:
- iso: eng
publication: Mathematics and Mechanics of Solids
publication_identifier:
  issn:
  - 1081-2865
  - 1741-3028
publication_status: published
publisher: SAGE Publications
quality_controlled: '1'
status: public
title: A fully implicit mean-field damage formulation with consistent linearization
  at large deformations
type: journal_article
user_id: '85414'
year: '2026'
...
---
_id: '65266'
abstract:
- lang: eng
  text: "<jats:title>ABSTRACT</jats:title>\r\n                  <jats:p>This work
    is concerned with the modeling of a cold‐box sand, a composition of sand grains
    and a resin binder. To this end, experiments are performed, which show the following
    characteristics: localization phenomena in the form of a shear band, softening
    behavior in the force‐displacement curve, and asymmetric behavior for compression
    and tension. To model this complex material behavior, a micromorphic continuum
    is used. In the present contribution, we focus on the linear‐elastic regime and
    demonstrate the identifiability of micromorphic material parameters under deliberately
    induced inhomogeneous deformation states. In addition to the degrees of freedom
    of a classical continuum, the micromorphic model has additional degrees of freedom,
    introduced here in a phenomenological sense to represent kinematically enriched
    deformation modes associated with the granular microstructure. Accordingly, the
    micromorphic fields are not interpreted as a separate physical scale (e.g., “binder”
    vs. “grains”), but as an effective continuum description at the specimen scale.
    This contribution addresses parameter identification for a micromorphic model
    of cold‐box sand, with a clear separation between homogeneous deformation states
    governing classical elastic parameters and inhomogeneous states required to activate
    and identify micromorphic length‐scale parameters. The main challenge lies in
    identifying the micro material parameters. To determine these, the corresponding
    gradient terms in the constitutive formulation must be triggered via properly
    tuned experiments. Micro‐parameter identification is demonstrated using synthetic
    data generated from a boundary‐value problem with inhomogeneous displacement fields.
    The chosen benchmark enables controlled activation of gradient terms and thereby
    renders optimization‐based identification of micromorphic parameters feasible.
    The synthetic example is deliberately chosen to assess feasibility and identifiability
    under controlled conditions, thereby isolating micromorphic identifiability aspects
    from experimental uncertainties. The novelty of the contribution lies in explicitly
    linking micromorphic parameter identifiability to kinematic inhomogeneity, and
    in demonstrating this link within a tractable forward– inverse setting for a linear‐elastic
    micromorphic continuum.</jats:p>"
article_number: e70093
author:
- first_name: Alexander
  full_name: Börger, Alexander
  id: '52037'
  last_name: Börger
- first_name: Rolf
  full_name: Mahnken, Rolf
  last_name: Mahnken
- first_name: Ismail
  full_name: Caylak, Ismail
  id: '75'
  last_name: Caylak
- first_name: Richard
  full_name: Ostwald, Richard
  id: '106876'
  last_name: Ostwald
  orcid: 0000-0003-2147-8444
citation:
  ama: Börger A, Mahnken R, Caylak I, Ostwald R. Aspects of Parameter Identification
    for a Micromorphic Continuum applied to a Cold‐Box Sand. <i>Proceedings in Applied
    Mathematics and Mechanics</i>. 2026;26(2). doi:<a href="https://doi.org/10.1002/pamm.70093">10.1002/pamm.70093</a>
  apa: Börger, A., Mahnken, R., Caylak, I., &#38; Ostwald, R. (2026). Aspects of Parameter
    Identification for a Micromorphic Continuum applied to a Cold‐Box Sand. <i>Proceedings
    in Applied Mathematics and Mechanics</i>, <i>26</i>(2), Article e70093. <a href="https://doi.org/10.1002/pamm.70093">https://doi.org/10.1002/pamm.70093</a>
  bibtex: '@article{Börger_Mahnken_Caylak_Ostwald_2026, title={Aspects of Parameter
    Identification for a Micromorphic Continuum applied to a Cold‐Box Sand}, volume={26},
    DOI={<a href="https://doi.org/10.1002/pamm.70093">10.1002/pamm.70093</a>}, number={2e70093},
    journal={Proceedings in Applied Mathematics and Mechanics}, publisher={Wiley},
    author={Börger, Alexander and Mahnken, Rolf and Caylak, Ismail and Ostwald, Richard},
    year={2026} }'
  chicago: Börger, Alexander, Rolf Mahnken, Ismail Caylak, and Richard Ostwald. “Aspects
    of Parameter Identification for a Micromorphic Continuum Applied to a Cold‐Box
    Sand.” <i>Proceedings in Applied Mathematics and Mechanics</i> 26, no. 2 (2026).
    <a href="https://doi.org/10.1002/pamm.70093">https://doi.org/10.1002/pamm.70093</a>.
  ieee: 'A. Börger, R. Mahnken, I. Caylak, and R. Ostwald, “Aspects of Parameter Identification
    for a Micromorphic Continuum applied to a Cold‐Box Sand,” <i>Proceedings in Applied
    Mathematics and Mechanics</i>, vol. 26, no. 2, Art. no. e70093, 2026, doi: <a
    href="https://doi.org/10.1002/pamm.70093">10.1002/pamm.70093</a>.'
  mla: Börger, Alexander, et al. “Aspects of Parameter Identification for a Micromorphic
    Continuum Applied to a Cold‐Box Sand.” <i>Proceedings in Applied Mathematics and
    Mechanics</i>, vol. 26, no. 2, e70093, Wiley, 2026, doi:<a href="https://doi.org/10.1002/pamm.70093">10.1002/pamm.70093</a>.
  short: A. Börger, R. Mahnken, I. Caylak, R. Ostwald, Proceedings in Applied Mathematics
    and Mechanics 26 (2026).
date_created: 2026-04-01T04:52:34Z
date_updated: 2026-04-01T04:54:17Z
department:
- _id: '9'
- _id: '952'
- _id: '321'
doi: 10.1002/pamm.70093
intvolume: '        26'
issue: '2'
language:
- iso: eng
publication: Proceedings in Applied Mathematics and Mechanics
publication_identifier:
  issn:
  - 1617-7061
  - 1617-7061
publication_status: published
publisher: Wiley
quality_controlled: '1'
status: public
title: Aspects of Parameter Identification for a Micromorphic Continuum applied to
  a Cold‐Box Sand
type: journal_article
user_id: '85414'
volume: 26
year: '2026'
...
---
_id: '65458'
author:
- first_name: Ayoub
  full_name: Hamdoun, Ayoub
  id: '57708'
  last_name: Hamdoun
- first_name: Rolf
  full_name: Mahnken, Rolf
  id: '335'
  last_name: Mahnken
- first_name: Richard
  full_name: Ostwald, Richard
  id: '106876'
  last_name: Ostwald
  orcid: 0000-0003-2147-8444
citation:
  ama: 'Hamdoun A, Mahnken R, Ostwald R. A gradient-damage model for amorphous glassy
    polymers: Consistent formulation of viscoplasticity and damage evolution in a
    micromorphic framework. <i>European Journal of Mechanics / A Solids</i>. Published
    online 2026. doi:<a href="https://doi.org/10.1016/j.euromechsol.2026.106137">https://doi.org/10.1016/j.euromechsol.2026.106137</a>'
  apa: 'Hamdoun, A., Mahnken, R., &#38; Ostwald, R. (2026). A gradient-damage model
    for amorphous glassy polymers: Consistent formulation of viscoplasticity and damage
    evolution in a micromorphic framework. <i>European Journal of Mechanics / A Solids</i>.
    <a href="https://doi.org/10.1016/j.euromechsol.2026.106137">https://doi.org/10.1016/j.euromechsol.2026.106137</a>'
  bibtex: '@article{Hamdoun_Mahnken_Ostwald_2026, title={A gradient-damage model for
    amorphous glassy polymers: Consistent formulation of viscoplasticity and damage
    evolution in a micromorphic framework}, DOI={<a href="https://doi.org/10.1016/j.euromechsol.2026.106137">https://doi.org/10.1016/j.euromechsol.2026.106137</a>},
    journal={European Journal of Mechanics / A Solids}, author={Hamdoun, Ayoub and
    Mahnken, Rolf and Ostwald, Richard}, year={2026} }'
  chicago: 'Hamdoun, Ayoub, Rolf Mahnken, and Richard Ostwald. “A Gradient-Damage
    Model for Amorphous Glassy Polymers: Consistent Formulation of Viscoplasticity
    and Damage Evolution in a Micromorphic Framework.” <i>European Journal of Mechanics
    / A Solids</i>, 2026. <a href="https://doi.org/10.1016/j.euromechsol.2026.106137">https://doi.org/10.1016/j.euromechsol.2026.106137</a>.'
  ieee: 'A. Hamdoun, R. Mahnken, and R. Ostwald, “A gradient-damage model for amorphous
    glassy polymers: Consistent formulation of viscoplasticity and damage evolution
    in a micromorphic framework,” <i>European Journal of Mechanics / A Solids</i>,
    2026, doi: <a href="https://doi.org/10.1016/j.euromechsol.2026.106137">https://doi.org/10.1016/j.euromechsol.2026.106137</a>.'
  mla: 'Hamdoun, Ayoub, et al. “A Gradient-Damage Model for Amorphous Glassy Polymers:
    Consistent Formulation of Viscoplasticity and Damage Evolution in a Micromorphic
    Framework.” <i>European Journal of Mechanics / A Solids</i>, 2026, doi:<a href="https://doi.org/10.1016/j.euromechsol.2026.106137">https://doi.org/10.1016/j.euromechsol.2026.106137</a>.'
  short: A. Hamdoun, R. Mahnken, R. Ostwald, European Journal of Mechanics / A Solids
    (2026).
date_created: 2026-04-18T07:19:21Z
date_updated: 2026-04-20T11:28:43Z
ddc:
- '620'
department:
- _id: '9'
- _id: '952'
- _id: '321'
doi: https://doi.org/10.1016/j.euromechsol.2026.106137
file:
- access_level: open_access
  content_type: application/pdf
  creator: ahamdoun
  date_created: 2026-04-18T07:19:12Z
  date_updated: 2026-04-18T07:19:12Z
  file_id: '65459'
  file_name: 1-s2.0-S0997753826001233-main.pdf
  file_size: 3153415
  relation: main_file
file_date_updated: 2026-04-18T07:19:12Z
has_accepted_license: '1'
language:
- iso: eng
oa: '1'
publication: European Journal of Mechanics / A Solids
status: public
title: 'A gradient-damage model for amorphous glassy polymers: Consistent formulation
  of viscoplasticity and damage evolution in a micromorphic framework'
type: journal_article
user_id: '57708'
year: '2026'
...
---
_id: '65491'
abstract:
- lang: eng
  text: "<jats:title>Abstract</jats:title>\r\n                  <jats:p>The micropolar
    continuum is a special case of a micromorphic material model and has additional
    degrees of freedom in the form of microrotations compared to the classical continuum.
    With the micropolar model, size effects can be considered and the boundary value
    problem can be regularized when localization effects occur. In order to map the
    microrotations, an additional strain measure and an additional stress are introduced.
    For simulation of plasticity, it is possible to define one yield function, and
    thus one plastic multiplier as well as one equivalent plastic strain occur. This
    approach is known as the single-surface plasticity approach. The macro- and micro-stresses
    are coupled in a common flow function. On the other hand, there is the so-called
    double-surface plasticity when one yield function, one plastic multiplier, and
    one equivalent plastic strain, respectively, are introduced for each of the macro-
    and micro-variables. The coupling of the macro- and micro-variables is established
    by a possible coupling of both yield functions. The purpose of this paper is to
    compare both approaches and to identify similarities and differences.</jats:p>"
article_number: '94'
author:
- first_name: Alexander
  full_name: Börger, Alexander
  id: '52037'
  last_name: Börger
- first_name: Rolf
  full_name: Mahnken, Rolf
  last_name: Mahnken
citation:
  ama: Börger A, Mahnken R. Single-surface and double-surface plasticity for micropolar
    continuum. <i>Archive of Applied Mechanics</i>. 2026;96(5). doi:<a href="https://doi.org/10.1007/s00419-026-03049-w">10.1007/s00419-026-03049-w</a>
  apa: Börger, A., &#38; Mahnken, R. (2026). Single-surface and double-surface plasticity
    for micropolar continuum. <i>Archive of Applied Mechanics</i>, <i>96</i>(5), Article
    94. <a href="https://doi.org/10.1007/s00419-026-03049-w">https://doi.org/10.1007/s00419-026-03049-w</a>
  bibtex: '@article{Börger_Mahnken_2026, title={Single-surface and double-surface
    plasticity for micropolar continuum}, volume={96}, DOI={<a href="https://doi.org/10.1007/s00419-026-03049-w">10.1007/s00419-026-03049-w</a>},
    number={594}, journal={Archive of Applied Mechanics}, publisher={Springer Science
    and Business Media LLC}, author={Börger, Alexander and Mahnken, Rolf}, year={2026}
    }'
  chicago: Börger, Alexander, and Rolf Mahnken. “Single-Surface and Double-Surface
    Plasticity for Micropolar Continuum.” <i>Archive of Applied Mechanics</i> 96,
    no. 5 (2026). <a href="https://doi.org/10.1007/s00419-026-03049-w">https://doi.org/10.1007/s00419-026-03049-w</a>.
  ieee: 'A. Börger and R. Mahnken, “Single-surface and double-surface plasticity for
    micropolar continuum,” <i>Archive of Applied Mechanics</i>, vol. 96, no. 5, Art.
    no. 94, 2026, doi: <a href="https://doi.org/10.1007/s00419-026-03049-w">10.1007/s00419-026-03049-w</a>.'
  mla: Börger, Alexander, and Rolf Mahnken. “Single-Surface and Double-Surface Plasticity
    for Micropolar Continuum.” <i>Archive of Applied Mechanics</i>, vol. 96, no. 5,
    94, Springer Science and Business Media LLC, 2026, doi:<a href="https://doi.org/10.1007/s00419-026-03049-w">10.1007/s00419-026-03049-w</a>.
  short: A. Börger, R. Mahnken, Archive of Applied Mechanics 96 (2026).
date_created: 2026-04-23T11:55:35Z
date_updated: 2026-04-23T11:56:38Z
department:
- _id: '9'
- _id: '952'
- _id: '321'
doi: 10.1007/s00419-026-03049-w
intvolume: '        96'
issue: '5'
language:
- iso: eng
publication: Archive of Applied Mechanics
publication_identifier:
  issn:
  - 0939-1533
  - 1432-0681
publication_status: published
publisher: Springer Science and Business Media LLC
quality_controlled: '1'
status: public
title: Single-surface and double-surface plasticity for micropolar continuum
type: journal_article
user_id: '85414'
volume: 96
year: '2026'
...
---
_id: '60124'
article_number: '113465'
author:
- first_name: Hendrik
  full_name: Westermann, Hendrik
  id: '60816'
  last_name: Westermann
  orcid: 0000-0002-5034-9708
- first_name: Rolf
  full_name: Mahnken, Rolf
  last_name: Mahnken
citation:
  ama: Westermann H, Mahnken R. Thermodynamically consistent phase-field modeling
    for polycrystalline multi-phase continua. <i>International Journal of Solids and
    Structures</i>. Published online 2025. doi:<a href="https://doi.org/10.1016/j.ijsolstr.2025.113465">10.1016/j.ijsolstr.2025.113465</a>
  apa: Westermann, H., &#38; Mahnken, R. (2025). Thermodynamically consistent phase-field
    modeling for polycrystalline multi-phase continua. <i>International Journal of
    Solids and Structures</i>, Article 113465. <a href="https://doi.org/10.1016/j.ijsolstr.2025.113465">https://doi.org/10.1016/j.ijsolstr.2025.113465</a>
  bibtex: '@article{Westermann_Mahnken_2025, title={Thermodynamically consistent phase-field
    modeling for polycrystalline multi-phase continua}, DOI={<a href="https://doi.org/10.1016/j.ijsolstr.2025.113465">10.1016/j.ijsolstr.2025.113465</a>},
    number={113465}, journal={International Journal of Solids and Structures}, publisher={Elsevier
    BV}, author={Westermann, Hendrik and Mahnken, Rolf}, year={2025} }'
  chicago: Westermann, Hendrik, and Rolf Mahnken. “Thermodynamically Consistent Phase-Field
    Modeling for Polycrystalline Multi-Phase Continua.” <i>International Journal of
    Solids and Structures</i>, 2025. <a href="https://doi.org/10.1016/j.ijsolstr.2025.113465">https://doi.org/10.1016/j.ijsolstr.2025.113465</a>.
  ieee: 'H. Westermann and R. Mahnken, “Thermodynamically consistent phase-field modeling
    for polycrystalline multi-phase continua,” <i>International Journal of Solids
    and Structures</i>, Art. no. 113465, 2025, doi: <a href="https://doi.org/10.1016/j.ijsolstr.2025.113465">10.1016/j.ijsolstr.2025.113465</a>.'
  mla: Westermann, Hendrik, and Rolf Mahnken. “Thermodynamically Consistent Phase-Field
    Modeling for Polycrystalline Multi-Phase Continua.” <i>International Journal of
    Solids and Structures</i>, 113465, Elsevier BV, 2025, doi:<a href="https://doi.org/10.1016/j.ijsolstr.2025.113465">10.1016/j.ijsolstr.2025.113465</a>.
  short: H. Westermann, R. Mahnken, International Journal of Solids and Structures
    (2025).
date_created: 2025-06-03T19:48:12Z
date_updated: 2025-06-06T14:24:50Z
doi: 10.1016/j.ijsolstr.2025.113465
language:
- iso: eng
publication: International Journal of Solids and Structures
publication_identifier:
  issn:
  - 0020-7683
publication_status: published
publisher: Elsevier BV
status: public
title: Thermodynamically consistent phase-field modeling for polycrystalline multi-phase
  continua
type: journal_article
user_id: '60816'
year: '2025'
...
---
_id: '52217'
abstract:
- lang: eng
  text: <jats:title>Abstract</jats:title><jats:p>Polycarbonate (PC) is an amorphous
    polymer that is an extremely robust material with a high tenacity, and thus suitable
    for a lightweight construction with glass‐like transparency. Due to these advantageous
    properties, PC is often used in industry for example in medical devices, automotive
    headlamps, sporting equipment, electronics, and a variety of other products. PC
    is often subjected to uniaxial and biaxial loading conditions. Therefore, reliable
    material models have to take into account the various resulting experimental effects.
    For those reasons, we investigate PC specimens under uniaxial and biaxial loading
    by using different stretch rates and loading scenarios. In addition to that, we
    propose methods for optical measurement of local stretches to obtain the approximated
    local true stress. In future work, the displacement fields and the resulting reaction
    forces will be used for parameter identification of constitutive equations.</jats:p>
author:
- first_name: Ayoub
  full_name: Hamdoun, Ayoub
  last_name: Hamdoun
- first_name: Rolf
  full_name: Mahnken, Rolf
  id: '335'
  last_name: Mahnken
citation:
  ama: Hamdoun A, Mahnken R. Experimental investigations of uniaxial and biaxial cold
    stretching within PC‐films and bars using optical measurements. <i>PAMM</i>. Published
    online 2024. doi:<a href="https://doi.org/10.1002/pamm.202300114">10.1002/pamm.202300114</a>
  apa: Hamdoun, A., &#38; Mahnken, R. (2024). Experimental investigations of uniaxial
    and biaxial cold stretching within PC‐films and bars using optical measurements.
    <i>PAMM</i>. <a href="https://doi.org/10.1002/pamm.202300114">https://doi.org/10.1002/pamm.202300114</a>
  bibtex: '@article{Hamdoun_Mahnken_2024, title={Experimental investigations of uniaxial
    and biaxial cold stretching within PC‐films and bars using optical measurements},
    DOI={<a href="https://doi.org/10.1002/pamm.202300114">10.1002/pamm.202300114</a>},
    journal={PAMM}, publisher={Wiley}, author={Hamdoun, Ayoub and Mahnken, Rolf},
    year={2024} }'
  chicago: Hamdoun, Ayoub, and Rolf Mahnken. “Experimental Investigations of Uniaxial
    and Biaxial Cold Stretching within PC‐films and Bars Using Optical Measurements.”
    <i>PAMM</i>, 2024. <a href="https://doi.org/10.1002/pamm.202300114">https://doi.org/10.1002/pamm.202300114</a>.
  ieee: 'A. Hamdoun and R. Mahnken, “Experimental investigations of uniaxial and biaxial
    cold stretching within PC‐films and bars using optical measurements,” <i>PAMM</i>,
    2024, doi: <a href="https://doi.org/10.1002/pamm.202300114">10.1002/pamm.202300114</a>.'
  mla: Hamdoun, Ayoub, and Rolf Mahnken. “Experimental Investigations of Uniaxial
    and Biaxial Cold Stretching within PC‐films and Bars Using Optical Measurements.”
    <i>PAMM</i>, Wiley, 2024, doi:<a href="https://doi.org/10.1002/pamm.202300114">10.1002/pamm.202300114</a>.
  short: A. Hamdoun, R. Mahnken, PAMM (2024).
date_created: 2024-02-29T13:53:13Z
date_updated: 2024-02-29T13:58:38Z
department:
- _id: '9'
- _id: '154'
- _id: '321'
doi: 10.1002/pamm.202300114
keyword:
- Electrical and Electronic Engineering
- Atomic and Molecular Physics
- and Optics
language:
- iso: eng
publication: PAMM
publication_identifier:
  issn:
  - 1617-7061
  - 1617-7061
publication_status: published
publisher: Wiley
quality_controlled: '1'
status: public
title: Experimental investigations of uniaxial and biaxial cold stretching within
  PC‐films and bars using optical measurements
type: journal_article
user_id: '335'
year: '2024'
...
---
_id: '52218'
article_number: '112642'
author:
- first_name: Peter
  full_name: Lenz, Peter
  last_name: Lenz
- first_name: Rolf
  full_name: Mahnken, Rolf
  id: '335'
  last_name: Mahnken
citation:
  ama: Lenz P, Mahnken R. Multiscale simulation of polymer curing of composites combined
    mean-field homogenisation methods at large strains. <i>International Journal of
    Solids and Structures</i>. 2024;290. doi:<a href="https://doi.org/10.1016/j.ijsolstr.2023.112642">10.1016/j.ijsolstr.2023.112642</a>
  apa: Lenz, P., &#38; Mahnken, R. (2024). Multiscale simulation of polymer curing
    of composites combined mean-field homogenisation methods at large strains. <i>International
    Journal of Solids and Structures</i>, <i>290</i>, Article 112642. <a href="https://doi.org/10.1016/j.ijsolstr.2023.112642">https://doi.org/10.1016/j.ijsolstr.2023.112642</a>
  bibtex: '@article{Lenz_Mahnken_2024, title={Multiscale simulation of polymer curing
    of composites combined mean-field homogenisation methods at large strains}, volume={290},
    DOI={<a href="https://doi.org/10.1016/j.ijsolstr.2023.112642">10.1016/j.ijsolstr.2023.112642</a>},
    number={112642}, journal={International Journal of Solids and Structures}, publisher={Elsevier
    BV}, author={Lenz, Peter and Mahnken, Rolf}, year={2024} }'
  chicago: Lenz, Peter, and Rolf Mahnken. “Multiscale Simulation of Polymer Curing
    of Composites Combined Mean-Field Homogenisation Methods at Large Strains.” <i>International
    Journal of Solids and Structures</i> 290 (2024). <a href="https://doi.org/10.1016/j.ijsolstr.2023.112642">https://doi.org/10.1016/j.ijsolstr.2023.112642</a>.
  ieee: 'P. Lenz and R. Mahnken, “Multiscale simulation of polymer curing of composites
    combined mean-field homogenisation methods at large strains,” <i>International
    Journal of Solids and Structures</i>, vol. 290, Art. no. 112642, 2024, doi: <a
    href="https://doi.org/10.1016/j.ijsolstr.2023.112642">10.1016/j.ijsolstr.2023.112642</a>.'
  mla: Lenz, Peter, and Rolf Mahnken. “Multiscale Simulation of Polymer Curing of
    Composites Combined Mean-Field Homogenisation Methods at Large Strains.” <i>International
    Journal of Solids and Structures</i>, vol. 290, 112642, Elsevier BV, 2024, doi:<a
    href="https://doi.org/10.1016/j.ijsolstr.2023.112642">10.1016/j.ijsolstr.2023.112642</a>.
  short: P. Lenz, R. Mahnken, International Journal of Solids and Structures 290 (2024).
date_created: 2024-02-29T13:57:56Z
date_updated: 2024-02-29T13:58:14Z
department:
- _id: '9'
- _id: '154'
- _id: '321'
doi: 10.1016/j.ijsolstr.2023.112642
intvolume: '       290'
keyword:
- Applied Mathematics
- Mechanical Engineering
- Mechanics of Materials
- Condensed Matter Physics
- General Materials Science
- Modeling and Simulation
language:
- iso: eng
publication: International Journal of Solids and Structures
publication_identifier:
  issn:
  - 0020-7683
publication_status: published
publisher: Elsevier BV
quality_controlled: '1'
status: public
title: Multiscale simulation of polymer curing of composites combined mean-field homogenisation
  methods at large strains
type: journal_article
user_id: '335'
volume: 290
year: '2024'
...
---
_id: '52233'
abstract:
- lang: eng
  text: ELDIRK methods are defined to have an <jats:italic>Explicit Last</jats:italic>
    stage in the general Butcher array of <jats:italic>Diagonal Implicit Runge-Kutta</jats:italic>
    methods, with the consequence, that no additional system of equations must be
    solved, compared to the embedded RK method. Two general formulations for second-
    and third-order ELDIRK methods have been obtained recently in Mahnken [21] with
    specific schemes,  e.g. for the embedded implicit Euler method, the embedded trapezoidal-rule
    and the embedded Ellsiepen method. In the first part of this paper, we investigate
    some general stability characteristics of ELDIRK methods, and it will be shown
    that the above specific RK schemes are not A-stable. Therefore, in the second
    part, the above-mentioned general formulations are used for further stability
    investigations, with the aim to construct new second- and third-order ELDIRK methods
    which simultaneously are A-stable. Two numerical examples are concerned with the
    curing for a thermosetting material and phase-field RVE modeling for crystallinity
    and orientation. The numerical results confirm the theoretical results on convergence
    order and stability.
author:
- first_name: Rolf
  full_name: Mahnken, Rolf
  id: '335'
  last_name: Mahnken
- first_name: Hendrik
  full_name: Westermann, Hendrik
  id: '60816'
  last_name: Westermann
  orcid: 0000-0002-5034-9708
citation:
  ama: Mahnken R, Westermann H. Construction of A-stable explicit last-stage diagonal
    implicit Runge–Kutta (ELDIRK) methods. <i>Computational Mechanics</i>. Published
    online 2024. doi:<a href="https://doi.org/10.1007/s00466-024-02442-y">10.1007/s00466-024-02442-y</a>
  apa: Mahnken, R., &#38; Westermann, H. (2024). Construction of A-stable explicit
    last-stage diagonal implicit Runge–Kutta (ELDIRK) methods. <i>Computational Mechanics</i>.
    <a href="https://doi.org/10.1007/s00466-024-02442-y">https://doi.org/10.1007/s00466-024-02442-y</a>
  bibtex: '@article{Mahnken_Westermann_2024, title={Construction of A-stable explicit
    last-stage diagonal implicit Runge–Kutta (ELDIRK) methods}, DOI={<a href="https://doi.org/10.1007/s00466-024-02442-y">10.1007/s00466-024-02442-y</a>},
    journal={Computational Mechanics}, publisher={Springer Science and Business Media
    LLC}, author={Mahnken, Rolf and Westermann, Hendrik}, year={2024} }'
  chicago: Mahnken, Rolf, and Hendrik Westermann. “Construction of A-Stable Explicit
    Last-Stage Diagonal Implicit Runge–Kutta (ELDIRK) Methods.” <i>Computational Mechanics</i>,
    2024. <a href="https://doi.org/10.1007/s00466-024-02442-y">https://doi.org/10.1007/s00466-024-02442-y</a>.
  ieee: 'R. Mahnken and H. Westermann, “Construction of A-stable explicit last-stage
    diagonal implicit Runge–Kutta (ELDIRK) methods,” <i>Computational Mechanics</i>,
    2024, doi: <a href="https://doi.org/10.1007/s00466-024-02442-y">10.1007/s00466-024-02442-y</a>.'
  mla: Mahnken, Rolf, and Hendrik Westermann. “Construction of A-Stable Explicit Last-Stage
    Diagonal Implicit Runge–Kutta (ELDIRK) Methods.” <i>Computational Mechanics</i>,
    Springer Science and Business Media LLC, 2024, doi:<a href="https://doi.org/10.1007/s00466-024-02442-y">10.1007/s00466-024-02442-y</a>.
  short: R. Mahnken, H. Westermann, Computational Mechanics (2024).
date_created: 2024-03-03T13:23:28Z
date_updated: 2024-03-19T12:14:07Z
department:
- _id: '154'
- _id: '321'
doi: 10.1007/s00466-024-02442-y
keyword:
- Applied Mathematics
- Computational Mathematics
- Computational Theory and Mathematics
- Mechanical Engineering
- Ocean Engineering
- Computational Mechanics
language:
- iso: eng
publication: Computational Mechanics
publication_identifier:
  issn:
  - 0178-7675
  - 1432-0924
publication_status: published
publisher: Springer Science and Business Media LLC
quality_controlled: '1'
status: public
title: Construction of A-stable explicit last-stage diagonal implicit Runge–Kutta
  (ELDIRK) methods
type: journal_article
user_id: '335'
year: '2024'
...
---
_id: '56212'
abstract:
- lang: eng
  text: <jats:title>Abstract</jats:title><jats:p>To increase the quality of computational
    results for heterogeneous materials like fiber‐reinforced composites with Prandtl–Reuss‐type
    material laws, goal‐oriented measures of the adaptive finite element method coupled
    to model adaptivity is established. The former is an adaptive mesh refinement
    on the macroscale, which allows to control the spatial discretization errors.
    The latter is an efficient combination of a numerically low cost nonuniform transformation
    field analysis (NTFA) and numerically high cost full‐field elasto‐plastic homogenization
    methods on the microscale. The present contribution deals with the application
    of the concept of downwind and upwind approximations to a goal‐oriented a posteriori
    error estimator based on duality techniques by means of reduced order homogenization
    schemes like NTFA, and with accuracy and numerical efficiency of the proposed
    goal‐oriented adaptive framework. NTFA consists of an offline phase and an online
    phase. During the offline phase, some relevant information of the micro system
    under consideration is precomputed allowing a reduced set of equations to be solved
    in the online phase. Thus, NTFA leads to a quite efficient homogenization method
    but less accurate compared to the full‐field homogenization method which is characterized
    with a high computational demand for accounting nonlinear microstructural mechanisms.
    Due to nonlinearities and time‐dependency of plasticity, the estimation of error
    transport and error generation are obtained with a backward‐in‐time dual method
    despite a high demand on memory capacity. In this contribution, the dual problem
    is solved with a forward‐in‐time dual method that allows estimating the full error
    during the resolution of the primal problem without the need for extra memory
    capacity. Several numerical examples illustrate the effectiveness of the proposed
    adaptive approach based on downwind and upwind approximations.</jats:p>
author:
- first_name: Arnold
  full_name: Tchomgue Simeu, Arnold
  id: '83075'
  last_name: Tchomgue Simeu
- first_name: Rolf
  full_name: Mahnken, Rolf
  last_name: Mahnken
citation:
  ama: Tchomgue Simeu A, Mahnken R. Mesh‐ and model adaptivity for NTFA and full‐field
    elasto‐plastic homogenization based on downwind and upwind approximations. <i>PAMM</i>.
    Published online 2024. doi:<a href="https://doi.org/10.1002/pamm.202400074">10.1002/pamm.202400074</a>
  apa: Tchomgue Simeu, A., &#38; Mahnken, R. (2024). Mesh‐ and model adaptivity for
    NTFA and full‐field elasto‐plastic homogenization based on downwind and upwind
    approximations. <i>PAMM</i>. <a href="https://doi.org/10.1002/pamm.202400074">https://doi.org/10.1002/pamm.202400074</a>
  bibtex: '@article{Tchomgue Simeu_Mahnken_2024, title={Mesh‐ and model adaptivity
    for NTFA and full‐field elasto‐plastic homogenization based on downwind and upwind
    approximations}, DOI={<a href="https://doi.org/10.1002/pamm.202400074">10.1002/pamm.202400074</a>},
    journal={PAMM}, publisher={Wiley}, author={Tchomgue Simeu, Arnold and Mahnken,
    Rolf}, year={2024} }'
  chicago: Tchomgue Simeu, Arnold, and Rolf Mahnken. “Mesh‐ and Model Adaptivity for
    NTFA and Full‐field Elasto‐plastic Homogenization Based on Downwind and Upwind
    Approximations.” <i>PAMM</i>, 2024. <a href="https://doi.org/10.1002/pamm.202400074">https://doi.org/10.1002/pamm.202400074</a>.
  ieee: 'A. Tchomgue Simeu and R. Mahnken, “Mesh‐ and model adaptivity for NTFA and
    full‐field elasto‐plastic homogenization based on downwind and upwind approximations,”
    <i>PAMM</i>, 2024, doi: <a href="https://doi.org/10.1002/pamm.202400074">10.1002/pamm.202400074</a>.'
  mla: Tchomgue Simeu, Arnold, and Rolf Mahnken. “Mesh‐ and Model Adaptivity for NTFA
    and Full‐field Elasto‐plastic Homogenization Based on Downwind and Upwind Approximations.”
    <i>PAMM</i>, Wiley, 2024, doi:<a href="https://doi.org/10.1002/pamm.202400074">10.1002/pamm.202400074</a>.
  short: A. Tchomgue Simeu, R. Mahnken, PAMM (2024).
date_created: 2024-09-23T11:23:21Z
date_updated: 2024-09-23T11:26:52Z
department:
- _id: '9'
- _id: '154'
- _id: '321'
doi: 10.1002/pamm.202400074
language:
- iso: eng
publication: PAMM
publication_identifier:
  issn:
  - 1617-7061
  - 1617-7061
publication_status: published
publisher: Wiley
quality_controlled: '1'
status: public
title: Mesh‐ and model adaptivity for NTFA and full‐field elasto‐plastic homogenization
  based on downwind and upwind approximations
type: journal_article
user_id: '85414'
year: '2024'
...
---
_id: '54281'
abstract:
- lang: eng
  text: <jats:title>Abstract</jats:title><jats:p>Polycarbonate (PC) is an amorphous
    polymer that is an extremely robust material with a high tenacity, and thus suitable
    for a lightweight construction with glass‐like transparency. Due to these advantageous
    properties, PC is often used in industry for example in medical devices, automotive
    headlamps, sporting equipment, electronics, and a variety of other products. PC
    is often subjected to uniaxial and biaxial loading conditions. Therefore, reliable
    material models have to take into account the various resulting experimental effects.
    For those reasons, we investigate PC specimens under uniaxial and biaxial loading
    by using different stretch rates and loading scenarios. In addition to that, we
    propose methods for optical measurement of local stretches to obtain the approximated
    local true stress. In future work, the displacement fields and the resulting reaction
    forces will be used for parameter identification of constitutive equations.</jats:p>
author:
- first_name: Ayoub
  full_name: Hamdoun, Ayoub
  id: '57708'
  last_name: Hamdoun
- first_name: Rolf
  full_name: Mahnken, Rolf
  id: '335'
  last_name: Mahnken
citation:
  ama: Hamdoun A, Mahnken R. Experimental investigations of uniaxial and biaxial cold
    stretching within PC‐films and bars using optical measurements. <i>PAMM</i>. Published
    online 2024. doi:<a href="https://doi.org/10.1002/pamm.202300114">10.1002/pamm.202300114</a>
  apa: Hamdoun, A., &#38; Mahnken, R. (2024). Experimental investigations of uniaxial
    and biaxial cold stretching within PC‐films and bars using optical measurements.
    <i>PAMM</i>. <a href="https://doi.org/10.1002/pamm.202300114">https://doi.org/10.1002/pamm.202300114</a>
  bibtex: '@article{Hamdoun_Mahnken_2024, title={Experimental investigations of uniaxial
    and biaxial cold stretching within PC‐films and bars using optical measurements},
    DOI={<a href="https://doi.org/10.1002/pamm.202300114">10.1002/pamm.202300114</a>},
    journal={PAMM}, publisher={Wiley}, author={Hamdoun, Ayoub and Mahnken, Rolf},
    year={2024} }'
  chicago: Hamdoun, Ayoub, and Rolf Mahnken. “Experimental Investigations of Uniaxial
    and Biaxial Cold Stretching within PC‐films and Bars Using Optical Measurements.”
    <i>PAMM</i>, 2024. <a href="https://doi.org/10.1002/pamm.202300114">https://doi.org/10.1002/pamm.202300114</a>.
  ieee: 'A. Hamdoun and R. Mahnken, “Experimental investigations of uniaxial and biaxial
    cold stretching within PC‐films and bars using optical measurements,” <i>PAMM</i>,
    2024, doi: <a href="https://doi.org/10.1002/pamm.202300114">10.1002/pamm.202300114</a>.'
  mla: Hamdoun, Ayoub, and Rolf Mahnken. “Experimental Investigations of Uniaxial
    and Biaxial Cold Stretching within PC‐films and Bars Using Optical Measurements.”
    <i>PAMM</i>, Wiley, 2024, doi:<a href="https://doi.org/10.1002/pamm.202300114">10.1002/pamm.202300114</a>.
  short: A. Hamdoun, R. Mahnken, PAMM (2024).
date_created: 2024-05-14T09:06:26Z
date_updated: 2024-09-26T11:25:10Z
department:
- _id: '9'
- _id: '154'
doi: 10.1002/pamm.202300114
language:
- iso: eng
publication: PAMM
publication_identifier:
  issn:
  - 1617-7061
  - 1617-7061
publication_status: published
publisher: Wiley
status: public
title: Experimental investigations of uniaxial and biaxial cold stretching within
  PC‐films and bars using optical measurements
type: journal_article
user_id: '57708'
year: '2024'
...
---
_id: '54279'
article_number: '126981'
author:
- first_name: Ayoub
  full_name: Hamdoun, Ayoub
  id: '57708'
  last_name: Hamdoun
- first_name: Rolf
  full_name: Mahnken, Rolf
  id: '335'
  last_name: Mahnken
citation:
  ama: Hamdoun A, Mahnken R. Uniaxial and biaxial experimental investigation of glassy
    polymers. <i>Polymer</i>. 2024;299. doi:<a href="https://doi.org/10.1016/j.polymer.2024.126981">10.1016/j.polymer.2024.126981</a>
  apa: Hamdoun, A., &#38; Mahnken, R. (2024). Uniaxial and biaxial experimental investigation
    of glassy polymers. <i>Polymer</i>, <i>299</i>, Article 126981. <a href="https://doi.org/10.1016/j.polymer.2024.126981">https://doi.org/10.1016/j.polymer.2024.126981</a>
  bibtex: '@article{Hamdoun_Mahnken_2024, title={Uniaxial and biaxial experimental
    investigation of glassy polymers}, volume={299}, DOI={<a href="https://doi.org/10.1016/j.polymer.2024.126981">10.1016/j.polymer.2024.126981</a>},
    number={126981}, journal={Polymer}, publisher={Elsevier BV}, author={Hamdoun,
    Ayoub and Mahnken, Rolf}, year={2024} }'
  chicago: Hamdoun, Ayoub, and Rolf Mahnken. “Uniaxial and Biaxial Experimental Investigation
    of Glassy Polymers.” <i>Polymer</i> 299 (2024). <a href="https://doi.org/10.1016/j.polymer.2024.126981">https://doi.org/10.1016/j.polymer.2024.126981</a>.
  ieee: 'A. Hamdoun and R. Mahnken, “Uniaxial and biaxial experimental investigation
    of glassy polymers,” <i>Polymer</i>, vol. 299, Art. no. 126981, 2024, doi: <a
    href="https://doi.org/10.1016/j.polymer.2024.126981">10.1016/j.polymer.2024.126981</a>.'
  mla: Hamdoun, Ayoub, and Rolf Mahnken. “Uniaxial and Biaxial Experimental Investigation
    of Glassy Polymers.” <i>Polymer</i>, vol. 299, 126981, Elsevier BV, 2024, doi:<a
    href="https://doi.org/10.1016/j.polymer.2024.126981">10.1016/j.polymer.2024.126981</a>.
  short: A. Hamdoun, R. Mahnken, Polymer 299 (2024).
date_created: 2024-05-14T09:05:05Z
date_updated: 2024-09-26T11:25:29Z
department:
- _id: '9'
- _id: '154'
- _id: '321'
doi: 10.1016/j.polymer.2024.126981
intvolume: '       299'
language:
- iso: eng
publication: Polymer
publication_identifier:
  issn:
  - 0032-3861
publication_status: published
publisher: Elsevier BV
quality_controlled: '1'
status: public
title: Uniaxial and biaxial experimental investigation of glassy polymers
type: journal_article
user_id: '57708'
volume: 299
year: '2024'
...
---
_id: '54280'
abstract:
- lang: eng
  text: <jats:title>Abstract</jats:title><jats:p>Cold forming of polycarbonate films
    results in the formation of shear bands in the necking zone. The numerical results
    obtained from standard viscoplastic material models exhibit mesh size dependency,
    requiring mathematical regularization. For this purpose, we present in this work
    a large deformation gradient theory for a viscoplastic isotropic material model
    published before. We extend our model to a micromorphic model by introducing a
    new micromorphic variable as an additional degree of freedom along with its first
    gradient. This variable represents a microequivalent plastic strain. The relation
    between the macroequivalent plastic strain and the micromorphic variable is accomplished
    by a micromorphic coupling modulus. This coupling forces proximity between the
    macro- and microvariables, leading to the targeted regularization effect. The
    micromorphic model is implemented as a three-dimensional initial boundary value
    problem in an in-house finite element tool. The analysis is performed for both
    uniaxial and biaxial specimens. The provided numerical examples show the ability
    of our model to regularize shear bands within the specimens and address the issue
    of localization.</jats:p>
author:
- first_name: Ayoub
  full_name: Hamdoun, Ayoub
  id: '57708'
  last_name: Hamdoun
- first_name: Rolf
  full_name: Mahnken, Rolf
  id: '335'
  last_name: Mahnken
citation:
  ama: Hamdoun A, Mahnken R. A large deformation gradient theory for glassy polymers
    by means of micromorphic regularization. <i>Archive of Applied Mechanics</i>.
    2024;94(5):1221-1242. doi:<a href="https://doi.org/10.1007/s00419-024-02570-0">10.1007/s00419-024-02570-0</a>
  apa: Hamdoun, A., &#38; Mahnken, R. (2024). A large deformation gradient theory
    for glassy polymers by means of micromorphic regularization. <i>Archive of Applied
    Mechanics</i>, <i>94</i>(5), 1221–1242. <a href="https://doi.org/10.1007/s00419-024-02570-0">https://doi.org/10.1007/s00419-024-02570-0</a>
  bibtex: '@article{Hamdoun_Mahnken_2024, title={A large deformation gradient theory
    for glassy polymers by means of micromorphic regularization}, volume={94}, DOI={<a
    href="https://doi.org/10.1007/s00419-024-02570-0">10.1007/s00419-024-02570-0</a>},
    number={5}, journal={Archive of Applied Mechanics}, publisher={Springer Science
    and Business Media LLC}, author={Hamdoun, Ayoub and Mahnken, Rolf}, year={2024},
    pages={1221–1242} }'
  chicago: 'Hamdoun, Ayoub, and Rolf Mahnken. “A Large Deformation Gradient Theory
    for Glassy Polymers by Means of Micromorphic Regularization.” <i>Archive of Applied
    Mechanics</i> 94, no. 5 (2024): 1221–42. <a href="https://doi.org/10.1007/s00419-024-02570-0">https://doi.org/10.1007/s00419-024-02570-0</a>.'
  ieee: 'A. Hamdoun and R. Mahnken, “A large deformation gradient theory for glassy
    polymers by means of micromorphic regularization,” <i>Archive of Applied Mechanics</i>,
    vol. 94, no. 5, pp. 1221–1242, 2024, doi: <a href="https://doi.org/10.1007/s00419-024-02570-0">10.1007/s00419-024-02570-0</a>.'
  mla: Hamdoun, Ayoub, and Rolf Mahnken. “A Large Deformation Gradient Theory for
    Glassy Polymers by Means of Micromorphic Regularization.” <i>Archive of Applied
    Mechanics</i>, vol. 94, no. 5, Springer Science and Business Media LLC, 2024,
    pp. 1221–42, doi:<a href="https://doi.org/10.1007/s00419-024-02570-0">10.1007/s00419-024-02570-0</a>.
  short: A. Hamdoun, R. Mahnken, Archive of Applied Mechanics 94 (2024) 1221–1242.
date_created: 2024-05-14T09:05:40Z
date_updated: 2024-09-26T11:25:44Z
department:
- _id: '9'
- _id: '154'
- _id: '321'
doi: 10.1007/s00419-024-02570-0
intvolume: '        94'
issue: '5'
language:
- iso: eng
page: 1221-1242
publication: Archive of Applied Mechanics
publication_identifier:
  issn:
  - 0939-1533
  - 1432-0681
publication_status: published
publisher: Springer Science and Business Media LLC
quality_controlled: '1'
status: public
title: A large deformation gradient theory for glassy polymers by means of micromorphic
  regularization
type: journal_article
user_id: '57708'
volume: 94
year: '2024'
...
---
_id: '56721'
article_number: '117277'
author:
- first_name: Rolf
  full_name: Mahnken, Rolf
  last_name: Mahnken
- first_name: Arnold
  full_name: Tchomgue Simeu, Arnold
  id: '83075'
  last_name: Tchomgue Simeu
citation:
  ama: Mahnken R, Tchomgue Simeu A. Downwind and upwind approximations for primal
    and dual problems of elasto-plasticity with Prandtl–Reuss type material laws.
    <i>Computer Methods in Applied Mechanics and Engineering</i>. 2024;432. doi:<a
    href="https://doi.org/10.1016/j.cma.2024.117277">10.1016/j.cma.2024.117277</a>
  apa: Mahnken, R., &#38; Tchomgue Simeu, A. (2024). Downwind and upwind approximations
    for primal and dual problems of elasto-plasticity with Prandtl–Reuss type material
    laws. <i>Computer Methods in Applied Mechanics and Engineering</i>, <i>432</i>,
    Article 117277. <a href="https://doi.org/10.1016/j.cma.2024.117277">https://doi.org/10.1016/j.cma.2024.117277</a>
  bibtex: '@article{Mahnken_Tchomgue Simeu_2024, title={Downwind and upwind approximations
    for primal and dual problems of elasto-plasticity with Prandtl–Reuss type material
    laws}, volume={432}, DOI={<a href="https://doi.org/10.1016/j.cma.2024.117277">10.1016/j.cma.2024.117277</a>},
    number={117277}, journal={Computer Methods in Applied Mechanics and Engineering},
    publisher={Elsevier BV}, author={Mahnken, Rolf and Tchomgue Simeu, Arnold}, year={2024}
    }'
  chicago: Mahnken, Rolf, and Arnold Tchomgue Simeu. “Downwind and Upwind Approximations
    for Primal and Dual Problems of Elasto-Plasticity with Prandtl–Reuss Type Material
    Laws.” <i>Computer Methods in Applied Mechanics and Engineering</i> 432 (2024).
    <a href="https://doi.org/10.1016/j.cma.2024.117277">https://doi.org/10.1016/j.cma.2024.117277</a>.
  ieee: 'R. Mahnken and A. Tchomgue Simeu, “Downwind and upwind approximations for
    primal and dual problems of elasto-plasticity with Prandtl–Reuss type material
    laws,” <i>Computer Methods in Applied Mechanics and Engineering</i>, vol. 432,
    Art. no. 117277, 2024, doi: <a href="https://doi.org/10.1016/j.cma.2024.117277">10.1016/j.cma.2024.117277</a>.'
  mla: Mahnken, Rolf, and Arnold Tchomgue Simeu. “Downwind and Upwind Approximations
    for Primal and Dual Problems of Elasto-Plasticity with Prandtl–Reuss Type Material
    Laws.” <i>Computer Methods in Applied Mechanics and Engineering</i>, vol. 432,
    117277, Elsevier BV, 2024, doi:<a href="https://doi.org/10.1016/j.cma.2024.117277">10.1016/j.cma.2024.117277</a>.
  short: R. Mahnken, A. Tchomgue Simeu, Computer Methods in Applied Mechanics and
    Engineering 432 (2024).
date_created: 2024-10-22T10:44:02Z
date_updated: 2024-11-08T08:54:41Z
department:
- _id: '321'
- _id: '154'
- _id: '321'
doi: 10.1016/j.cma.2024.117277
intvolume: '       432'
language:
- iso: eng
project:
- _id: '1218'
  grant_number: 'Geschäftszeichen: MA 1979/30-2'
  name: Hier20 - Zielorientierte Adaptivität für nichtlineare Homogenisierungen mittels
    hierarchischer Modelle
publication: Computer Methods in Applied Mechanics and Engineering
publication_identifier:
  issn:
  - 0045-7825
publication_status: published
publisher: Elsevier BV
quality_controlled: '1'
status: public
title: Downwind and upwind approximations for primal and dual problems of elasto-plasticity
  with Prandtl–Reuss type material laws
type: journal_article
user_id: '85414'
volume: 432
year: '2024'
...
---
_id: '48464'
abstract:
- lang: eng
  text: <jats:title>Abstract</jats:title><jats:p>Initial value problems can be solved
    efficiently by means of Runge–Kutta algorithms with adaptive step size control.
    Diagonally implicit Runge–Kutta (DIRK) methods are the most popular class among
    the diverse family of Runge–Kutta algorithms. In this paper, the novel class of
    low‐order explicit last‐stage diagonally implicit Runge–Kutta (ELDIRK) methods
    are explored, which combine implicit schemes with an additional explicit evaluation
    as an explicit last stage. ELDIRK Butcher tableaus are used to control embedded
    RK methods to obtain solutions of different orders. The lower‐order solution is
    obtained by classical implicit RK stages and the higher‐order solution is obtained
    by additional explicit evaluation. As a result, a significant reduction in computational
    cost is achieved by skipping the iterative solution of nonlinear systems for the
    additional step. The examination of the heat problem and the use of the innovative
    Butcher tableau in the finite‐element method are the main contributions of this
    work. Thus, it is possible to establish adaptive step size control for the new
    low‐order embedded methods based on an empirical method for error estimation.
    Two‐dimensional simulations are used to show an appropriate algorithm for the
    ELDIRK schemes. The new Runge–Kutta schemes' predictions of higher‐order convergence
    are confirmed, and their successful outcomes are illustrated.</jats:p>
author:
- first_name: Hendrik
  full_name: Westermann, Hendrik
  id: '60816'
  last_name: Westermann
  orcid: 0000-0002-5034-9708
- first_name: Rolf
  full_name: Mahnken, Rolf
  id: '335'
  last_name: Mahnken
citation:
  ama: Westermann H, Mahnken R. Numerical investigations of new low‐order explicit
    last stage diagonal implicit Runge–Kutta schemes with the finite‐element method.
    <i>PAMM</i>. 2023;23(2). doi:<a href="https://doi.org/10.1002/pamm.202300071">10.1002/pamm.202300071</a>
  apa: Westermann, H., &#38; Mahnken, R. (2023). Numerical investigations of new low‐order
    explicit last stage diagonal implicit Runge–Kutta schemes with the finite‐element
    method. <i>PAMM</i>, <i>23</i>(2). <a href="https://doi.org/10.1002/pamm.202300071">https://doi.org/10.1002/pamm.202300071</a>
  bibtex: '@article{Westermann_Mahnken_2023, title={Numerical investigations of new
    low‐order explicit last stage diagonal implicit Runge–Kutta schemes with the finite‐element
    method}, volume={23}, DOI={<a href="https://doi.org/10.1002/pamm.202300071">10.1002/pamm.202300071</a>},
    number={2}, journal={PAMM}, publisher={Wiley}, author={Westermann, Hendrik and
    Mahnken, Rolf}, year={2023} }'
  chicago: Westermann, Hendrik, and Rolf Mahnken. “Numerical Investigations of New
    Low‐order Explicit Last Stage Diagonal Implicit Runge–Kutta Schemes with the Finite‐element
    Method.” <i>PAMM</i> 23, no. 2 (2023). <a href="https://doi.org/10.1002/pamm.202300071">https://doi.org/10.1002/pamm.202300071</a>.
  ieee: 'H. Westermann and R. Mahnken, “Numerical investigations of new low‐order
    explicit last stage diagonal implicit Runge–Kutta schemes with the finite‐element
    method,” <i>PAMM</i>, vol. 23, no. 2, 2023, doi: <a href="https://doi.org/10.1002/pamm.202300071">10.1002/pamm.202300071</a>.'
  mla: Westermann, Hendrik, and Rolf Mahnken. “Numerical Investigations of New Low‐order
    Explicit Last Stage Diagonal Implicit Runge–Kutta Schemes with the Finite‐element
    Method.” <i>PAMM</i>, vol. 23, no. 2, Wiley, 2023, doi:<a href="https://doi.org/10.1002/pamm.202300071">10.1002/pamm.202300071</a>.
  short: H. Westermann, R. Mahnken, PAMM 23 (2023).
date_created: 2023-10-25T10:46:57Z
date_updated: 2023-11-07T14:34:44Z
department:
- _id: '9'
- _id: '154'
- _id: '321'
doi: 10.1002/pamm.202300071
intvolume: '        23'
issue: '2'
keyword:
- Electrical and Electronic Engineering
- Atomic and Molecular Physics
- and Optics
language:
- iso: eng
publication: PAMM
publication_identifier:
  issn:
  - 1617-7061
  - 1617-7061
publication_status: published
publisher: Wiley
quality_controlled: '1'
status: public
title: Numerical investigations of new low‐order explicit last stage diagonal implicit
  Runge–Kutta schemes with the finite‐element method
type: journal_article
user_id: '335'
volume: 23
year: '2023'
...
---
_id: '48465'
article_number: '116545'
author:
- first_name: Hendrik
  full_name: Westermann, Hendrik
  id: '60816'
  last_name: Westermann
  orcid: 0000-0002-5034-9708
- first_name: Rolf
  full_name: Mahnken, Rolf
  id: '335'
  last_name: Mahnken
citation:
  ama: Westermann H, Mahnken R. On the accuracy, stability and computational efficiency
    of explicit last-stage diagonally implicit Runge–Kutta methods (ELDIRK) for the
    adaptive solution of phase-field problems. <i>Computer Methods in Applied Mechanics
    and Engineering</i>. 2023;418. doi:<a href="https://doi.org/10.1016/j.cma.2023.116545">10.1016/j.cma.2023.116545</a>
  apa: Westermann, H., &#38; Mahnken, R. (2023). On the accuracy, stability and computational
    efficiency of explicit last-stage diagonally implicit Runge–Kutta methods (ELDIRK)
    for the adaptive solution of phase-field problems. <i>Computer Methods in Applied
    Mechanics and Engineering</i>, <i>418</i>, Article 116545. <a href="https://doi.org/10.1016/j.cma.2023.116545">https://doi.org/10.1016/j.cma.2023.116545</a>
  bibtex: '@article{Westermann_Mahnken_2023, title={On the accuracy, stability and
    computational efficiency of explicit last-stage diagonally implicit Runge–Kutta
    methods (ELDIRK) for the adaptive solution of phase-field problems}, volume={418},
    DOI={<a href="https://doi.org/10.1016/j.cma.2023.116545">10.1016/j.cma.2023.116545</a>},
    number={116545}, journal={Computer Methods in Applied Mechanics and Engineering},
    publisher={Elsevier BV}, author={Westermann, Hendrik and Mahnken, Rolf}, year={2023}
    }'
  chicago: Westermann, Hendrik, and Rolf Mahnken. “On the Accuracy, Stability and
    Computational Efficiency of Explicit Last-Stage Diagonally Implicit Runge–Kutta
    Methods (ELDIRK) for the Adaptive Solution of Phase-Field Problems.” <i>Computer
    Methods in Applied Mechanics and Engineering</i> 418 (2023). <a href="https://doi.org/10.1016/j.cma.2023.116545">https://doi.org/10.1016/j.cma.2023.116545</a>.
  ieee: 'H. Westermann and R. Mahnken, “On the accuracy, stability and computational
    efficiency of explicit last-stage diagonally implicit Runge–Kutta methods (ELDIRK)
    for the adaptive solution of phase-field problems,” <i>Computer Methods in Applied
    Mechanics and Engineering</i>, vol. 418, Art. no. 116545, 2023, doi: <a href="https://doi.org/10.1016/j.cma.2023.116545">10.1016/j.cma.2023.116545</a>.'
  mla: Westermann, Hendrik, and Rolf Mahnken. “On the Accuracy, Stability and Computational
    Efficiency of Explicit Last-Stage Diagonally Implicit Runge–Kutta Methods (ELDIRK)
    for the Adaptive Solution of Phase-Field Problems.” <i>Computer Methods in Applied
    Mechanics and Engineering</i>, vol. 418, 116545, Elsevier BV, 2023, doi:<a href="https://doi.org/10.1016/j.cma.2023.116545">10.1016/j.cma.2023.116545</a>.
  short: H. Westermann, R. Mahnken, Computer Methods in Applied Mechanics and Engineering
    418 (2023).
date_created: 2023-10-25T10:47:23Z
date_updated: 2023-11-07T14:34:56Z
department:
- _id: '9'
- _id: '154'
- _id: '321'
doi: 10.1016/j.cma.2023.116545
intvolume: '       418'
keyword:
- Computer Science Applications
- General Physics and Astronomy
- Mechanical Engineering
- Mechanics of Materials
- Computational Mechanics
language:
- iso: eng
publication: Computer Methods in Applied Mechanics and Engineering
publication_identifier:
  issn:
  - 0045-7825
publication_status: published
publisher: Elsevier BV
quality_controlled: '1'
status: public
title: On the accuracy, stability and computational efficiency of explicit last-stage
  diagonally implicit Runge–Kutta methods (ELDIRK) for the adaptive solution of phase-field
  problems
type: journal_article
user_id: '335'
volume: 418
year: '2023'
...
---
_id: '48673'
article_number: '107160'
author:
- first_name: Peter
  full_name: Lenz, Peter
  last_name: Lenz
- first_name: Phil
  full_name: Kreutzheide, Phil
  last_name: Kreutzheide
- first_name: Rolf
  full_name: Mahnken, Rolf
  id: '335'
  last_name: Mahnken
citation:
  ama: Lenz P, Kreutzheide P, Mahnken R. Multiphase elasto-plastic mean-field homogenisation
    and its consistent linearisation. <i>Computers &#38;amp; Structures</i>. 2023;290.
    doi:<a href="https://doi.org/10.1016/j.compstruc.2023.107160">10.1016/j.compstruc.2023.107160</a>
  apa: Lenz, P., Kreutzheide, P., &#38; Mahnken, R. (2023). Multiphase elasto-plastic
    mean-field homogenisation and its consistent linearisation. <i>Computers &#38;amp;
    Structures</i>, <i>290</i>, Article 107160. <a href="https://doi.org/10.1016/j.compstruc.2023.107160">https://doi.org/10.1016/j.compstruc.2023.107160</a>
  bibtex: '@article{Lenz_Kreutzheide_Mahnken_2023, title={Multiphase elasto-plastic
    mean-field homogenisation and its consistent linearisation}, volume={290}, DOI={<a
    href="https://doi.org/10.1016/j.compstruc.2023.107160">10.1016/j.compstruc.2023.107160</a>},
    number={107160}, journal={Computers &#38;amp; Structures}, publisher={Elsevier
    BV}, author={Lenz, Peter and Kreutzheide, Phil and Mahnken, Rolf}, year={2023}
    }'
  chicago: Lenz, Peter, Phil Kreutzheide, and Rolf Mahnken. “Multiphase Elasto-Plastic
    Mean-Field Homogenisation and Its Consistent Linearisation.” <i>Computers &#38;amp;
    Structures</i> 290 (2023). <a href="https://doi.org/10.1016/j.compstruc.2023.107160">https://doi.org/10.1016/j.compstruc.2023.107160</a>.
  ieee: 'P. Lenz, P. Kreutzheide, and R. Mahnken, “Multiphase elasto-plastic mean-field
    homogenisation and its consistent linearisation,” <i>Computers &#38;amp; Structures</i>,
    vol. 290, Art. no. 107160, 2023, doi: <a href="https://doi.org/10.1016/j.compstruc.2023.107160">10.1016/j.compstruc.2023.107160</a>.'
  mla: Lenz, Peter, et al. “Multiphase Elasto-Plastic Mean-Field Homogenisation and
    Its Consistent Linearisation.” <i>Computers &#38;amp; Structures</i>, vol. 290,
    107160, Elsevier BV, 2023, doi:<a href="https://doi.org/10.1016/j.compstruc.2023.107160">10.1016/j.compstruc.2023.107160</a>.
  short: P. Lenz, P. Kreutzheide, R. Mahnken, Computers &#38;amp; Structures 290 (2023).
date_created: 2023-11-07T14:33:33Z
date_updated: 2023-11-07T14:35:05Z
department:
- _id: '9'
- _id: '154'
- _id: '321'
doi: 10.1016/j.compstruc.2023.107160
intvolume: '       290'
keyword:
- Computer Science Applications
- Mechanical Engineering
- General Materials Science
- Modeling and Simulation
- Civil and Structural Engineering
language:
- iso: eng
publication: Computers &amp; Structures
publication_identifier:
  issn:
  - 0045-7949
publication_status: published
publisher: Elsevier BV
quality_controlled: '1'
status: public
title: Multiphase elasto-plastic mean-field homogenisation and its consistent linearisation
type: journal_article
user_id: '335'
volume: 290
year: '2023'
...
---
_id: '49866'
abstract:
- lang: eng
  text: <jats:title>Abstract</jats:title><jats:p>The use of heterogeneous materials,
    such as composites with Prandtl‐Reuss‐type material laws, has increased in industrial
    praxis, making finite element modeling with homogenization techniques a well‐accepted
    tool. These methods are particularly advantageous to account for microstructural
    mechanisms which can be related to nonlinearities and time‐dependency due to elasto‐plasticity
    behavior. However, their advantages are diminished by increasing computational
    demand. The present contribution deals with the balance of accuracy and numerical
    efficiency of nonlinear homogenization associated with a framework of goal‐oriented
    adaptivity, which takes into account error accumulation over time. To this end,
    model adaptivity of homogenization methods is coupled to mesh adaptivity on the
    macro scale. Our new proposed adaptive procedure is driven by a goal‐oriented
    a posteriori error estimator based on duality techniques using downwind and upwind
    approximations. Due to nonlinearities and time‐dependency of the plasticity, the
    estimation of error transport and error generation is obtained with a backward‐in‐time
    dual method despite a high demand on memory capacity. In this contribution, the
    dual problem is solved with a forward‐in‐time dual method that allows estimating
    the full error during the resolution of the primal problem without the need for
    extra memory capacity. Finally, a numerical example illustrates the effectiveness
    of the proposed adaptive approach.</jats:p>
author:
- first_name: Arnold
  full_name: Tchomgue Simeu, Arnold
  id: '83075'
  last_name: Tchomgue Simeu
- first_name: Rolf
  full_name: Mahnken, Rolf
  id: '335'
  last_name: Mahnken
citation:
  ama: Tchomgue Simeu A, Mahnken R. Downwind and upwind approximations for mesh and
    model adaptivity of elasto‐plastic composites. <i>PAMM</i>. Published online 2023.
    doi:<a href="https://doi.org/10.1002/pamm.202300136">10.1002/pamm.202300136</a>
  apa: Tchomgue Simeu, A., &#38; Mahnken, R. (2023). Downwind and upwind approximations
    for mesh and model adaptivity of elasto‐plastic composites. <i>PAMM</i>. <a href="https://doi.org/10.1002/pamm.202300136">https://doi.org/10.1002/pamm.202300136</a>
  bibtex: '@article{Tchomgue Simeu_Mahnken_2023, title={Downwind and upwind approximations
    for mesh and model adaptivity of elasto‐plastic composites}, DOI={<a href="https://doi.org/10.1002/pamm.202300136">10.1002/pamm.202300136</a>},
    journal={PAMM}, publisher={Wiley}, author={Tchomgue Simeu, Arnold and Mahnken,
    Rolf}, year={2023} }'
  chicago: Tchomgue Simeu, Arnold, and Rolf Mahnken. “Downwind and Upwind Approximations
    for Mesh and Model Adaptivity of Elasto‐plastic Composites.” <i>PAMM</i>, 2023.
    <a href="https://doi.org/10.1002/pamm.202300136">https://doi.org/10.1002/pamm.202300136</a>.
  ieee: 'A. Tchomgue Simeu and R. Mahnken, “Downwind and upwind approximations for
    mesh and model adaptivity of elasto‐plastic composites,” <i>PAMM</i>, 2023, doi:
    <a href="https://doi.org/10.1002/pamm.202300136">10.1002/pamm.202300136</a>.'
  mla: Tchomgue Simeu, Arnold, and Rolf Mahnken. “Downwind and Upwind Approximations
    for Mesh and Model Adaptivity of Elasto‐plastic Composites.” <i>PAMM</i>, Wiley,
    2023, doi:<a href="https://doi.org/10.1002/pamm.202300136">10.1002/pamm.202300136</a>.
  short: A. Tchomgue Simeu, R. Mahnken, PAMM (2023).
date_created: 2023-12-19T12:20:05Z
date_updated: 2023-12-19T12:20:51Z
department:
- _id: '9'
- _id: '154'
- _id: '321'
doi: 10.1002/pamm.202300136
keyword:
- Electrical and Electronic Engineering
- Atomic and Molecular Physics
- and Optics
language:
- iso: eng
publication: PAMM
publication_identifier:
  issn:
  - 1617-7061
  - 1617-7061
publication_status: published
publisher: Wiley
quality_controlled: '1'
status: public
title: Downwind and upwind approximations for mesh and model adaptivity of elasto‐plastic
  composites
type: journal_article
user_id: '335'
year: '2023'
...
---
_id: '52219'
abstract:
- lang: eng
  text: <jats:title>Abstract</jats:title><jats:p>Cold‐box sand (CBS) belongs to the
    granular materials and consists of sand and a binder. The behavior of CBS is simulated
    with a micropolar model, whereby the additional degree of freedom of the model
    describes the rotation of the sand grains. The model is used to generate a shear
    band under pressure for three different meshes, where the force‐displacement curves
    of the three meshes converge so that no mesh dependence occurs. Another requirement
    of the model is the consideration of asymmetric behavior for compression and tension.
    Due to the additional degree of freedom the implicit implementation of the micropolar
    continuum is very time‐consuming. Therefore, an explicit implementation is considered
    as an alternative possibility. This paper compares the advantages and disadvantages
    of both methods and the results for both calculations.</jats:p>
author:
- first_name: Alexander
  full_name: Börger, Alexander
  last_name: Börger
- first_name: Rolf
  full_name: Mahnken, Rolf
  id: '335'
  last_name: Mahnken
citation:
  ama: Börger A, Mahnken R. A micropolar model accounting for asymmetric behavior
    of cold‐box sand in relation to tensile and compression tests. <i>PAMM</i>. Published
    online 2023. doi:<a href="https://doi.org/10.1002/pamm.202300126">10.1002/pamm.202300126</a>
  apa: Börger, A., &#38; Mahnken, R. (2023). A micropolar model accounting for asymmetric
    behavior of cold‐box sand in relation to tensile and compression tests. <i>PAMM</i>.
    <a href="https://doi.org/10.1002/pamm.202300126">https://doi.org/10.1002/pamm.202300126</a>
  bibtex: '@article{Börger_Mahnken_2023, title={A micropolar model accounting for
    asymmetric behavior of cold‐box sand in relation to tensile and compression tests},
    DOI={<a href="https://doi.org/10.1002/pamm.202300126">10.1002/pamm.202300126</a>},
    journal={PAMM}, publisher={Wiley}, author={Börger, Alexander and Mahnken, Rolf},
    year={2023} }'
  chicago: Börger, Alexander, and Rolf Mahnken. “A Micropolar Model Accounting for
    Asymmetric Behavior of Cold‐box Sand in Relation to Tensile and Compression Tests.”
    <i>PAMM</i>, 2023. <a href="https://doi.org/10.1002/pamm.202300126">https://doi.org/10.1002/pamm.202300126</a>.
  ieee: 'A. Börger and R. Mahnken, “A micropolar model accounting for asymmetric behavior
    of cold‐box sand in relation to tensile and compression tests,” <i>PAMM</i>, 2023,
    doi: <a href="https://doi.org/10.1002/pamm.202300126">10.1002/pamm.202300126</a>.'
  mla: Börger, Alexander, and Rolf Mahnken. “A Micropolar Model Accounting for Asymmetric
    Behavior of Cold‐box Sand in Relation to Tensile and Compression Tests.” <i>PAMM</i>,
    Wiley, 2023, doi:<a href="https://doi.org/10.1002/pamm.202300126">10.1002/pamm.202300126</a>.
  short: A. Börger, R. Mahnken, PAMM (2023).
date_created: 2024-02-29T13:59:12Z
date_updated: 2024-02-29T13:59:31Z
department:
- _id: '9'
- _id: '154'
- _id: '321'
doi: 10.1002/pamm.202300126
keyword:
- Electrical and Electronic Engineering
- Atomic and Molecular Physics
- and Optics
language:
- iso: eng
publication: PAMM
publication_identifier:
  issn:
  - 1617-7061
  - 1617-7061
publication_status: published
publisher: Wiley
quality_controlled: '1'
status: public
title: A micropolar model accounting for asymmetric behavior of cold‐box sand in relation
  to tensile and compression tests
type: journal_article
user_id: '335'
year: '2023'
...
---
_id: '52649'
author:
- first_name: Eduard
  full_name: Penner, Eduard
  last_name: Penner
citation:
  ama: Penner E. <i>Polymorphic Uncertainty in Constitutive Modeling of Polymer Composites
    at Different Scales</i>. Shaker Verlag; 2023. doi:<a href="https://doi.org/10.2370/9783844093322">10.2370/9783844093322</a>
  apa: Penner, E. (2023). <i>Polymorphic uncertainty in constitutive modeling of polymer
    composites at different scales</i>. Shaker Verlag. <a href="https://doi.org/10.2370/9783844093322">https://doi.org/10.2370/9783844093322</a>
  bibtex: '@book{Penner_2023, title={Polymorphic uncertainty in constitutive modeling
    of polymer composites at different scales}, DOI={<a href="https://doi.org/10.2370/9783844093322">10.2370/9783844093322</a>},
    publisher={Shaker Verlag}, author={Penner, Eduard}, year={2023} }'
  chicago: Penner, Eduard. <i>Polymorphic Uncertainty in Constitutive Modeling of
    Polymer Composites at Different Scales</i>. Shaker Verlag, 2023. <a href="https://doi.org/10.2370/9783844093322">https://doi.org/10.2370/9783844093322</a>.
  ieee: E. Penner, <i>Polymorphic uncertainty in constitutive modeling of polymer
    composites at different scales</i>. Shaker Verlag, 2023.
  mla: Penner, Eduard. <i>Polymorphic Uncertainty in Constitutive Modeling of Polymer
    Composites at Different Scales</i>. Shaker Verlag, 2023, doi:<a href="https://doi.org/10.2370/9783844093322">10.2370/9783844093322</a>.
  short: E. Penner, Polymorphic Uncertainty in Constitutive Modeling of Polymer Composites
    at Different Scales, Shaker Verlag, 2023.
date_created: 2024-03-19T12:59:06Z
date_updated: 2024-03-19T12:59:12Z
department:
- _id: '9'
- _id: '154'
- _id: '321'
doi: 10.2370/9783844093322
language:
- iso: eng
publication_identifier:
  unknown:
  - 978-3-8440-9332-2
publication_status: published
publisher: Shaker Verlag
status: public
supervisor:
- first_name: Rolf
  full_name: Mahnken, Rolf
  last_name: Mahnken
title: Polymorphic uncertainty in constitutive modeling of polymer composites at different
  scales
type: dissertation
user_id: '335'
year: '2023'
...
---
_id: '54282'
abstract:
- lang: eng
  text: <jats:title>Abstract</jats:title><jats:p>Stretching of polycarbonate films
    leads to the formation of shear bands in the necking zone [1]. Standard viscoplastic
    material models render mesh size dependent results, which requires a mathematical
    regularization. To this end, we present a finite strain gradient theory for a
    viscoplastic, isotropic material model where we extend the model presented in
    [2] to a micromorphic model by introducing a new micromorphic variable as an additional
    degree of freedom with its first gradient [3, 4]. The variable here has the meaning
    of a micro plastic strain, and is coupled with the macro plastic by a micro penalty
    term, forcing the macro‐plastic strain to be close to the micro‐plastic strain
    for the targeted shear band regularization effect. We have implemented the model
    equations as a three dimensional initial boundary value problem in an in house
    FE‐tool, to simulate different geometries with different thickness and to compare
    it the experimental tests. The analysis is performed for a uniaxial tensile geometry
    as well as for a biaxial tensile geometry. The numerical examples show the ability
    of the model to regularize the shear bands and solve the problem of localization.</jats:p>
author:
- first_name: Ayoub
  full_name: Hamdoun, Ayoub
  id: '57708'
  last_name: Hamdoun
- first_name: Rolf
  full_name: Mahnken, Rolf
  id: '335'
  last_name: Mahnken
citation:
  ama: Hamdoun A, Mahnken R. A finite strain gradient theory for viscoplasticity by
    means of micromorphic regularization. <i>PAMM</i>. 2023;22(1). doi:<a href="https://doi.org/10.1002/pamm.202200074">10.1002/pamm.202200074</a>
  apa: Hamdoun, A., &#38; Mahnken, R. (2023). A finite strain gradient theory for
    viscoplasticity by means of micromorphic regularization. <i>PAMM</i>, <i>22</i>(1).
    <a href="https://doi.org/10.1002/pamm.202200074">https://doi.org/10.1002/pamm.202200074</a>
  bibtex: '@article{Hamdoun_Mahnken_2023, title={A finite strain gradient theory for
    viscoplasticity by means of micromorphic regularization}, volume={22}, DOI={<a
    href="https://doi.org/10.1002/pamm.202200074">10.1002/pamm.202200074</a>}, number={1},
    journal={PAMM}, publisher={Wiley}, author={Hamdoun, Ayoub and Mahnken, Rolf},
    year={2023} }'
  chicago: Hamdoun, Ayoub, and Rolf Mahnken. “A Finite Strain Gradient Theory for
    Viscoplasticity by Means of Micromorphic Regularization.” <i>PAMM</i> 22, no.
    1 (2023). <a href="https://doi.org/10.1002/pamm.202200074">https://doi.org/10.1002/pamm.202200074</a>.
  ieee: 'A. Hamdoun and R. Mahnken, “A finite strain gradient theory for viscoplasticity
    by means of micromorphic regularization,” <i>PAMM</i>, vol. 22, no. 1, 2023, doi:
    <a href="https://doi.org/10.1002/pamm.202200074">10.1002/pamm.202200074</a>.'
  mla: Hamdoun, Ayoub, and Rolf Mahnken. “A Finite Strain Gradient Theory for Viscoplasticity
    by Means of Micromorphic Regularization.” <i>PAMM</i>, vol. 22, no. 1, Wiley,
    2023, doi:<a href="https://doi.org/10.1002/pamm.202200074">10.1002/pamm.202200074</a>.
  short: A. Hamdoun, R. Mahnken, PAMM 22 (2023).
date_created: 2024-05-14T09:06:38Z
date_updated: 2024-05-14T09:15:38Z
doi: 10.1002/pamm.202200074
intvolume: '        22'
issue: '1'
language:
- iso: eng
publication: PAMM
publication_identifier:
  issn:
  - 1617-7061
  - 1617-7061
publication_status: published
publisher: Wiley
status: public
title: A finite strain gradient theory for viscoplasticity by means of micromorphic
  regularization
type: journal_article
user_id: '57708'
volume: 22
year: '2023'
...