Ändra sökning
Avgränsa sökresultatet
1 - 8 av 8
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Träffar per sida
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
Markera
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Blanco, N.
    et al.
    EPS-University of Girona.
    Gamstedt, E.K.
    Royal Institute of Technology (KTH).
    Asp, Leif
    RISE, Swerea, Swerea SICOMP AB.
    Costa, J.
    EPS-University of Girona.
    Mixed-mode delamination growth in carbon-fibre composite laminates under cyclic loading2004Ingår i: International Journal of Solids and Structures, ISSN 0020-7683, E-ISSN 1879-2146, Vol. 41, nr 15, s. 4219-4235Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Delamination growth under fatigue loads in real composite components generally develops in a non-constant propagation mode. The aim of the investigation described in this article was to develop a model capable of predicting the fatigue delamination growth in a general case, under varying mode mix conditions. The crack growth development in essentially unidirectional laminates of carbon-fibre reinforced epoxy was analysed in terms of the Paris law for different constant propagation modes: mode I (double-cantilever beam test), mode II (end-notched flexure test) and different mixed-modes I/II (mixed-mode bending test). The dependence of the Paris law parameters on mode mix is compared with the existing models in the literature. It is shown that these models do not reproduce the non-monotonic dependence on mode mix which has been observed in experimental data. Therefore, an improved phenomenological model is introduced and compared with the experimental data obtained by other researchers. To check the ability of the model to predict variable mixed-mode fatigue delamination, the mixed-mode end-loaded split test was employed and the experimental results were compared to the predictions of the model. The underlying mechanisms responsible for the dependency of the crack propagation rates on the degree of mode mix are also discussed on the basis of fractographic analysis. © 2004 Elsevier Ltd. All rights reserved.

  • 2.
    Bouckaert, Igor
    et al.
    UCLouvain, Belgium.
    Godio, Michele
    RISE Research Institutes of Sweden, Material och produktion, Kemi och Tillämpad mekanik.
    Pacheco de Almeida, João
    UCLouvain, Belgium.
    A Hybrid Discrete-Finite Element method for continuous and discontinuous beam-like members including nonlinear geometric and material effects2024Ingår i: International Journal of Solids and Structures, ISSN 0020-7683, E-ISSN 1879-2146, Vol. 294, artikel-id 112770Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    This paper introduces a novel formulation, called Hybrid Discrete-Finite Element (HybriDFEM) method, for modeling one-directional continuous and discontinuous planar beam-like members, including nonlinear geometric and material effects. In this method, the structure is modeled as a series of distinct rigid blocks, connected to each other through contact pairs distributed along the interfaces. Each of those contact pairs are composed of two nonlinear multidirectional springs in series, which can represent either the deformation of the blocks themselves, or the deformation of their interface. Unlike the Applied Element Method, in which contact pairs are composed of one single spring, the current approach allows capturing phenomena such as sectional deformations or relative deformations between two blocks composed of different materials. This method shares similarities with the Discrete Element Methods in its ability to model contact interfaces between rigid or deformable units, but does not require a numerical time-domain integration scheme. More importantly, its formulation resembles that of the classical Finite Elements Method, allowing one to easily couple the latter with HybriDFEM. Following the presentation of its formulation, the method is benchmarked against analytical solutions selected from the literature, ranging from the linear-elastic response of a cantilever beam to the buckling and rocking response of continuous flexible columns, and rigid block stackings. One final example showcases the coupling of a HybriDFEM element with a linear beam finite element.

    Ladda ner fulltext (pdf)
    fulltext
  • 3.
    Josefsson, Gabriella
    et al.
    Uppsala University, Sweden.
    Berthold, Fredrik
    RISE., Innventia.
    Gamstedt, Erik Kristofer
    Uppsala University, Sweden.
    Stiffness contribution of cellulose nanofibrils to composite materials2014Ingår i: International Journal of Solids and Structures, ISSN 0020-7683, E-ISSN 1879-2146, Vol. 51, nr 5, s. 945-953Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nanocomposites, reinforced by different types of cellulose fibrils, have gained increased interest the last years due to the promising mechanical properties. There is a lack of knowledge about the mechanical properties of the cellulose fibrils, and their contribution to the often claimed potential of the impressive mechanical performance of the nanocomposites. This paper investigates the contribution from different types of cellulose nanofibril to the overall elastic properties of composites. A multiscale model is proposed, that allows back-calculation of the elastic properties of the fibril from the macroscopic elastic properties of the composites. The different types of fibrils used were nanofibrillated cellulose from wood, bacterial cellulose nano-whiskers and microcrystalline cellulose. Based on the overall properties of the composite with an unaged polylactide matrix, the effective longitudinal Young's modulus of the fibrils was estimated to 65 GPa for the nanofibrillated cellulose, 61 GPa for the nano whiskers and only 38 GPa for the microcrystalline cellulose. The ranking and absolute values are in accordance with other studies on nanoscale morphology and stiffness estimates. Electron microscopy revealed that in the melt-processed cellulose nanofibril reinforced thermoplastics, the fibrils tended to agglomerate and form micrometer scale platelets, effectively forming a microcomposite and not a nanocomposite. This dispersion effect has to be addressed when developing models describing the structure-property relations for cellulose nanofibril composites.

  • 4.
    Larsson, R.
    et al.
    Chalmers University of Technology, Sweden.
    Singh, Vivekendra
    RISE Research Institutes of Sweden, Material och produktion, Polymera material och kompositer. Chalmers University of Technology, Sweden.
    Olsson, Robin
    RISE Research Institutes of Sweden, Material och produktion, Polymera material och kompositer. Chalmers University of Technology, Sweden.
    Marklund, Erik
    RISE Research Institutes of Sweden, Material och produktion, Polymera material och kompositer.
    A micromechanically based model for dynamic damage evolution in unidirectional composites2022Ingår i: International Journal of Solids and Structures, ISSN 0020-7683, E-ISSN 1879-2146, Vol. 238, artikel-id 111368Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This article addresses the micromechanically motivated, quasistatic to dynamic, failure response of fibre reinforced unidirectional composites at finite deformation. The model draws from computational homogenization, with a subscale represented by matrix and fibre constituents. Undamaged matrix response assumes isotropic viscoelasticity–viscoplasticity, whereas the fibre is transversely isotropic hyperelastic. Major novelties involve damage degradation of the matrix response, due to shear in compression based on a rate dependent damage evolution model, and the large deformation homogenization approach. The homogenized quasi-brittle damage induced failure is described by elastically stored isochoric energy and plastic work of the undamaged polymer, driving the evolution of damage. The developed model is implemented in ABAQUS/Explicit. Finite element validation is carried out for a set of off-axis experimental compression tests in the literature. Considering the unidirectional carbon–epoxy (IM7/8552) composite at different strain rates, it appears that the homogenized damage degraded response can represent the expected ductile failure of the composite at compressive loading with different off-axes. Favourable comparisons are made for the strain and fibre rotation distribution involving localized shear and fibre kinking. © 2021 The Authors

  • 5. Nygårds, Mikael
    et al.
    Just, M.
    Tryding, J.
    Experimental and numerical studies of creasing of paperboard2009Ingår i: International Journal of Solids and Structures, ISSN 0020-7683, E-ISSN 1879-2146, Vol. 46, nr 11-12, s. 2493-2505Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A laboratory creasing device to capture the most important properties of a commercial rotary creasing tool was designed. Finite element analysis of the creasing of a multiply paperboard in the laboratory crease device was presented. The multiply paperboard was modeled as a multilayered structure with cohesive softening interface model connecting the paperboard plies. The paperboard plies were modeled by an anisotropic elastic-plastic material model. The purpose of the analysis of the laboratory creasing device was to present material models that represent paperboard, and to investigate how well the analysis captured the multiply paperboard behavior during laboratory creasing. And to increase the understanding of what multiply paperboard properties that influence the laboratory crease operation. The result of the simulations showed very good correlations with the experimental obtained results. The results indicated that the paperboard properties that have the most influence is the out-of-plane shear, out-of-plane compression and the friction between the laboratory creasing device and the paperboard. © 2009 Elsevier Ltd. All rights reserved.

  • 6.
    Olsson, Robin
    RISE - Research Institutes of Sweden, Material och produktion, SICOMP.
    Analytical model for delamination growth during small mass impact on plates2010Ingår i: International Journal of Solids and Structures, ISSN 0020-7683, E-ISSN 1879-2146, Vol. 47, nr 21, s. 2884-2892Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An analytical model is presented for delamination initiation and growth and the resulting response during small mass impact on orthotropic laminated composite plates, which typically is caused by runway debris and other small objects. The solution is obtained by a fast stepwise numerical solution of a single integral equation. Delamination size, load and deflection history are predicted by extension of an earlier elastic impact model by the author. Good agreement is demonstrated in comparisons with finite element simulations and experiments. © 2010 Elsevier Ltd. All rights reserved.

  • 7.
    Pham, Quoc Tuan
    et al.
    Blekinge Institute of Technology, Sweden.
    Islam, Md Shafiqul
    Blekinge Institute of Technology, Sweden.
    Sigvant, Mats
    Blekinge Institute of Technology, Sweden; Volvo Cars, Sweden.
    Pérez Caro, Lluís
    RISE Research Institutes of Sweden, Material och produktion, Tillverkningsprocesser.
    Lee, Myoung-Gyu
    Seoul National University, South Korea.
    Kim, Young-Suk
    Kyungpook National University, South Korea.
    Improvement of modified maximum force criterion for forming limit diagram prediction of sheet metal2023Ingår i: International Journal of Solids and Structures, ISSN 0020-7683, E-ISSN 1879-2146, Vol. 273, artikel-id 112264Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study presents a new criterion (MMFC2) for predicting the forming limit curve (FLC) of sheet metal. The strain path evolution of a critical element examined in a uniaxial tensile test is elaborated by incorporating the results of experimental measurement, finite element simulation, and theoretical prediction via the Modified Maximum Force Criterion (MMFC). A scaling factor is introduced to mimic the theoretical evaluation with the simulated one. It is believed that the rotation of the principal axes of the theoretically considering material point, which is initially co-axial with the external load coordinate, implicates the macro track of the strain path change. Furthermore, an optimal event of the second derivative of the axial rotations is proposed to indicate the strain localization and formulate the FLC. The performance of the proposed criterion is compared with that of the original MMFC in predicting the FLC of three automotive sheet metals, of which all related data were published in the Benchmark of Numisheet 2014 conference. The use of three different hardening laws and three yield functions is examined in the analogy. The comparison reveals that the results of MMFC2 are more sensitive to the employed constitutive model than that of MMFC. Furthermore, the proposed MMFC2 presents concordant results with the experimental data. Nakajima tests are conducted for CR4 mild steel sheets to validate the capacity of the proposed criterion. Well agreement between the experimentally measured data and theoretical prediction based on the Yld2k yield function verifies its usefulness in practice. © 2023 The Author(s)

  • 8.
    Zang, W.L.
    et al.
    Royal Institute of Technology.
    Gudmundson, Peter
    RISE, Swerea, Swerea SICOMP AB.
    Kinked cracks in an anisotropic plane modeled by an integral equation method1991Ingår i: International Journal of Solids and Structures, ISSN 0020-7683, E-ISSN 1879-2146, Vol. 27, nr 14, s. 1855-1865Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A boundary integral method for cracks in an anisotropic material is presented. The method is based on the integral equation for the resultant forces along the cracks. The integral kernels contain only a weak logarithmic singularity, which simplifies the numerical implementation. Crack closure is also taken into account in the numerical formulation. Numerical tests are presented to illustrate the efficiency and the reliability of the proposed method. © 1991.

1 - 8 av 8
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf