• Aluminum foam-filled extrusions subjected to oblique loading: experimental and numerical study 

      Reyes, Aase Gavina Roberg; Hopperstad, Odd Sture; Langseth, Magnus (Journal article; Peer reviewed, 2004)
      The behavior of empty and foam-filled square thin-walled aluminum columns in alloy AA6060 subjected to quasi-static oblique loading was examined. Previous studies have shown that by introducing a load angle, the energy ...
    • Assessment of yield and fracture criteria using shear and bending tests 

      Reyes, Aase Gavina Roberg; Eriksson, Magnus; Lademo, Odd-Geir; Hopperstad, Odd Sture; Langseth, Magnus (Journal article; Peer reviewed, 2009)
      This article deals with the calibration of a fracture criterion that has been implemented in a material model in LS-DYNA. The failure process in thin-walled metallic materials is complex and often due to interaction between ...
    • Constitutive modeling of aluminum foam including fracture and statistical variation of density 

      Reyes, Aase Gavina Roberg; Hopperstad, Odd Sture; Berstad, Torodd; Hanssen, Arve Grønsund; Langseth, Magnus (Journal article; Peer reviewed, 2003)
      An existing constitutive model applicable for aluminum foam was evaluated. The model was implemented in LS-DYNA, and several test cases were analyzed and compared to experimental data. The numerical analyses consisted of ...
    • Crash behavior of obliquely loaded aluminum extrusions 

      Reyes, Aase Gavina Roberg; Langseth, Magnus; Hopperstad, Odd Sture (Chapter, 2002)
      The energy absorbing capability of obliquely loaded aluminum extrusions was studied through quasi-static experiments. Square aluminum columns in alloy AA6060 were clamped at one end and oblique load conditions were realized ...
    • Crashworthiness of aluminum extrusions subjected to oblique loading: experiments and numerical analyses 

      Reyes, Aase Gavina Roberg; Langseth, Magnus; Hopperstad, Odd Sture (Journal article; Peer reviewed, 2002)
      Oblique loading was studied through quasi-static experiments and numerical simulations. The behavior of square aluminum columns in alloy AA6060 subjected to quasi-static oblique loading was investigated experimentally for ...
    • Design and finite element simulations of aluminium foam-filled thin-walled tubes 

      Hanssen, Arve Grønsund; Reyes, Aase Gavina Roberg; Hopperstad, Odd Sture; Langseth, Magnus (Journal article; Peer reviewed, 2005)
      This paper presents experiences gained at SIMLab in modelling and design of aluminium-foam-filled tubes for structural applications. The main challenges for robust finite element simulations using explicit codes are outlined ...
    • Determination of Ductile Fracture Parameters of a Dual-Phase Steel by Optical Measurements 

      Gruben, Gaute; Vysochinskiy, Dmitry; Coudert, Térence; Reyes, Aase Gavina Roberg; Lademo, Odd-Geir (Journal article; Peer reviewed, 2013)
      Marciniak–Kuczynski and Nakajima tests of the dual-phase steel Docol 600DL (www.ssab.com/) have been carried out for a range of stress-states spanning from uniaxial tension to equi-biaxial tension. The deformation histories ...
    • Determination of forming limit strains using Marciniak-Kuczynski tests and automated digital image correlation procedures 

      Vysochinskiy, Dmitry; Coudert, Térence; Reyes, Aase Gavina Roberg; Lademo, Odd-Geir (Journal article; Peer reviewed, 2012)
      Forming limit strains are used to construct a forming limit diagram (FLD), which is a diagram in the principal strain space, traditionally used for designing forming operations of sheet metals. A line indicating the boundary ...
    • Empty and foam-filled circular aluminium tubes subjected to axial and oblique quasi-static loading 

      Børvik, Tore; Hopperstad, Odd Sture; Reyes, Aase Gavina Roberg; Langseth, Magnus; Solomos, G.; Dyngeland, Torbjørn (Journal article; Peer reviewed, 2003)
      Tests on tubular columns made of the aluminium alloy 6060-T4 under axial and oblique, quasi-static loading have been performed. The columns were fixed at one extremity, while a concentrated force was applied at the other ...
    • Energy absorption and damage prevention in a submerged floating tunnel during internal blast loading 

      Tømte, Anders (Master thesis, 2015)
      Experiments on sandwich structures with an aluminum foam core and aluminum sheet plates are done in the shock tube facility at SIMLab. Aluminum foam is a lightweight material with many applications in a wide range of fields. ...
    • Experimental detection of forming limit strains on samples with multiple local necks 

      Vysochinskiy, Dmitry; Coudert, Térence; Hopperstad, Odd Sture; Lademo, Odd-Geir; Reyes, Aase Gavina Roberg (Journal article; Peer reviewed, 2016)
      Sheet metal formability is traditionally described by the forming limit curve (FLC). Experimental FLCs are obtained by performing formability tests and determining failure strains. The strains are usually measured either ...
    • Experimental detection of the onset of local necking in an aluminium sheet 

      Vysochinskiy, Dmitry; Coudert, Térence; Hopperstad, Odd Sture; Lademo, Odd-Geir; Reyes, Aase Gavina Roberg (Journal article; Peer reviewed, 2014)
      Forming limit diagrams (FLDs) are widely used to assess metal sheet formability. Experimental FLDs are obtained by performing formability tests and determining failure strains. The standard method for detection of forming ...
    • Experimental detection of the onset of local necking in an aluminium sheet 

      Vysochinskiy, Dmitry; Coudert, Térence; Hopperstad, Odd Sture; Lademo, Odd-Geir; Reyes, Aase Gavina Roberg (Journal article; Peer reviewed, 2014)
      Forming limit diagrams (FLDs) are widely used to assess metal sheet formability. Experimental FLDs are obtained by performing formability tests and determining failure strains. The standard method for detection of forming ...
    • Experimental study on the formability of AA6016 sheets pre-strained by rolling 

      Vysochinskiy, Dmitry; Coudert, Térence; Hopperstad, Odd Sture; Lademo, Odd-Geir; Reyes, Aase Gavina Roberg (Journal article; Peer reviewed, 2017)
      The effects of prestrain by rolling on the formability of AA6016 sheets in the biaxial stretching region are studied in this paper. An experimental program including formability experiments has been carried out for as-received ...
    • Foam Materials used for Energy Absorption and Damage Prevention during Blast Loading 

      Sigurdsson, Bjarki (Master thesis, 2016)
      Following several high profile bomb attacks in the western hemisphere in recent years, e.g. Brussels 2016 and Norwegian government quarter 2011, the protection of structures against blast loading has received a lot of ...
    • Forming limit diagrams with an FE-based approach for sheets under non-proportional loading 

      Reyes, Aase Gavina Roberg; Hopperstad, Odd Sture; Berstad, Torodd; Lademo, Odd-Geir (Chapter, 2009)
      In this study, LS-DYNA was used to predict the experimental forming limit diagrams (FLDs) for prestrained sheets in aluminum alloy Al2008-T4 found by Graf and Hosford [1]. The original data of Graf and Hosford [1] includes ...
    • Impact behaviour of foam-based protective structures 

      Berdal, Sindre; Bjørgo, Lars Einar Uhlen (Master thesis, 2017)
      Foams are three dimensional cellular materials, with cell walls made up of a solid or liquid material and cells containing a gas or liquid. The solid material can be anything from a metal to a ceramic. Metallic and polymeric ...
    • Material characterization and modeling of textured aluminum alloys used in a bumper system 

      Reyes, Aase Gavina Roberg; Hopperstad, Odd Sture; Lademo, Odd-Geir; Langseth, Magnus (Chapter, 2005)
      In the present paper, two materials AA7108 and AA6060, which can be parts of a typical bumper system in aluminum, have been characterized. Material properties were identified for a material model that was recently implemented ...
    • Mechanical response of low density expanded polypropylene foams in compression and tension at different loading rates and temperatures 

      Morton, Daniel Thor; Reyes, Aase Gavina Roberg; Clausen, Arild Holm; Hopperstad, Odd Sture (Journal article; Peer reviewed, 2020)
      Polymer foams are often used for impact mitigation and protection due to low weight and excellent energy absorbing capability. Depending on the application, different loading rates and environmental conditions can be ...
    • Modeling of material failure in foam-based components 

      Reyes, Aase Gavina Roberg; Hopperstad, Odd Sture; Hanssen, Arve Grønsund; Langseth, Magnus (Journal article; Peer reviewed, 2004)
      The modeling of material failure in foam-filled beams was explored through numerical analyses with LS-DYNA. The study was based on previous physical tests on bending of square aluminum extrusions filled with aluminum foam. ...