• Bending of X65 Offshore Steel Pipes 

      Lofthaug, Kristoffer; Digerud, Erik (Master thesis, 2014)
      This thesis is part of an ongoing research program between SIMLab and Statoil about impact loads on X65 offshore pipelines and it is a continuation of previous work.Offshore pipelines are frequently impacted by accidental ...
    • Brannen var påsatt 

      Olsen, Ørjan Berg; Kristoffersen, Martin (Bachelor thesis, 2014-07-17)
      Denne oppgaven har analysert i hvilken grad veiledning til teknisk forskrift, ivaretar sikkerhet mot påsatte branner. Oppbyggingen er basert på NS 5814:2008 Krav til risikovurderinger. En vesentlig del er også kartlegging ...
    • Deformasjon av trykksatte rørledninger 

      Jakobsen, Espen (Master thesis, 2013)
      Offshore pipelines may be subjected to impact by anchor and trawl gear. An anchor impact will drag the pipeline out of its position, before it is released and the pipe straightens, due to the rebound and large axialforces. ...
    • Denting of coated and uncoated offshore steel pipes 

      Holm, Nicolay Line; Røshol, Eivind Torgunrud (Master thesis, 2015)
      In the present thesis, numerical and experimental investigations of coated offshore pipelines were conducted. The objective was to investigate how the polypropylene coating affected the global response of the pipes. The ...
    • Digital effektkontroller basert på el-gitarens vibarm 

      Kristoffersen, Martin (Master thesis, 2017)
      Denne masteroppgaven gikk ut på å lage en digital effektkontroller basert på el-gitarens vibarm, med formål om å berike gitaristens lydpalett med sømløs styring av lydeffekter som ikke kompliserer spillemåten, men snarere ...
    • Dynamic versus quasi-static loading of X65 offshore steel pipes 

      Kristoffersen, Martin; Børvik, Tore; Langseth, Magnus; Hopperstad, Odd Sture (Journal article; Peer reviewed, 2016)
      Anchors or trawl gear occasionally impact offshore pipelines, resulting in large local and global deformations. Impact velocities are typically less than 5 m/s, but local strain rates may be very high. In this study strain ...
    • 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. ...
    • Fragmentation of metallic materials during impact 

      Kristoffersen, Martin; Hyland, Even (Master thesis, 2010)
      Studies on shear-plug formation and on double-layered steel plates impacted by blunt-nosed hardened steel projectiles showed that at certain velocities against certain targetplates the projectiles shattered upon impact. ...
    • Impact against empty and water-filled X65 steel pipes - Experiments and simulations 

      Kristoffersen, Martin; Casadei, Folco; Børvik, Tore; Langseth, Magnus; Hopperstad, Odd Sture (Journal article; Peer reviewed, 2014)
      Offshore pipelines are frequently subjected to accidental impact loads, e.g. from anchors or trawl gear. A lot of parameters – including the pipe geometry, material properties, pipeline content, impact velocity, etc. – ...
    • Impact Against Offshore Pipelines 

      Mogstad, Ivar; Asheim, Tom Inge (Master thesis, 2013)
      Impact against offshore pipelines is investigated in this thesis. Introductory low velocity experiments on pipeline specimens using the stretch bending rig at the Department of Structural Engineering, NTNU, were carried ...
    • Impact against X65 offshore pipelines 

      Kristoffersen, Martin (Doctoral thesis at NTNU;2014:362, Doctoral thesis, 2014)
      This thesis presents both experimental and numerical investigations into some of the plethora of parameters influencing pipeline impact behaviour and the potential fracture arising thereof. The seamless pipes studied are ...
    • Impact against X65 steel pipes - An experimental investigation 

      Kristoffersen, Martin; Børvik, Tore; Westermann, Ida; Langseth, Magnus; Hopperstad, Odd Sture (Journal article; Peer reviewed, 2013)
      Offshore pipelines subjected to accidental loads, such as impacts from trawl gear or anchors, may experience large global displacements from its initial position and large local strains. The axial forces set up during ...
    • NUMERICAL SIMULATIONS OF SUBMERGED AND PRESSURISED X65 STEEL PIPES 

      Kristoffersen, Martin; Casadei, Folco; Børvik, Tore; Langseth, Magnus; Solomos, George; Hopperstad, Odd Sture (Chapter; Conference object, 2013)
      While in service, pipelines may from time to time be exposed to impact loads from anchors or trawl gear. A lot of parameters influence the behaviour of the pipeline during impact, e.g. the diameter and thickness of the ...
    • Transverse Deformation of Pressurised Pipes With Different Axial Loads 

      Kristoffersen, Martin; Børvik, Tore; Langseth, Magnus; Ilstad, Håvar; Levold, Erik (Chapter; Peer reviewed, 2017)
      Pipelines residing on the seabed are exposed to various hazards, one of them being denting, hooking and release of the pipeline by e.g. anchors or trawl gear. As a pipeline is displaced transversely in a hooking event, an ...
    • Using unit cell simulations to investigate fracture due to compression-tension loading 

      Kristoffersen, Martin; Børvik, Tore; Hopperstad, Odd Sture (Journal article; Peer reviewed, 2016)
      Experiments regarding impact against X65 steel pipes show that fracture typically arises in areas subjected to large compressive strains before tension. Fracture surfaces from these areas are brittle in character despite ...