Search for dissertations about: "Dynamic fracture"

Showing result 1 - 5 of 76 swedish dissertations containing the words Dynamic fracture.

2. 1. Heterogeneous Bonded Particle Modelling of Rock Fracture

   Author : Albin Wessling; Jörgen Kajberg; Simon Larsson; Pär Jonsén; Timo Saksala; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Rock; DEM; BPM; fracture; drilling; dynamic; Solid Mechanics; Hållfasthetslära;

   Abstract : The dynamic fracture process of rock materials is of importance for several industries, such as the rock drilling process in geothermal and mining applications. Gaining knowledge and understanding of dynamic rock fracture through numerical simulations can enhance the rock drilling process, for example by optimising the drill bit geometry and drilling parameters. READ MORE

4. 2. Experiments and modelling of fracture initiation at impact

   Author : Ola Wall; Hållfasthetslära; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vibration and acoustic engineering; vacuum technology; hydraulics; Viscoplasticity; Mechanical engineering; Ductile; Brittle; Dynamic; Fracture; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik; Material technology; Materiallära; materialteknik;

   Abstract : The thesis addresses different questions, each necessary in the understanding of dynamic fracture initiation and crack propagation in steel. Emphasis lays on dynamic crack propagation experiments performed in the ductile to brittle transition region and possible conclusions, that can be drawn from them. READ MORE

5. 3. Simulation of dynamic instabilities during high rate deformation of ductile bars and plates

   Author : Kristina Nilsson; Mekanik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; numerical simulation; non-linear; wave propagation; multiple necking; necking; buckling; fracture; Mechanical engineering; Maskinteknik; finite elements; cohesive elements; dynamic; J2-flow theory; J2-deformation theory; viscoplastic; background inertia;

   Abstract : In this thesis, some of the phenomena occurring in plates and cylindrical bars subjected to dynamic loading are investigated. Numerical simulations using a dynamic finite element code are performed for a number of different sized specimens with various initial surface imperfections. Typically imposed loading velocities are in the range 10m/s.. READ MORE

6. 4. Non-Linear Vibration and Dynamic Fracture Mechanics of Bridge Cables

   Author : Armando Leon; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cable Vibrations; Non-Linear Vibration; Dynamic Fracture Mechanics; Cable-Stayed Bridges; Dynamic Stress Intensity Factor;

   Abstract : In the present work, the non-linear vibrations and the corresponding dynamic fracture mechanics of cables of cable-stayed bridges are studied. The cables are among the most critical components in cable-stayed bridges and there are different damage sources such as corrosion, vibration, fatigue and fretting fatigue that can significantly affect them, thereby reducing the cable’s service life and even producing their failure. READ MORE

7. 5. Hip fractures : A biomechanical analysis of fracture strength prediction, prevention, and repair

   Author : Joeri Kok; Avdelningen för Biomedicinsk teknik; []
   Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Finite element; Bone cement; Femur; Fracture; Experimental mechanics; X-ray imaging;

   Abstract : Due to the aging population, hip fracture incidence has been increasing over the past decades. Measurements of bone mineral density with dual energy X-ray absorptiometry are the gold standard for hip fracture risk assessment, where patients with a low bone density have a high risk of fracture. READ MORE