Sökning: "uniaxial stress"

Visar resultat 6 - 10 av 60 avhandlingar innehållade orden uniaxial stress.

1. 6. The effect of stress state in ductile failure

   Författare :Imad Barsoum; Jonas Faleskog; Viggo Tvergaard; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ductile failure; Rupture mechanisms; Stress triaxiality; Lode parameter; Finite element analysis; Experiments; Localization; Micromechanics; Void growth; Void coalescence; Engineering mechanics; Teknisk mekanik;

   Sammanfattning : The industrial application of high strength steels in structural components has increased the demand on understanding the ductile failure behavior of this type of materials. In practical situations the loading experienced on components made out of these materials can be very complex, which may affect the failure behavior. LÄS MER

3. 7. Strength and deformability of fractured rocks

   Författare :Majid Noorian-Bidgoli; Lanru Jing; John A. Hudson; KTH; []
   Nyckelord :Fractured crystalline rocks; Numerical experiments; Discrete element methods DEM ; Discrete fracture network DFN ; Representative elementary volume REV ; Coupled hydro-mechanical processes; Anisotropy; Effective stress; Failure criteria; Stochastic realizations; Land and Water Resources Engineering; Mark- och vattenteknik;

   Sammanfattning : This thesis presents a systematic numerical modeling framework to simulate the stress-deformation and coupled stress-deformation-flow processes by performing uniaxial and biaxial compressive tests on fractured rock models with considering the effects of different loading conditions, different loading directions (anisotropy), and coupled hydro-mechanical processes for evaluating strength and deformability behavior of fractured rocks. By using code UDEC of discrete element method (DEM), a series of numerical experiments were conducted on discrete fracture network models (DFN) at an established representative elementary volume (REV), based on realistic geometrical and mechanical data of fracture systems from field mapping at Sellafield, UK. LÄS MER

4. 8. Experimental characterization and numerical modeling of compression perpendicular to the grain in wood and cross-laminated timber

   Författare :Shaheda T. Akter; Thomas K. Bader; Erik Serrano; Jan Oscarsson; Reinhard Brandner; Linnéuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rolling shear; biaxial testing; stress combination; RT-plane; moisture influence; rolling shear creep; digital image correlation; strain field; CLT connection; rotational stiffness; rullskjuvning; biaxiell undersökning; spänningskombination; RT-plan; fuktpåverkan; krypning vid rullskjuving; digital bildkorrelation; töjningsfält; KLTanslutning; rotationsstyvhet; Byggteknik; Civil engineering;

   Sammanfattning : Compression perpendicular to the grain (CPG) of wood is a typical loading situation in timber structures. It has been an extensively studied research topic for decades, due to the highly ductile behavior of wood under such loading, the large variations in mechanical properties, and the relevance of these properties in structural design. LÄS MER

5. 9. Very high cycle fatigue of automotive steels : Testing and computation at 20 kHz

   Författare :Mohamed Sadek; Jens Bergström; Nils Hallbäck; Ulrich Krupp; Karlstads universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Very high cycle fatigue; ultrasonic fatigue testing; automotive steels; fatigue strength; stress intensity computation; crack growth; Materialteknik; Materials Engineering;

   Sammanfattning : Mechanical fatigue failure occurs in components subjected to cyclic loading. A crack initiates at critical regions in the component and propagates during repeated loading. The expected fatigue life depends on the level, type and frequency of the loading. LÄS MER

7. 10. Effects of Steel Fibres on Cracking in Reinforced Concrete

   Författare :Anette M Jansson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; uniaxial tension test; Keywords: Self-compacting; characteristic crack width; fibre-reinforced; bond; tension stiffening; Digital Image Correlation; pull-out test;

   Sammanfattning : ABSTRACTAlthough it is well known that fibre reinforcement acts as a crack arresting agent, there is still a need for deeper knowledge of the actual cracking behaviour, especially regarding cracks with widths smaller than 0.3mm. LÄS MER