Sökning: "crack path"

Visar resultat 1 - 5 av 46 avhandlingar innehållade orden crack path.

1. 1. Crack growth paths in rolling contact fatigue — Numerical predictions

   Författare :Mohammad Salahi Nezhad; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vector crack tip displacement; Crack face friction; Crack growth direction; Crack propagation; Rolling contact fatigue;

   Sammanfattning : Rolling contact fatigue (RCF) cracks in railway wheels and rails are costly and complex to deal with. Despite the extensive research efforts that have been put into understanding the mechanisms and developing appropriate predictive models for RCF crack growth, there are still a lot of open questions. LÄS MER

3. 2. Behaviour of fracture process zones in concrete influenced by simultaneously applied normal and shear displacements

   Författare :Manouchehr Hassanzadeh; Avdelningen för Byggnadsmaterial; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; softening; mixed mode; fictitious crack model; concrete; deformationer; betong; brottmekanik; hållfasthet; brotthållfasthet; spänningar; skjuvspänningar; sprickor; beräkningsmodeller; brottenergi; teori; laboratorieförsök; interlock; crack path; diagonal crack; microcracking; instability; fracture energy; fracture mechanics; shear; tension; process zone;

   Sammanfattning : The thesis deals with the determination of the post peak behaviour of concrete in pure tension, and combined tension (compression) and shear. A test arrangement has been developed in order to determine the post peak behaviour of concrete expressed as stress - displacement curves. LÄS MER

4. 3. Comprehensive numerical analysis of stress state in adhesive layer of joint including thermal residual stress and material non-linearity

   Författare :Nawres Jabar Al-Ramahi; Roberts Joffe; Janis Varna; Lars Mikkelsen; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Single-lap adhesive joint; Double-lap adhesive joint; Unbalanced bi-material DCB; Residual thermal stresses; Finite element method; Crack path; Crack closure; Polymeric Composite Materials; Polymera kompositmaterial;

   Sammanfattning : The main objective of this work is to improve understanding of the stress state in the adhesive layer of bonded joints and identify key parameters which govern performance of adhesive joints. This information is crucial for the prediction of the failure initiation and propagation with the further estimation of the durability and strength of adhesively bonded structures. LÄS MER

5. 4. Modelling of surface initiated rolling contact fatigue crack growth using the asperity point load mechanism

   Författare :Dave Hannes; Bo Alfredsson; Anders Ekberg; KTH; []
   Nyckelord :rolling contact fatigue; spalling; asperity; fatigue crack path; fatigue crack growth; mode I; plane mixed-mode; TECHNOLOGY; TEKNIKVETENSKAP;

   Sammanfattning : .... LÄS MER

7. 5. On the Fracture of Thin Laminates

   Författare :Sharon Kao-Walter; Blekinge Institute of Technology; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Laminate; interface; crack; adhesion; crack tip driving force;

   Sammanfattning : This thesis concerns mechanical and fracture properties of a thin aluminium foil and polymer laminate that is widely used as packaging material. The possibility of controlling the path of the growing crack propagation by adjustment of the adhesion level and the property of the polymer layer is investigated. LÄS MER