Search for dissertations about: "Probability of fatigue failure"

Showing result 1 - 5 of 13 swedish dissertations containing the words Probability of fatigue failure.

2. 1. Fatigue of existing steel bridges : Reliability and risk analyses for decision-making

   Author : Ruoqi Wang; John Leander; Raid Karoumi; Boulent Imam; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fatigue; steel bridges; decision-making; reliability analysis; risk analysis; spatial correlation; system modelling; inspection and maintenance; Utmattning; stålbroar; beslutsfattande; tillförlitlighet; riskanalys; rumslig korrelation; systemmodellering; inspektion och underhåll; Bro- och stålbyggnad; Structural Engineering and Bridges;

   Abstract : Fatigue is one of the primary reasons that limit the service life of steel bridges. Many bridges in Sweden and other countries have progressively approached their anticipated service lives. Since funding and resources are limited, simultaneously replacement or maintenance of bridges is impractical. READ MORE

4. 2. A Framework for optimised welding of fatigue loaded structures : Applied to gas metal arc welding of fillet welds

   Author : Erik Åstrand; Gunnar Bolmsjö; Fredrik Sikström; Heikki Remes; Högskolan Väst; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; GMAW; Fatigue; Welding procedures; Fillet welds; Weld quality; Production Technology; Produktionsteknik; Manufacturing and materials engineering; Produktions- och materialteknik;

   Abstract : Welding is a key process for heavy steel structures, but it is also a weak link in the structure since fatigue fractures in welds are a common cause of failure. This thesis proposes several changes in order to improve the fatigue properties in acost effective way, enabling reduced weight and reduced cost of welded structures. READ MORE

5. 3. Wheels, Rails and Insulated Joints - Damage and Failure Probability at High Speed and Axle Load

   Author : Johan Sandström; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rail breaks; probability; railway mechanics; contact mechanics; insulated joints; defects; fatigue;

   Abstract : The thesis deals with some fatigue related problems in railway mechanics related to increased axle loads and speeds. The focus is on defects and discontinuities in the wheel--rail system that affect the risk of fatigue and fracture of railway components such as wheels, rails and insulated joints. READ MORE

6. 4. Influence of microstructure on fatigue and ductility properties of tool steels

   Author : Mats Randelius; Rolf Sandström; Jens Bergström; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tool steels; fatigue; ductility; carbides; carbide cluster; inclusion; size distribution; modelling; FEM; Metallurgical process engineering; Metallurgisk processteknik;

   Abstract : Fatigue and ductility properties in various tool steels, produced by powder metallurgy, spray forming or conventionally ingot casting, have been analysed experimentally and successfully compared to developed models. The models are able to predict the fatigue limit and cause for fatigue fracture, and strain- and stress-development until fracture during the ductile fracture process respectively. READ MORE

7. 5. Topology Optimization of Fatigue-Constrained Structures

   Author : Henrik Svärd; Krister Svanberg; Pierre Duysinx; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; topology optimization; fatigue constraints; stress constraints; density filters; restriction methods; weakest link theory; critical plane criteria; Mathematics; Matematik;

   Abstract : Fatigue, or failure of material due to repeated cyclic loading, is one of the most common causes of mechanical failures. The risk of fatigue in a load carrying component is often lowered by adding material, thereby reducing stresses. READ MORE