Sökning: "welded details"

Visar resultat 1 - 5 av 7 avhandlingar innehållade orden welded details.

1. 1. Fatigue evaluation of welded details – using the finite element method

   Författare :Mustafa Aygül; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; the finite element method; welded details; effective notch stress method; Hot-spot stress method; fracture mechanics;

   Sammanfattning : The fatigue evaluation of welded details is generally based on the notion of nominal stress, using the classified S-N curves with corresponding fatigue classes for typical details. An approach of this kind should be used with extra caution to ensure that the load effects for components are accurately captured, because an ever-increasing number of welded details are resulting in a limited number of possible treatable design cases. LÄS MER

3. 2. Multi-axial fatigue of welded details

   Författare :Mathias Bokesjö; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : Welds and welded joints are nowadays very common in steel structures. Since thewelded parts also are susceptible to fatigue, they can have a major influence on thetotal life of the structure. LÄS MER

4. 3. Fatigue Analysis of Welded Structures Using the Finite Element Method

   Författare :Mustafa Aygül; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hot spot stress; effective notch stress; the finite element method; orthotropic bridge deck; welded details;

   Sammanfattning : Fatigue design and analysis of steel and composite bridges is generally based on the notion of the nominal stress using the classified S-N curves with corresponding fatigue classes for typical details. Such an approach can yield unrealistic the estimation of the load effects for structure components because of an ever increasing number of structural details and loading situations resulting in a limited number of possible treatable design cases. LÄS MER

5. 4. Fatigue life extension in existing steel bridges. High-Frequency Mechanical Impact treatment and Tungsten Inert Gas remelting in life extension and fatigue crack repair of welded steel structures

   Författare :Hassan al-Karawi; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HFMI; TIG-dressing; Life extension; Post weld treatment; Gain factor; Linear elastic fracture mechanics; Crack retrofiting; Peening; fatigue crack; Crack detection; Microhardness; Concentration factor; LEFM; TIG-remelting; Strain gauge;

   Sammanfattning : This thesis investigates the performance of improved welds with two post-weld treatment methods for application on existing structures. High-Frequency Mechanical Impact (HFMI) treatment and Tungsten Inert Gas (TIG) remelting were used for fatigue life extension of welded structures. LÄS MER

7. 5. A study of the fatigue behaviour of laser and hybrid laser welds

   Författare :Md. Minhaj Alam; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Manufacturing Systems Engineering; Produktionsutveckling;

   Sammanfattning : This licentiate thesis focuses on the fatigue cracking behaviour of laser and hybrid laser-MAG welded structures. Beside the welding process and the resulting weld, several topics related to fatigue of welded structures are treated such as; macro and micro surface geometry, weld defects and their influence on fatigue performance of welded structures, fatigue analysis by the nominal and effective notch stress method, fatigue life prediction using LEFM (Linear Elastic Fracture Mechanics), fatigue testing, metallurgical analysis, elastic and elastic-plastic finite element analysis. LÄS MER