Search for dissertations about: "internal stresses"

Showing result 1 - 5 of 71 swedish dissertations containing the words internal stresses.

2. 1. Internal Erosion Phenomena in Embankment Dams : Throughflow and internal erosion mechanisms

   Author : Farzad Ferdos; Anders Wörman; Bijan Dargahi; Fredrik Johansson; Willi Hager; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Internal erosion modelling in porous material; Constitutive law of erosion for closure of continuum-mechanics-based balance equations for numerical modelling; High Reynolds-number turbulent flow; Flow laws; Coarse rockfill material throughflow; Computational Fluid Dynamics.; Civil and Architectural Engineering; Byggvetenskap;

   Abstract :  In this study, two major internal erosion initiation processes, suffusion and concentrated leak mechanisms, which lead to both defect formation in a dam’s body and its foundation and high throughflow in dams subjected to internal erosion were studied. This understanding has the potential to facilitate numerical modelling and expedite dam safety assessment studies. READ MORE

4. 2. Moisture Induced Stresses in Timber Structures

   Author : Johan Jönsson; Avdelningen för Konstruktionsteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Teknik; load carrying capacity; Technological sciences; reinforcement; short-term strength perpendicular to grain; internal stresses; glulam; contact free measuring technique moisture gradients;

   Abstract : Wood is a hygroscopic material; always striving to reach equilibrium with the surrounding air, and consequently the moisture content is different in different climate conditions. The strength of wood is directly dependent on the moisture content, lower moisture content leads to increasing strength. READ MORE

5. 3. Internal Stresses in Wood Caused by Climate Variations

   Author : Staffan Svensson; Avdelningen för Konstruktionsteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Construction technology; climate variations.; sawn timber; kiln drying; mechano-sorption; hygro-mechanical; Wood; material testing; Anläggningsteknik;

   Abstract : This thesis is the result of a series of investigations on the hygro-mechanical behaviour of clear wood in the radial and tangential directions. Approximately half of the effort put into the investigations was concentrated on laboratory tests while the remaining effort was concentrated on modelling the observations made in the tests. READ MORE

6. 4. Laser cladded steel - microstructures and mechanical properties of relevance for railway applications

   Author : Simon Niederhauser; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fe-Cr alloy; Carbon Steel; Microstructure; Internal Stresses; HAZ; Laser Cladding; Co-Cr alloy; Cracking Behaviour; Mechanical Properties; Low Cycle Fatigue;

   Abstract : Owing to increased requirements like increased axle load for railway wheels and rails, new material have to be employed. However, these requirements are mostly surface related, which makes it appropriate to change only the surface layer while keeping the bulk unchanged. READ MORE

7. 5. Hydrolytic degradation of dental composites and effects of silane-treatment and filler fraction on compressive strength and thermal expansion of composites

   Author : Karl-Johan M. Söderholm; Umeå universitet; []
   Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Internal frictional theory; filler-matrix debonding; stress-corrosion; stressinfluenced diffusion; m icro-crack form ation; crazing; opacity; wear; osmotic pressure; hoop stresses;

   Abstract : Some researchers have suggested that the weakest link of dental composites is the filler-matrix bond. However, due to incompleteness of information dealing with this bond and its stability in a humid environment, it was considered desirable to investigate the effect of water on this region, as well as the influence of filler bonding and filler fraction on compressive strength and thermal expansionExperimental composites containing different filler fractions of either silane-treated or untreated fillers were made. READ MORE