Search for dissertations about: "deterioration mechanisms"

Showing result 1 - 5 of 81 swedish dissertations containing the words deterioration mechanisms.

2. 1. Mechanisms of salt frost scaling on portland cement-bound materials: studies and hypothesis

   Author : Sture Lindmark; Avdelningen för Byggnadsmaterial; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Deterioration; Durability; Freeze-Thaw; Frost; Salt; Mechanism; Chloride; Diffusion; Adsorption; Building construction; Cement; Concrete; Byggnadsteknik;

   Abstract : A hypothesis regarding the mechanism causing salt frost scaling on Portland cement-bound materials is described. It is assumed that deterioration is due to osmotic micro ice body growth, as has been previously proposed for frost deterioration of moisture-isolated specimens of cement-bound materials. READ MORE

4. 2. Frost-induced deterioration of concrete in hydraulic structures : Interactions between water absorption, leaching and frost action

   Author : MARTIN ROSENQVIST; Avdelningen för Byggnadsmaterial; []
   Keywords : Vattenbyggnader; Dammar; Betong; Cement; Vattenabsorption; Vattenmättnadsgrad; Nedbrytning; Frostbeständighet; Spjälkning; Makroskopisk islinsbildning; Urlakning; Synergi; Hydraulic structures; Dams; Concrete; Cement; Water absorption; Degree of saturation; Deterioration; Frost resistance; Spalling; Macroscopic ice lens growth; Leaching; Synergy;

   Abstract : Frost deterioration of concrete can result in severe consequences to the safety, durability and functionality of a structure since it impairs the strength of the concrete. Frost damage may occur to structures that are in contact with water and subjected to frost action. READ MORE

5. 3. Numerical models for degradation of concrete in hydraulic structures due to long-term contact with water

   Author : Daniel Eriksson; Anders Ansell; Richard Malm; Erik Nordström; Katja Fridh; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; degradation; deterioration mechanisms; hydraulic structures; air-entrained concrete; multiphase model; long-term moisture conditions; pore size distribution; freezing; partially saturated; finite element method; Civil and Architectural Engineering; Byggvetenskap;

   Abstract : The durability of concrete is of major concern in all types of concrete structures where the combined effect of exposure conditions and the type and quality of the concrete material usually determines the rate of degradation. Furthermore, there are synergy effects between different deterioration mechanisms, which means that the combined rate of degradation is higher than the sum of the individual rates of each mechanism. READ MORE

6. 4. Squat defects and rolling contact fatigue clusters - Numerical investigations of rail and wheel deterioration mechanisms

   Author : Robin Andersson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rail surface irregularities; rolling contact fatigue clusters; dynamic vehicle–track interaction; rolling contact fatigue; studs; squats; fracture mechanics;

   Abstract : Squat defects, a type of localised rolling contact fatigue damage appearing on rail surfaces with rail break as an ultimate consequence, have concerned infrastructure managers for the last couple of decades. In recent years similar types of defects—so-called studs—that are visually resembling squats, have started to appear. READ MORE

7. 5. Protection of Biomolecules by Antioxidants - Mechanisms and Applications

   Author : Carl Grey; Bioteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dG; antioxidants; mass spectrometry; Analytical chemistry; Analytisk kemi; Food and drink technology; Livsmedelsteknik; Bioteknik; Biotechnology; DNA; Oxidation; Protein; Fenton reaction;

   Abstract : Reactive oxygen species (ROS) consisting of various oxygen-based free radicals as well as other reactive non-radical species produced in O2-related metabolism or through other processes are involved in the oxidation of such vital biomolecules as DNA, proteins and lipids. The types of oxidation represented here are known to cause many different diseases and disorders in human beings, such as cancer, Alzheimer's disease and ageing. READ MORE