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Visar resultat 1 - 5 av 22 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Development of strength and heat of hydration of young concrete at low temperature : influence of granulated blast furnace slag, silica fume and limestone filler

   Författare :Monica Lundgren; RISE; []
   Nyckelord :;

   Sammanfattning : .... LÄS MER

3. 2. Thermal Crack Risk Estimation and Material Properties of Young Concrete

   Författare :Anders Hösthagen; Jan-Erik Jonasson; Mårten Larson; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Thermal cracking risk; young concrete; Equivalent Restraint Method; strength development; heat of hydration; creep; shrinkage; thermal dilation; modeling; field observations; Structural Engineering; Konstruktionsteknik;

   Sammanfattning : This thesis presents how to establish a theoretical model to predict risk of thermal cracking in young concrete when cast on ground or an arbitrary construction. The crack risk in young concrete is determined in two steps: 1) calculation of temperature distribution within newly cast concrete and adjacent structure; 2) calculation of stresses caused by thermal and moisture (due to self-desiccation, if drying shrinkage not included) changes in the analyzed structure. LÄS MER

4. 3. Chemical Properties of FBC Ashes

   Författare :Britt-Marie Steenari; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; straw ash; environmental impact of ash handling; sintering; deposits; fouling; wood ash recycling; FBC; ash leaching; ash chemistry; PFBC; forest fertiliser; ash hydration reactions; fuel additives; wood ash characteristics; CaS; ash melting; plant nutrient recycling;

   Sammanfattning : In this thesis several aspects of ash chemistry are discussed. An issue of primary concern for boiler operators is the formation of ash deposits. New biomass fuels are introduced, many of which have unfavourable ash melting behaviour due to high levels of alkali metal species and chlorine. LÄS MER

5. 4. Hydration, pore structure, and related moisture properties of fly ash blended cement-based materials : Experimental methods and laboratory measurements

   Författare :Oskar Linderoth; Avdelningen för Byggnadsmaterial; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cement; Murbruk; Betong; Hydratation; Porstruktur; Sorption; Fukttransport; Mineraliska tillsatsmaterial; Flygaska; Cement; Mortar; Concrete; Hydration; Pore structure; Water vapour sorption; Moisture transport; Supplementary cementitious materials; Fly ash;

   Sammanfattning : Cement-based materials, such as mortar and concrete, are the most employed construction materials in the world. Cement is an important component; it reacts with water to form a glue, called cement paste, which causes the material to harden. Today, cement production accounts for a significant portion of the world’s annual carbon dioxide emissions. LÄS MER

7. 5. Development of strength and heat of hydration of young concrete at low temperature - influence of granulated blast furnace slag, silica and limestone

   Författare :Monica Lundgren; Avdelningen för Byggnadsmaterial; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; låga temperaturer; värmeavgivning; betong; betonggjutning; hållfasthet; hydratation;

   Sammanfattning : The work presented in this licentiate thesis was carried out within the project task Use of industrial by-products and filler in concrete, part Early-age strength development at low temperatures in concrete with mineral additions/fillers. To improve the understanding and to increase the data available, the study investigated the development of compressive strength and heat of hydration while curing at 5°C compared with curing at 20°C. LÄS MER