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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Limes, mortars, and cements

Emerson, Cyrus H.. January 1876 (has links) (PDF)
Thesis--University of Missouri, School of Mines and Metallurgy, 1876. / The entire thesis text is included in file. Holograph [Handwritten and illustrated in entirety by author]. Title from title screen of thesis/dissertation PDF file (viewed August 19, 2008)
2

Limes, mortars, and cements

Alexander, Curtis. January 1884 (has links) (PDF)
Thesis--University of Missouri, School of Mines and Metallurgy, 1884. / The entire thesis text is included in file. Holograph [Handwritten in entirety by author]. Title from title screen of thesis/dissertation PDF file (viewed October 27, 2008)
3

Conservation and seismic strengthening of architecutural heritage : Byzantine churches of the ninth till the fourteenth centuries in Macedonia

Sumanov, Lazar January 1999 (has links)
No description available.
4

Development of bond strength in hydraulic lime mortared brickwork

Zhou, Zhaoxia January 2012 (has links)
The first recorded use of hydraulic lime in construction can be traced back to at least two thousand years ago. Hydraulic lime, produced through either adding pozzolanic materials or calcining clay containing limestone, unlike air lime, can set and harden under water, developing strength through initial hydration reaction and subsequent carbonation. After WWII Portland cement mortars had almost completely replaced lime based mortars in modern construction. However, through conservation and specialist construction the benefits of hydraulic lime are becoming increasingly recognised. To support wider usage of these mortars there is a need for systematic study on the mortar properties and structural performance of lime mortared masonry. This thesis presents findings from a research programme conducted to develop understanding of the mechanical properties of natural hydraulic lime (NHL) mortared brickwork. The work focussed on the flexural strength of NHL mortared brickwork. A variety of material and environmental factors, including lime grade and supplier, mix proportion, sand type and age, have been investigated. In addition the research has completed an in-depth study on the influence of brick absorption characteristics on bond development. The two methods of flexural wall panel and bond wrench testing to establish flexural strength have been compared. In addition to flexural strength, initial shear strength and compressive strength of brickwork has also been investigated. A greater understanding of NHL mortared brickwork performance has been developed through this work. Performance of the brickwork has been related to properties of constituent materials and environmental factors. Recommendations for design performance of materials have been provided.
5

Constructing lordship in North Atlantic Europe : the archaeology of masonry mortars in the medieval and later buildings of the Scottish North Atlantic

Thacker, Mark Anthony January 2017 (has links)
This thesis investigates the archaeological potential of masonry mortars throughout North Atlantic Europe, with a particular focus on the buildings and environments of medieval northern and western Scotland. The results of an extensive non-intrusive survey of medieval and later buildings are presented, within which nine multiphase sites were subject to more comprehensive building, environment and materials analysis. The survey suggests that, in general, different mortar-making techniques had well-defined sub-regional distributions which are not simply a correlate of environmental availability, but developed in different ways over time. Moreover, all of the more comprehensively studied buildings contain evidence of striking material contrasts from phases to phase which has great potential in standing building analysis. Material contrasts in masonry evidence between building phases, between neighbouring buildings, between specific buildings and the regional corpus, and between the regions themselves, are then considered as evidence of changing cultural, chronological and environmental context. The relationship between secular and ecclesiastical buildings across the region is a particular concern. Qualitative lab-based and on-site material interpretations made throughout the thesis are supported by a programme of comparative experimentation. This thesis includes the first comprehensive investigation of lime mortars made from marine shells, the first evidence of lime mortars made from coralline algae, results from the first programme of dating medieval buildings in Scotland through radiocarbon analysis of relict mortar fuel, and microstructural analysis of a large range of medieval mortars from Norway to the Isle of Man. Wider research considers the initial emergence of mortared masonry in North Atlantic Europe and the relationship between clay and lime mortars. Ultimately, by placing the upstanding buildings archaeology at the centre of the medieval and later landscape this thesis will demonstrate that masonry mortars have significant potential to inform our understanding of the cultural and environmental context of lordship construction in the North Atlantic, providing a new focus for further interdisciplinary discourse.
6

Traditional lime mortar and plaster : Reconstruction with emphasis on durability

Balksten, Kristin January 2007 (has links)
Lime mortar and plaster have been investigated with the aim to improve the knowledge on how to make them as durable as before the cement technology was developed. The background was the durability problems experienced for newly produced lime plaster on the medieval churches on the island of Gotland, Sweden. In some cases the new lime plaster façades showed severe frost damages after only one winter. Although the lime was burnt and produced according to old local traditions, the lime mortar was still mixed and worked onaccording to methods developed for lime-cement mortar. This often led to a very porous lime plaster with a lime shell in the surface and such a plaster has been shown to be sensitive to frost expansion. Field studies were combined with laboratory studies of thin section specimens. Optical microscopy and scanning electron microscopy have been important analytical methods showing the porosity and the structure of the binder and aggregate materials. The investigations have been carried out on both historic and on newly made reference mortar and plaster. The field studies were carried out mainly on Gotland, using local materials. The influence of the raw materials, i.e. lime, aggregate and blending ratio was investigated. The focus has been on the workability of the fresh mortars as well as the pore structure of the carbonated plaster. The craftsmanship, meaning mixing and application of mortar and working the plaster surface, was studied in order to clarify its final pore structure. The pore structure in a material determines many of its technical properties, such as moisture transportation, compressive strength, permeability and frost resistance. All these properties are closely connected to the durability of the mortar and plaster. The permeability of the plaster has an impact also on the durability of the covered construction materials. Behind low-permeable plasters made with hydraulic binder, examples of extensive damages of rotten wood and leached lime have been shown. The investigations have shown the importance of choosing a mortar adjusted to the building construction. They also showed the importance of choosing a blending ratio adjusted to the specific binder and sand used in order to get a mortar with a suitable pore structure and good durability. It has also shown the importance of knowing when and how to work on the plaster surface in order to obtain a homogenous material that is well receptive for lime wash and has a good frost resistance. The combination of all the investigations has led to a method for reconstructing historic mortar and plaster with good durability.
7

Omítky modifikované příměsí pálených jílů / Plasters modified by burnt clays

Soukupová, Eva January 2015 (has links)
The doctoral thesis deals with the reactivity of burnt clays in connection with modified lime mortars. The theoretical part of the doctoral thesis provides an overview of the properties of lime mortars, their quality and ways of their degradation. The different types of burnt clays (brick powder, bentonites and burnt clay shale), their origin, properties and factors affecting their reactivity and methods of its evaluation are stated. The properties and reactivity of burnt clays are evaluated on the basis of determination of pozzolanic activity, mineralogical and chemical composition, surface area, density, content of the amorphous phase and granulometry in the experimental part of the doctoral thesis. The compositions of lime mortars containing burnt clays and evaluation of an impact of burnt clay on the properties of mortars in the fresh and hardened state are given. Consistency, bulk density, workability and air content of mortars in the fresh state are evaluated. Strength characteristics depending on the time, water absorbability, porosity, capillary attraction, adhesion, coefficient of diffusion resistance, frost resistance, shrinkage, mineralogical composition and microstructure of mortars in the hardened state are evaluated. Attention is also paid to the influence of the cellulose ether addition into the modified lime mortars.
8

Karbonatisering av modernt kalkputs med hydraulisk inblandning / Carbonation of modern lime mortar whith hydraulic mix

Hossainy, Shokoufeh January 2022 (has links)
Kalkbruk har använts i tusentals år som byggnadsmaterial i byggkonstruktioner.Senare, under 1800-talet, började en variant av hydraulisk kalk, kallad vattenkalk, att användas. Det hydrauliska kalkbruk som används idag i byggnadskonstruktioner såsom fasadmurning, putsning, fogning av murverk har blivit mer vanligt att använda i stället för cementbruk, eftersom det finns fler fördelar med kalkbruk som har hydraulisk inblandning än med det cementbaserade bruket. Kalkbruk används särskilt till renovering av äldre byggnader där kalk eller hydrauliska kalkbruk sedan tidigare har använts. Det hydrauliska kalkbruket utvinns från kalksten men den hydrauliska kalk som bränns av oren kalksten kallas naturligt hydraulisk kalk och tillverkas av Saint-Astier i Frankrike. Kalken har inga hydrauliska tillsatsmedel som cement, gips, flygaska eller puzzolana material. Enligt SS-EN 459–1:2015 klassas den naturliga hydrauliska kalken efter hållfasthet, och tillverkas i tre klasser: NHL 2, NHL 3,5 och NHL 5.Naturliga hydraulisk kalkbruken har för- och nackdelar, Produktens fördelar avses av de som använder bruket överväga nackdelarna. NHL-bruk passar bättre i fuktiga miljöer, det kan återanvändas, är miljövänligt, rent och naturligt, tål mer påfrestningar och driftstiden är mindre. Bakgrunden till arbetet är att NHL-bruks användning har blivit allt vanligare under de senaste decennier vid renovering av äldre kalkputsade byggnader. Väderförhållande och temperatur är av stor betydelse för att ha ett hållbart resultat inom kalkputsarbetet och således kan orsaka en viss försening i tidplaner och byggtider. Emedan nya metoder ska utreda och utvärderas för att få det optimala resultatet.Litteraturstudier, laboratorietester och intervjuer har använts för att kunna nå examensarbetets mål. Flera små tester har gjorts för att undersöka karbonatiseringsprocessen under olika väderförhållandet. Testerna visar att det naturliga kalkbruket karbonatiserar bättre och snabbare i en fuktig miljön, vilket passar det klimat som råder i Norden och i kustklimat. Det naturliga hydrauliska kalkbruket är dock ett material som kräver mer erfarenhet för att kunna uppnå bästa resultat för detta ändamål. Att vädret har stort betydelse för karbonatiseringsprocessen är ett resultat som framkommit i tidigare studier och forskning, vilket också de tester som utförts under detta arbete visar. Arbete med hydrauliska kalkbruk bör därför ske under perioder som passar kalkputsarbetet för att det ska hinna karbonatisera innan det riskerar att utsättas för påfrestning. En lämplig period är därför maj till oktober som den bästa perioder för kalkputsarbete.Naturliga hydrauliska kalkbruk utvecklas kontinuerligt, vilket kan bidra till att de kan ersätta det cementbaserade kalkbruket i framtiden utan några negativa konsekvenser såsom frostsprängning och låg hållfasthet. / The aim of the work was to analyze the carbonation of modern lime plaster with hydraulic mixing. Requirements for a certain carbonation can cause delays in schedules and construction time. The hydraulic lime mill is obtained from limestone, while the hydraulic lime burned by crude limestone is called natural hydraulic lime, which is manufactured by Saint-Astier in France. the lime has no hydraulic additives such as cement, plaster, fly ash or puzzolana materials. Natural Hydraulic lime mills fit better in the humid environment, it can be reused, is environmentally friendly, is clean and natural, can withstand more stress and the operating time is less. During the work, a study visit was made to an ongoing work process at Elin Wägnerskolan in Växjö, which Karlssons fasad AB had taken over the restoration responsibility. Interviews were conducted with one of the players at Målarkalk AB, which is one of the largest suppliers in the lime industry and project manager at Karlssons Fasad AB. Several small tests have been done to see the carbonation process under different weather conditions. The tests show that natural lime farming carbonates better and faster in a humid environment, which suits the Nordic countries and coastal environments. Natural hydraulic lime mills are well suited to replace cement-based mortars in the future without any negative impact.
9

Kalkbrukstraditioner i ekonomibyggnaderna på norra Gotland : Från Lärbro till Fårö / Lime mortar traditions in the agricultural buildings in northern Gotland : From Lärbro to Fårö

Elsetrønning, Vanja January 2022 (has links)
Under den andra stenbyggnadsperioden på Gotland började bönderna på landsbygden att bygga sina hus utav sten. De hade egna stenbrott där de kunde bryta både byggnadssten och sten till kalkbränning. Stenen brände de i milor eller husbehovsugnar. Även ekonomibyggnaderna uppfördes i sten på Gotland, detta är unikt i ett svenskt och nordiskt sammanhang. Murbruksprover från tio ekonomibyggnader har samlats in, alla gårdarna belägna i det stora kalkstensbältet på norra Gotland. Området är intressant att studera eftersom kalkbruksindustrin växte sig så stor här. En okulär besiktning av murbruksproverna i fält har genomförts, där provets kulör noterats och murbrukets innehåll av exempelvis sand och kalkklumpar med mera beskrivits. Det har tillverkats tunnslip av murbruksproverna för att på djupet kunna analysera dess innehåll och sammansättning. Genom analyserna kan vi spåra hur kalkbrukstraditionerna sett ut ute på landsbygden och vilka lokala traditioner som finns. Resultatet visar att stenen från Lärbroområdet har varierande kvalitet och egenskaper, där både ren och mer eller mindre oren sten bränts och nyttjats i kalkputs och kalkfärg. Stenen har gett ett kalkbruk med vissa orenheter i kalkpastan och inslag av ballastbildande hydrauliska korn, som inte gett bruket andra egenskaper än att det kan räknas som ett luftkalkbruk. Denna kalken är karakteristisk för gården i Vägume, där även en svagt hydraulisk kalk har dokumenterats. Denna har man dock behövt torrsläcka för att kunna göra bruk av den. En grynig luftkalk i vissa fall med inslag av hydrauliska ballastkorn ses också i bruksproverna från Hägvide i Lärbro, Stora Ire i Hellvi och vid Lunderhage i Fleringe där även ren kalkpasta använts. Gotland är känd för sin rena feta luftkalk, så som kan ses i proverna från Risungs i Rute, Gaustäde i Bunge och på Fårö. Det är därför intressant att se att svagt hydraulisk sten använts på Gotland och att de som haft tillgången till denna stenen lärt sig använda den. Hydraulisk kalk fanns även i ett av bruksproverna från Angelbos, denna var starkt hydraulisk och skulle kunna vara ett KC-bruk, eftersom de hydrauliska partiklarna näst intill är glasartade så som klinker. Blandningsförhållandet ligger generellt på 1:2 men även magrare och kalkrikare bruksblandningar förekommer i de undersökta proverna. Proverna är förhållandevis kompakta. I Rute och Bunge har man blandat fetare bruk, de flesta bruksproverna visar ett blandningsförhållande omkring 1:1, vissa något magrare. I Bunge påträffades troligen ett medeltida bruk, det var mycket kalkrikt, innehöll lite sand och många kalkklumpar som delvis bildade ballast. Fetare än 1:1. Det är en kalk som lagrats över länger tid och kan mycket väl ha jordsläckts. Denna traditionen ser vi inte i de andra bruksproverna där kalken släckts och använts direkt. Ballasten i näst intill samtliga bruksprover är mycket finkornig, omkring 0,5 mm och mindre. Inslag av större sandkorn förekommer med även dessa är små. Kalkklumparnas storlek varierar mycket från mm stora korn till 1 cm. De största mellan 2 – 3 cm. Ett modernare inslag och förhållningssätt till bruksblandning påträffades vid Risungs i Rute. Här har luftporbildare tillsatts vilket resulterat i ett bruk med ett kollapsat porsystem som ger dålig beständighet. Kontrasten är stor jämfört med de äldre feta och kompakta 1:1 bruken från Risungs.  Två av proverna innehöll större mängd lera. I provet från Vägume kommer lerinnehållet troligen från sanden som i delar av området är rik på lera, det är det enda provet som kan räknas som ett lerblandat kalkbruk i studien. Detta visar att även sanden kan skilja rätt mycket lokalt inom ett litet område som i sin tur ger bruk med olika egenskaper. I provet från Hägvide ses inslag av tegelröda partiklar som kommer av lerlager i den brända kalkstenen. Den tegelröda kulören kommer av att leran innehåller järnmineraler. I spritputsen har enbart kalk och naturgrus nyttjats, vilket är något ovanligt eftersom det gärna tillsätts lite sand även i spritputs. Det skulle kunna bero på att kalken i sig bidrar med ballast i form av kalkklumpar som gjort att sanden setts på som onödig. En regional variant som setts i flera av de analyserade bruksproverna. Studien visar att lokala material använts under den andra stenbyggnadsperioden på Gotland och att stenförekomsten har lokala variationer i och mellan socknarna, vilket gör att lokala traditioner kan utskiljas. Sanden är i större utsträckning av samma typ i de undersökta områdena, medans det i Vägume nyttjats både lerblandad sand och ren finkornig sand. Blandningsförhållandet generellt är omkring 1:2 vilket överensstämmer det nationala förhållningssättet som kom utöver 1700-talet. Så sätt skiljer sig Risungs och Gaustäde ut där traditionen för något fetare kalkbruk levt kvar. Vägumes lokala tradition där svagt hydraulisk kalk och grynig kalk med inslag av hydrauliska partiklar använts är därför intressant. / During the second stone building period on Gotland, the farmers in the countryside began to build their houses out of stone. They had their own quarries where they could mine both building stone and stone for lime burning. They burned the stone in lime kilns or household furnaces. The agricultural buildings were also built in stone on Gotland, this is unique in a Swedish and Nordic context. Mortar samples from ten agricultural buildings have been collected, they are all located in the large limestone belt in northern Gotland. This area is interesting to study because of the expansion in the lime industry here. An ocular inspection of the mortar samples was carried out during the field studies, where the colour of the sample was noted as well as the mortars content of, for example sand and lime lumps etc. Thin sections were made from the mortar samples in order to be able to analyse its content and composition. Through analysis we gained knowledge about the lime mortar traditions in the countryside and their local traditions.   The results shows that the stone from the Lärbro area has varying quality and properties, where both clean and more or less impure stone was burned and used in lime render and lime wash. The stone has given us a lime mortar with certain impurities in lime paste and elements of hydraulic grains forming aggregate. This type of lime is characteristic for the studied area in Vägume, where a sub hydraulic lime also where documented. The sub hydraulic one would have to be dry slaked in order to use it in mortar. A grainy lime in some cases with elements of hydraulic grains is also seen in the mortar samples from Hägvide in Lärbro, Stora Ire in Hellvi and at Lunderhage in Fleringe where pure lime paste also were used. Gotland is known for its pure and lime rich slime, as can be seen in the samples from Risungs in Rute, Gaustäde I Bunge and at Fårö. Its therefore interesting to see that sub hydraulic lime has been used on Gotland. Hydraulic lime was also found in one of the samples from Angelbos, where the amount of hydraulic binder was high, it could in fact be a KC-mortar, the hydraulic particles remind of clinker. The mixing ratio is generally 1:2, although leaner and more lime rich mortars occur in the examined samples. The mortars are relatively compact. In Runte and Bunge, the lime mortars appear to be fatter, most of the samples show a mixing ratio of around 1:1, some slightly leaner. In Bunge, a medieval mortar was probably found. It was extremely lime rich, containing little sand and many lumps of lime which partly formed aggregate. Fatter than 1:1. The lime that’s been used in this mortar has been stored for a long time and were probably earth slaked. We do not see this tradition in the other mortar samples where the lime was slaked and used directly. The aggregate in almost all of the mortars is very fine-grained sand, with a grain size around 0,5 mm and smaller. Elements of larger sand grains occur. The size of the lime limps varies greatly from mm-sized grains to 1 cm. The largest between 2-3 cm.  A more modern element and approach to traditional lime mortar was found in one of the samples from Risungs in Rute, where air entraining agent has been added. Resulting in a mortar with a collapsed pore system that gives the mortar poor durability. The contrast I great compared to the older lime rich and compact 1:1 mortars from Risungs.  Another interesting result showed that two of the samples contained larger amounts of clay. In the sample from Vägume the sand itself contained clay, which can be seen in parts of the area. This is the only clay-mixed lime mortar in the study. This shows that even the sand can differ quite a lot within a small area, which in turn produces mortars with different properties. In the sample from Hägvide, elements of brick-red particles can be seen in the thin section. This comes from layers of clay in the burnt lime stone. The brick-red colour comes from a clay containing iron minerals.  In the type of lime render that creates a granulated surface, only lime and see gravel have been used, which is somewhat unusual because a little amount of sand is often added. Maybe the sand was seen as unnecessary because the lime itself contributes with aggregate through the lime lumps. A regional variant seen in several of the analysed mortar samples.   The study shows that local materials were used during the second stone building period on Gotland, and that the stone that’s been used has local variations within and between the parishes, which means that local traditions can be distinguished. The sand is to a greater extent of the same type in the investigated areas, while in Vägume both clay-mixed sand and pure fine-grained sand were used. The mixing ratio is generally around 1:2, which corresponds to the national approach that came beyond the 18th century. This is how Risungs and Gaustäde stands out, where the tradition of somewhat fatter lime mortar has survived. Vägumes local tradition where sub hydraulic lime and gritty lime with elements of hydraulic particles were used is therefore interesting.
10

A study of carbonation in non-hydraulic lime mortars

Lawrence, Robert Michael Heathcote January 2006 (has links)
Lime has been used in construction for millennia, and its value, especially in the field of conservation architecture, has only recently been rediscovered. Lime mortars harden through carbonation, and this thesis is a study of that process. The research conducted has resulted in the development of two novel techniques for the measurement and detection of carbonation. The first technique is a method of thermogravimetric analysis which allows the carbonation profile to be measured within an acceptable time-frame. The second technique is the use of drilling resistance measurement to visualise the carbonation profile. The potential of elemental analysis to measure the carbonation profile has also been identified. It has been demonstrated that the lime/water ratio has less impact on the compressive strength of air lime mortars than had previously been supposed. The change in the pore size distribution of air lime mortars caused by carbonation has been studied, and a theory has been proposed to explain this phenomenon. Five different forms of air lime binder were studied. The impact of these on the structural performance of the resultant mortars has been assessed. It was concluded that mortars made with lime putties perform better than mortars made with dry lime hydrate. Mortars made with dispersed hydrated lime appear to perform as well as mortars made with lime putties, but at a slower rate of strength growth. The use of extra mature lime putty does not appear to confer structural performance benefits when compared with ordinary lime putty. It has been shown that the use of calcitic aggregates can produce air lime mortars which perform as well as moderately hydraulic lime mortars. It is theorised that this phenomenon is not directly related to carbonation, but rather to a complex interaction of the granulometry, mineralogy, chemistry and porosity of the aggregate with the binder.

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