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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.
21

Bonboo

Wolters, Marit 17 November 2023 (has links)
Porenbeton ist ein Material, das zwischen Architektur und Natur eine direkte Verbindung schafft. Er lässt dem Menschen Raum für die Gestaltung, passt sich der vorgegebenen Gussform an, wächst innerlich jedoch nach seinen eigenen Regeln. Die Luftblasen im Material bilden ein zelluläres Gebinde mit unregelmäßiger Struktur. Während des Gießens der im Studio experimentell gemischten Betonmasse beginnt diese, sich aufzublähen, zu brodeln und zu zischen. Wie ein organischer Zellhaufen, der wächst und atmet. Das erzeugte Material ist leichter als Normalbeton und durch die experimentelle Arbeit oft fragil.
22

Studium vlivů ovlivňujících životnost cementobetonových krytů v ČR / Study of impacts affecting the lifetime of cement concrete coverings in the Czech Republic

Láznička, Josef January 2019 (has links)
This thesis deals with the study of cement – concrete coverings. The aim of the thesis is a summary of current knowledge of these constructions. The experimental part of this paper deals with the design of concrete for the lower layer of cement – concrete cover. Emphasis is placed on the elimination of microcracks and to increase the lifetime of these construction.
23

Fuktvandring i putsade lättbetong- och tegelfasader : En undersökning om hur fukt vandrar och beter sig mot en putsfasad av två olika material med olika porositeter. / Moisturetransport in aerated concrete- and brickfacades : A study of how moisture behave and transports in a facade of two different materials with different porosities

Hägg, Marcus, Sjölund, Henrik January 2013 (has links)
I dagsläget finns en stor mängd byggnader i Sverige där fasaden består av puts direkt anliggande mot antingen lättbetong eller tegel. Dessa fasader kan skapa problem för brukaren p.g.a. fukttransport via putsen direkt in i konstruktionen. Problemen som kan uppstå som följd av dessa konstruktioner är inte bara estetiska utan kan även påverka inomhusmiljön. Syftet med detta arbete var att undersöka om det gick att med ny teknik visa de resultat som framkommit från erfarenheter från praktiskt arbete samt undersöka hur en renovering påverkar de fasader som består av puts direkt mot lättbetong eller tegel. Arbetet har utförts med hjälp av simuleringsprogrammet Wufi Pro för att sedan analyserats med hänsyn till fukttransporter och vatteninnehåll. Resultaten som framkommit påvisar en förhöjd risk för problem med de ursprungliga fasaderna samt slutsatsen att en renovering enligt ett av de två förslagen är att föredra. / Today there’s a great deal of buildings in Sweden where the facade is constructed by plaster directly connected to either aerated concrete or masonry brick. These facades could create problems for the user on accord of the moisture transport via the plaster directly into the construction. The problems that could follow these types of facades aren’t just esthetical but could also affect the indoor environment. The purpose with this study was to examine if it would be possible using today’s technology to show the results coming from past experiences by practical work, and at the same time examine how a remodel affects the facades that consists of plaster directly on aerated concrete or masonry brick. The work has been conducted with the simulation program Wufi Pro, later to be analyzed  according to moisture transport and water content. The results that came from this has shown an increased risk for problems with the original facades and at the same time that a remodel according to one of the two proposed remodel ways to prefer.
24

[pt] AVALIAÇÃO DO COMPORTAMENTO MECÂNICO DE PAINÉIS SANDUÍCHE COM COMPÓSITOS LAMINADOS REFORÇADOS COM FIBRA DE CURAUÁ E NÚCLEO DE CONCRETO CELULAR AUTOCLAVADO / [en] EVALUATION OF THE MECHANICAL BEHAVIOR OF SANDWICH PANELS WITH CURAUÁ FIBER-CEMENT COMPOSITE LAYERS AND AUTOCLAVED AERATED CONCRETE CORE

ISABELA DE PAULA SALGADO 19 December 2019 (has links)
[pt] O presente trabalho propõe-se a analisar o comportamento mecânico de painéis sanduíche constituídos por duas camadas externas de compósitos cimentícios reforçados com fibras naturais, separadas por um núcleo de concreto celular autoclavado (CCA). Cada placa de material compósito foi moldada diretamente sobre a superfície de um bloco de CCA, por meio da disposição manual de três camadas unidirecionais de fibras longas de curauá. Visando prover maior durabilidade ao compósito, desenvolveu-se uma matriz com baixo teor de hidróxido de cálcio, substituindo uma parcela do cimento por materiais pozolânicos. Ensaios de caracterização da matriz, dos filamentos de curauá e dos blocos de CCA foram realizados para a obtenção de suas propriedades independentes. Os compósitos foram submetidos a ensaios de arrancamento do tecido, tração direta e flexão a quatro pontos para a avaliação de diferentes aspectos de seus mecanismos de fissuração, resistência e capacidade de deformação. Zonas de carregamento foram indicadas em cada caso para demonstrar o comportamento padrão dos compósitos. Os painéis sanduíche, por sua vez, foram analisados em termos de interface, por meio de ensaios de aderência e micrografias da superfície de transição dos materiais, e de desempenho mecânico, por ensaios de flexão a quatro pontos cíclicos e monotônicos. Esses últimos forneceram a rigidez, capacidade de carga e deflexão dos painéis sanduíche, tal como as principais propriedades de seus elementos: para o núcleo, a resistência ao cisalhamento e o módulo de cisalhamento, e para as lâminas, a resistência à compressão e à tração. Os ensaios cíclicos testaram a resistência do material a séries de carregamento-descarregamento, enquanto ensaios de aderência foram utilizados para verificar a interface entre os compósitos laminados e o núcleo de CCA. Os resultados indicaram um desempenho satisfatório dos painéis sanduíche, uma vez que os compósitos foram capazes de lhes fornecer um comportamento de strain/deflection hardening, aumentando sua resistência e tenacidade. A adesão entre lâminas-núcleo mostrou-se eficaz, de maneira que os diferentes materiais compreendidos demonstraram interação adequada entre si, bem como propriedades complementares. Dentre os objetivos desse trabalho, encontra-se o desenvolvimento de um material sustentável, leve, resistente e tenaz, de modo que constitua uma alternativa promissora e de baixo custo a aplicações de Engenharia. / [en] This present work aims to analyze the mechanical behavior of sandwich panels consisting of two outer layers of natural fiber-reinforced cementitious composites separated by a core layer of autoclaved aerated concrete (AAC). The molding of each composite layer was made directly on the surface of an AAC block, by manually arranging three layers of long unidirectional aligned curauá fibers in the mortar. In order to increase the composite durability, a matrix with a low content of calcium hydroxide was developed, where the Portland cement was partially replaced by pozzolanic materials. Characterization tests of the matrix, the curauá filaments and the AAC blocks were performed to obtain their independent properties. The composites were submitted to fabric pull-out tests, direct tensile tests and four-point bending to evaluate different aspects of their cracking mechanisms, strength and deformation capacity. Loading zones were indicated in each case to demonstrate the standard composite behavior. The sandwich panels, on the other hand, were analyzed in terms of interface, through pull-off tests and SEM images of the materials transition surface, and mechanical performance, by means of cyclic and monotonic four-point bending tests. The latter registered the rigidity, load capacity and deflection of the sandwich panels, as well as the main properties of their elements: for the core, shear strength and shear modulus, and for the skin layers, compressive strength and tensile strength. Cyclic tests evaluated the resistance of the material to loading-unloading cycles, while pull-off tests were used to verify the interface between the laminated composites and the AAC core. The results indicated a satisfactory performance of the sandwich panels, since the composite layers provided a strain/deflection hardening behavior to the material, increasing its flexural strength and toughness. The adhesion between the layers and the core proved to be effective, so that the comprised materials displayed adequate interaction between each other, as well as complementary properties. Among the objectives of this work is the development of a sustainable, lightweight, resistant and tough material, in a way that it represents a promising and low-cost alternative to Engineering applications.
25

Možnosti využití kameniva na bázi odpadní skleněné moučky v novodobých stavebních materiálech / Possibilities of utilization of aggregate based on glass powder in new building materials

Novák, Jakub January 2018 (has links)
The diploma thesis deals with the use of waste glass powder as an aggregate in thermal insulation plasters for AAC. In the theoretical part, the problem of thermal protection of buildings is discussed first. The production and properties of foamed glass are described. Then the research of plasters, their composition and properties was made. Thermal-insulating plasters are specified and their use has been proposed for thermal insulation of building structures. In the practical part, suitable formulations have been proposed in the form of dry plaster and mortar mixtures (SOMS). Test samples were prepared from them. The physical and mechanical properties were measured. These were compared with the requirements set by standards and technical regulations. To get closer to the behavior of plasters on real buildings an AAC wall was built. The individual recipes were applied on it. It was monitored working with plaster and how it held on the masonry. During ripening crack development was observed. Optimization calculation inculded these aspects and it determined the optimal recipe. All designed recipes can be used as a thermal-insulating plasters.
26

Gelový infuzní clonový systém pro dodatečnou hydroizolaci různých druhů zdiva s využitím druhotných surovin / Gel infusion screen system for additional waterproofing of various types of masonry with share of secondary raw materials

Melichar, Jindřich Unknown Date (has links)
Virtually any construction project in our climate zone is facing some form of moisture. Older and historical buildings are mostly affected by the negative impact of water. Previously, the additional reduction of the moisture was executed only by mechanical methods, pushing insulating sheets or breaking through and cutting of masonry. Over time chemical methods were also invented, which are compared to the mechanical considerably simpler and user friendly applications to statics of treated buildings, making them ideal for the treatment of historical buildings or buildings that would not bear significant disruption. The main principle of chemical methods of redevelopment of wet masonry is the application of special material into the line of drilled holes with a given pitch. Subsequent penetration of the grouting material is believed to intersect an arc of individual drill holes, and thus to create so-called grout curtain that prevents the accumulation of water above it. Injection material may also contain a proportion of secondary raw materials, thereby reducing the influence of the impact of production on the environment. Efficiency infusion materials in masonry affected by many factors, such as temperature, humidity, or the type of material treated. It is also an important factor to determine the effectiveness of the remediation of the material, proving its ability to penetrate the building material by identifying its presence in it.
27

Vývoj vysokohodnotného pórobetonu při využití alternativních zdrojů / Development of high quality autoclaved aerated concrete using alternative resources

Kostura, Patrik January 2019 (has links)
With the growing trend of construction, the demand for building materials is growing steadily. Porous concrete is widely used in the building industry, that makes efforts to discount production and simultaneously save the environment. The aim of this thesis is to develop high-quality porous concrete by using alternative raw materials as a substitute for silicate sand. As a possible substitute were chosen: Silica masonry, foundry sand and fireclay boulders. The influence of two key parameters - the specific surface (130, 240 and 350 m2·kg-1) and the amount of silica sand substitution (10, 30 and 50 %) were monitored. Two autoclaving modes (7 and 12 hours of isothermal durations at 190 ° C) were tested. Based on the physico-mechanical and mineralogical characteristics of the porous concrete composites was chosen the ideal surface area of 240 m2·kg-1 and time of isothermal endurance was determined at 7 hours (temperature 190 ° C, pressure 1,4 MPa). From the optimal intentions were created samples with a macroporous structure, using an aluminum powder. Physical-mechanical properties and microstructural analysis (XRD, SEM) were subsequently determined on the samples. Ideal recipes were proposed with 50% sand substitution of fireclay boulders and 10% substitution of foundry sand. This was due to a 10% higher compressive strenght and an increase of the coefficient of constructiveness, compared to the reference sample.
28

Komunitní centrum pro seniory / Community Center for Seniors

Fišarová, Jana January 2020 (has links)
The subject of my diploma thesis is a proposal of a new community center for seniors near Brno in the village Pravlov. The building is designed for 12 people in 11 separate housing units. The building is divided into three floors. On the ground floor there are civic amenities (doctor's office, hairdresser) and technical facilities (utility room, cleaning room, facilities for employees). On the second and third floors there are separate apartments 1 + 1 and 1 + kk. Vertical walls are made of aerated concrete blocks, horizontal structures are made of reinforced concrete monolithic ceiling structures. The vertical connection between the individual floors is created by a prefabricated staircase. The community center for seniors is covered by a vegetation roof and part of the building is covered by a flat roof. On the south side of the building is located balcony.
29

Novostavba polikliniky v Rousínově / Newly-built polyclinic in Rousínov

Galata, Jindřich January 2020 (has links)
The subject of this diploma thesis is design documentation for implementation of the construction applied on the newly-built polyclinic in Rousínov. The polyclinic is the detached one, placed in the flat building plot with adjacent parking lot. The whole building is solving continuity on the surrounding local roads and dispersion areas. Basement of this building serves primarily as technical facilities for properly working on this new building. For example it’s about storages, utility room, boiling room, mechanical room etc. The first above-ground floor, where is situated entrance in to the building, from the southeast, is placed pharmacy, medical transport service and the first one doctor’s surgery. In the other above-ground floors are placed another doctor’s surgeries every with different specialization and in the last floor is a section for managers of polyclinic. The building is designed as a cast-in-place concrete frame with infill walls from aerated concrete. This building is based on plain concrete foundation pads and in the middle of span is shear core. Horizontal structures are solved by point-supported slabs with periphery beam and roofing is solved by warm flat roof. Whole building is insulated with contact thermal insulation from non-flammable material.
30

Návrh technologie vodopropustných betonů / Technology design watertight concrete

Skřivánek, Michal January 2017 (has links)
My work describes technology design of pervious concrete. The theoretical part contains a research about this kind of concrete usually from foreign authors. In general, I focused on the composition of the PC, aggregate grading curve, behaviour of concrete in fresh state, storing and compaction of concrete. A critical part is the aggregate grading curve – it plays the main role in the final level of water permeability. Further, we will go through the real world scenarios where we can use this type of concrete and also through the associated drawbacks. A substantial part of this work is about development of water-permeability test. The practical part shows variety of recipes with a list of measured and observed characteristics (compressive strength, frost resistence and water-permeability). The conclusion includes evaluation of the results and suggestions for future development in this area.

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