A study has been made of the enhancement of the mechanical strength of bricks fabricated from five Sri Lankan Quaternary and post-Quaternary brick clays with the objective of identifying and optimising those factors which control the quality and performance characteristics of fired clay products of this type. Mineralogical investigations have shown that the clays are predominantly kaolinitic. Of the accessory minerals, feldspars and gibbsite are the chief constituents. The experimental programme involved the development of feasible processing techniques for clay bodies, the establishment of optimum heat treatments for their firing, and the testing and evaluation of material properties of the fired products. The microstructures of fired materials have been characterized using optical and electron microscopical techniques, as well as X-ray diffraction, electron probe microanalysis and chemical analysis. A limited study was also made of the durability of laboratory fired specimens. Methods of strength enhancement included use of the reactions of phosphates with natural clays, use of mineralizers to induce mullitization and surface coating by an efflorescence process. A kinetic analysis based on the first order kinetics is proposed for the estimation of optimum firing conditions for kaolinitic clays. The study has shown that surface coating of bricks increases the load at the elastic limit by up to 30% and the ultimate failing load by 19% in the clays examined. The measured increases in modulus of rupture and modulus of elasticity are over 33% and 40% respectively. A fabrication technique which requires the incorporation of phosphates has been developed. This provides the possibility of lowering the peak temperature of firing to 500°C. Flexural strength increase of up to 60% over the normally fired unbonded specimens can be achieved using this technique. Relevant compatibility relations in the ternary system Si02- P205-AI203 at 500'C are proposed. The presence of an optimum amount of mineralizer in a clay body may alter its sintering characteristics resulting in an increase in modulus of rupture up to 55%. However, uncontrolled additions exceeding 4 wt% cause deleterious effects. Microstructural analysis provides evidence that liquid phase sintering, development of mullite, development of pores and bloating are the dominant strength determining features in these clays. An empirical equation correlating the functional relation between modulus of rupture, mullite content and porosity is proposed. Mechanisms of strength development are discussed in the light of these findings.

Fly ash is a waste product from thermal power plants where pulverised coal is used for the generation of electricity. Fly ash is being utilised in the blended cements, additive for concrete and manufacturing of concrete blocks and bricks. Fly ash-lime-gypsum bricks are being manufactured and marketed throughout the country. The literature review on fly ash-lime-gypsum (FALG) mixtures as intended to manufacture bricks or blocks for masonry applications indicates several gaps in understanding the various aspects of the technology. The present thesis is an attempt to understand the behaviour of compacted stabilised fly ash mixtures for the manufacture of fly ash bricks and characteristics of masonry using such bricks. A brief introduction to the technology of compacted stabilised fly ash bricks for structural masonry is provided. Review of the literature on fly ash-lime and fly ash-lime-gypsum mixtures, and fly ash bricks is provided in chapter 1. Chapter 2 gives details of the experimental programme, properties of raw materials used in the experimental investigations, methods of preparing different types of specimens and their testing procedures. Chapter 3 deals with the strength and absorption characteristics of compacted stabilised fly ash mixtures in greater detail. The main focus of the investigations is on arriving at the optimum stabilizer-fly ash mixtures considering density, stabilizer-fly ash ratio, curing conditions, etc. as the variables. Therefore the parameters/variables considered in the investigation include: (a) density of the compacted fly ash mixture, (b) stabilizer-fly ash ratio, (c) curing duration (normal curing and steam curing) and (d) dosage of additives like gypsum. Some of the major conclusions of the investigations are (a) compressive strength of compacted stabilised fly ash mixtures is sensitive to dry density of the specimens and the strength increases with increase in density irrespective of stabiliser content and type of curing, (b) Optimum limefly ash ratio yielding maximum strength is 0.75, (c) addition of gypsum accelerates rate of strength gain for compacted fly ash-lime mixtures (d) for 28 days wet burlap curing optimum gypsum content yielding maximum strength is 2% and maximum compressive strength is achieved for lime contents in the range of 10 – 17%, (e) steam curing (at 80 °C for 24 hours) gives highest compressive strength for compacted fly ash-lime mixtures. Characteristics of compacted fly ash-lime, fly ash-lime-gypsum and fly ash-cement bricks and their masonry are presented in chapter 4. Compressive strength, elastic modulus, water absorption, initial rate of absorption, dimensional stability and durability of the bricks were examined. Compressive strength, flexure bond strength and stress strain relationship for the fly ash brick masonry using cement-lime mortar were evaluated. The investigations clearly show the possibility of producing bricks of good quality using compacted fly ash-lime gypsum mixtures. Wet compressive strengths of 8- 10 MPa was obtained for compacted fly ash-lime-gypsum bricks at the age of 28 days. Wet strength to dry strength ratio for these bricks is in the range of 0.55 – 0.67. Initial tangent modulus for the fly ash-lime-gypsum bricks in saturated condition is in the range of 8000 – 12000 MPa. There is a large scope for selecting optimum mix ratios of fly ash, sand, lime and other additives to obtain a specific designed strength for the brick. The thesis ends with Chapter 5 highlighting major conclusions of the investigations.

Ferrochrome slag is a by-product from the production of ferrochrome, an essential component in stainless steel. World wide it is known that ferrochrome slags are been used mainly in the road and civil construction industries, and in producing refractories. Slag management at ferrochrome producing companies has been influenced by the limited space available and financial cost implications of the siag dumps. In South Africa, according to the Department of Water Affairs and Forestry's minimum requirements, (DWAF, 1998), ferrochrome slag due to its quantity or volume on the disposal sites has been classified as hazardous, as it leaches Manganese (Mn) (33%) above the DWAF minimum environmental requirements acceptable levels. This rating of the slag has therefore put limitations on the use of slag commercially. This paper investigates the various slag uses proposed which can impact positively on the management of the slag i.e. that would reduce its dumping loads and consequently its impact on the surrounding environment. The uses proposed for are brick and concrete making and road building. The paper provides results for the proposed slag uses leaching potential, performs a risk assessment to determine its potential effect on the environment and human health as weli as discusses the method used to delist the slag through the South African delisting process. Comments on the process from the DEAT are also provided. / Thesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2009.

Ferrochrome slag is a by-product from the production of ferrochrome, an essential component in stainless steel. World wide it is known that ferrochrome slags are been used mainly in the road and civil construction industries, and in producing refractories. Slag management at ferrochrome producing companies has been influenced by the limited space available and financial cost implications of the siag dumps. In South Africa, according to the Department of Water Affairs and Forestry's minimum requirements, (DWAF, 1998), ferrochrome slag due to its quantity or volume on the disposal sites has been classified as hazardous, as it leaches Manganese (Mn) (33%) above the DWAF minimum environmental requirements acceptable levels. This rating of the slag has therefore put limitations on the use of slag commercially. This paper investigates the various slag uses proposed which can impact positively on the management of the slag i.e. that would reduce its dumping loads and consequently its impact on the surrounding environment. The uses proposed for are brick and concrete making and road building. The paper provides results for the proposed slag uses leaching potential, performs a risk assessment to determine its potential effect on the environment and human health as weli as discusses the method used to delist the slag through the South African delisting process. Comments on the process from the DEAT are also provided. / Thesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2009.

Orientador: Miguel Angel Ramírez Gil / Coorientadora: Maria Luiza Gonçalves Pereira / Banca: Elson de Campos / Banca: Fernando Vernilli Júnior / Resumo: Tijolos queimados de argila são muito usados na construção civil, porém consomem altas quantidades de energia durante o processo de queima. Tijolos de solo-cimento são uma alternativa a esses tijolos, pois dispensam a queima, reduzindo o consumo energético em sua produção. Por outro lado, possuem um problema relacionado com a produção de uma de suas matérias primas, o cimento, que envolve a liberação de alta quantidade de CO2 durante seu processo de fabricação, um gás amplamente discutido como um dos responsáveis pelo efeito estufa. Este trabalho teve como objetivo principal desenvolver e caracterizar (por meio de ensaios de flexão em três pontos e de absorção de umidade) amostras de solo-cimento com substituições de cimento em teores de 25%, 50%, 75% e 100% por cinza de casca de arroz e cal. Os resultados mostram que quanto maior o teor de substituição de cimento, maior é a perda de resistência mecânica das amostras. Entretanto, a resistência característica aumenta conforme o avanço das idades para uma mesma composição, sendo que aos 28 dias de idade as amostras com substituições de cimento em 0%, 25%, 50%, 75% e 100% obtiveram valores de resistência característica equivalentes a 10,81 MPa, 10,20 MPa, 8,97 MPa, 7,75MPa e 6,29 MPa respectivamente. Em termos absorção de água, apesar de identificado o aumento de seus valores conforme o aumento da substituição de cimento e também com o avanço da idade das amostras, todos os materiais foram aprovados em comparação com os requisit... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Burnt clay bricks are widely used in construction industry, but consume high amount of energy during the burning process. Clay-cement bricks are an alternative to these bricks as dispense burning, reducing the energy consumption in its production. However, they have a problem related to the production of one of its raw material, the cement, which involves the release of high amounts of CO2 during its manufacturing process, a gas responsible for the greenhouse effect. This work had as main study point to develop and characterize (by bending tests and water absorption) clay-cement samples with cement replacements in content of 25%, 50%, 75% and 100% by rice husk ash and lime. The results show that the strength reduces while the cement replacement is increased. On the other hand, the strength increases in function of time for the same composition. Therefore, at 28 days of age the samples with cement substitutions of 0%, 25%, 50%, 75% and 100% obtained 10.81 MPa 10.20 MPa, 8.97 MPa, 6.29 MPa and 7,75MPa respectively. In terms of water absorption, the amount of absorbed water was higher for the samples with higher age and lower cement content, but all the samples were approved compared to the requirements of ABNT 8491, which requires a maximum 20% of water absorption, being the highest value equivalent to 14.52% for the sample with 100% of cement substitution and 28 days of age. These values indicate the possibility of cement replacement by rice husk ash and lime, being the most a... (Complete abstract click electronic access below) / Mestre

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The bricks are one of the primary materials required for construction of homes that no used completely when executes all the walls due, the excess purchase, the cutting to be settle, the breaking for their transfer and its fixed dimensions; this situation requires monitoring on work site the order, cleanliness and accidents. A common practice is these bricks and/or waste are included in the clearing construction before being deposited or eliminated in dumps or sanitary landfills, with their early clogging and shortening them to ther design lifespan. An important alternative to reduce this waste, is to recycle them and reuse them as a concrete component material, due to their high absorption percentage that allows them to keep the water inside of them and then use it in the cement hydration process as internal curing of the concrete. In the present investigation, the effect of crushed clay brick as a replacement for coarse aggregate in concrete processing is studied. The results indicate that with 21 % replacement brick, the plastic contraction decreases, and the compressive strength and flexural strength increase.

The diploma thesis deals with the possibilities of using recycled brick as a component in the preparation of glazes. Recycled brick is a mixture of crushed bricks, it can also contain a brick tablecloth, its composition and color makes this material practically identical to a brick shard. Due to these properties, it can be assumed that recycled brick can be used to prepare technical glazes with a specific color. The aim of the diploma thesis is to verify the possibilities of using recycled brick for the preparation of technical glazes. For prepared glazes, then evaluate their properties and estimate for which type of product these alternative glazes could be used.

Lateritic soils which have been described as highly weathered tropical or sub-tropical residual soils with varying proportions of particle sizes ranging from clay size to gravel, were studied in an attempt to establish its suitability or otherwise as sustainable material in building bricks and housing developments that will meet the present challenge of sustaining the environment without costing too much and maintaining a high standard of strength, durability and aesthetics. Index properties of the lateritic soils tested revealed them as mostly well-graded, comprising both cohesive (silt and clay) and cohesionless (sand and gravel) soil fraction. The mineralogical analysis shows the presence of sesquioxides in the clay portion which were found to be very useful in the natural binding process as well as in the presence of a stabiliser (cement). The geotechnical analysis on the lateritic soil revealed a strong compressive strength with a relatively sound dry density which could guarantee a good durability in resulting bricks made from these soil materials. Further test on the strength and durability of compressed earth bricks (CEBs) made from these lateritic soils revealed a brick with compressive strength ranging between 6.33 and 15.57 MPa which are considered to be of very good strength coupled with its sound durability strength established over a period more than one year under different kinds of severe weather and seasonal conditions. In conclusion, sesquioxides presence and mineralogy of lateritic soils were found to be largely responsible for their good compressive and durability strength which made them good and sustainable materials for CEBs. / Thesis (PhD)--University of Pretoria, 2017. / Geology / PhD / Unrestricted

Frågan om ett nytt konstmuseum i Uppsala har varit under ständig debatt de senaste åren. Den 27 maj 2020 fattade kommunstyrelsen i Uppsala ett beslut om att lokalisera ett konstmuseum på antingen Uppsala slott eller kvarteret Kaniken. Uppsala står idag inför en stor förändring, där förutsättningarna för butiker förändras i takt med e-handeln. Det har hittills skett relativt obemärkt men har nu, inte minst under den pågående pandemin, på allvar blivit en faktor att räkna med och förhålla sig till. Platsen där projektet utgår ifrån är kvarteret Kaniken. Ett kvarter centralt placerat vid västra delen av Fyrisån. Byggnaderna i kvarteret har tidigare använts som tryckerilokaler för almanackor, men används idag främst som biosalonger för allmänheten. Lokalerna har bra förutsättningar för ljuskänslig konst, och i arbetet argumenteras om hur den befintliga byggnaden kan sättas in i en samtida kontext för ett nytt konstmuseum. / The question of a new art museum in Uppsala has been under constant debate in recent years. On 27 May 2020, the municipal board in Uppsala made a decision to locate an art museum at either Uppsala Castle or the Kaniken district.Uppsala is today facing a major change, where the conditions for stores change in step with e-commerce. It has so far happened relatively unnoticed but has now, not least during the ongoing pandemic, seriously become a factor to reckon with and relate to.The place where the project is based is the Kaniken neighborhood. A block centrally located at the western part of Fyrisån. The buildings in the block have previously been used as printing premises for almanacs, but today are mainly used as cinemas for the general public. The premises have good conditions for light-sensitive art, and the work argues about how the existing building can be placed in a contemporary context for a new art museum.