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Islam, Md Shahidul. "Evaluation of lightweight aggregates in chip seal." Thesis, Kansas State University, 2010. http://hdl.handle.net/2097/7034.
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Master of Science<br>Department of Civil Engineering<br>Mustaque A. Hossain<br>Pavement preservation by adopting low-cost maintenance techniques is increasing among transportation agencies day by day. Chip seal, also known as seal coat, is widely used as a low-cost, thin surface treatment in preventive maintenance of asphalt pavements in many states, including Kansas. Loosening of aggregate particles from chip-sealed pavement and associated windshield damage to vehicles is a common problem. Thus the Kansas Department of Transportation (KDOT) uses lightweight aggregates as cover materials for chip seals. Although this has decreased windshield damage problems extensive chip loss on seal-coated pavements in the state has been reported. In this study, lightweight aggregates along with polymer-modified asphalt emulsion were used to determine proper aggregate and emulsion application rates to minimize chip loss in chip seals. Again, lightweight aggregates were studied in the laboratory to determine the effect of moisture content and electrical charge on chip loss. Evaluation of chip seal was performed by statistical analysis based on rutting potential, chip embedment, and retention. Results show that aggregate retention and embedment depth depend on aggregate-emulsion interaction, whereas rutting depends on the type of aggregate. Proper selection of aggregate and asphalt emulsion is important to maximize aggregate retention in chip seal. Chip loss also results from a lack of compatibility between the aggregate and asphalt emulsion. Results indicate that retention of aggregate depends on the prevailing charges of aggregate and emulsion particles. Moisture condition of the aggregate does not have any effect on chip loss. A new sweep test machine has been developed to assess chip loss, and it was found to be better than the sweep test currently recommended by the American Society for Testing and Materials (ASTM).
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Bethani, Sofia. "Production of lightweight aggregates from 'energy from waste' combustion ashes." Thesis, Imperial College London, 2004. http://hdl.handle.net/10044/1/7932.
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Metwally, Omar. "Characterization of fiber-reinforced lightweight concrete made of stalite aggregates." Master's thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/30665.
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Ce travail examine les propriétés mécaniques du béton léger (LWAC) fabriqué avec des granulats commercialement connus par Stalite et renforcé avec des fibres. Les paramètres étudiés comprenaient la résistance à la compression (25 et 40 MPa), le type de fibres (acier, synthétique, basalte-minibars ou BMB et hybrides) et la fraction volumique des fibres (0,5 et 1%). Les essais effectués comprenaient des essais de compression, de déformation axiale, de traction sous pression, de module d'élasticité, de flexion, de retrait et de perte de masse. De plus, des tests de pénétration des ions chlorure et de résistivité de surface ont été effectués pour examiner la durabilité du béton. Les résultats des essais ont montré que le coefficient d'efficacité du LWAC, défini comme le rapport entre la résistance à la compression et la densité, était supérieur de 16% à celui du béton de poids normal (NWC). De plus, le module d'élasticité de LWAC a chuté de 8,5 à 15,2% par rapport à celui de NWC alors que son coefficient de Poisson variait entre 0,2 et 0,24. L'ajout de fibres a amélioré les propriétés mécaniques du LWAC. L'absorption d'énergie de LWAC a augmenté de 129% en augmentant la fraction volumique des fibres BMB de 0,5 à 1%. De plus, le module de rupture du LWAC était plus élevé que celui prévu avec les formulations ACI 318 (2014). Les résultats des tests de durabilité ont montré que la pénétration des ions chlorure de LWAC était « très faible » selon la classification ASTM C1202 (2012). De plus, l'utilisation d'agrégats légers a augmenté la résistivité de surface du béton jusqu'à 150%. Cependant, l'ajout de fibres d'acier a augmenté la pénétration des ions chlorure et diminué la résistivité de surface du mélange, tandis que l'ajout de fibres BMB n'a montré aucune influence sur les deux paramètres.<br>This study investigates the mechanical properties and durability of lightweight aggregate concrete (LWAC) made with expanded slate coarse aggregates (commerciallyknown as Stalite aggregates) and reinforced with different types of fibers. The parameters investigated included the compressive strength (25 and 40 MPa), the type of fibers (steel, synthetic, and basalt-minibars or BMB, and hybrid fibers), and the volume fraction of the fibers used (0.5 and 1%). The experimental tests conducted to characterize the obtained LWAC included compression tests, axial deformation tests, pressure tension tests, modulus of elasticity tests, flexure tests, shrinkage tests, and mass-loss tests. Furthermore, both chloride-ion penetration and surface resistivity tests were carried out to examine the durability of LWAC mixes. Test results showed that the efficiency ratio of LWAC, defined as the ratio of compressive strength to density, was 16% higher than that of normal weight concrete (NWC). Moreover, the modulus of elasticity of LWAC dropped by 8.5 to 15.2% compared to that of NWC whereas its Poisson’s ratio ranged between 0.2 and 0.24. The addition of fibers significantly enhanced the mechanical properties of the LWAC. For instance, the energy absorption of LWAC increased by 129% by increasing the volume fraction of BMB fibers from 0.5 to 1%. Furthermore, the modulus of rupture of LWAC was higher than that predicted using ACI 318 (2014) formulations. In terms of durability, test results showed that the chloride penetration of LWAC was “very low” according to ASTM C1202 (2012) classification. Moreover, using lightweight aggregates increased the surface resistivity of concrete up to 150%. However, the addition of steel fibers increased the chloride penetration and decreased the surface resistivity of the mix while the addition of BMB fibers showed no influence on both parameters.
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Citeroni, Chiara. "Alkali-activated expanded lightweight aggregates for the production of special asphalt concretes." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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La presente tesi sperimentale si focalizza sulla produzione e successiva analisi, tramite test prescritti dalla normativa europea, di conglomerati bituminosi costituiti da aggregati leggeri che vadano a sostituire il 12% degli aggregati naturali, presenti in un tipico strato d’usura.
Questi aggregati leggeri sono stati originati partendo da due differenti polveri di scarto ad attivazione alcalina, quali polvere di basalto e bentonite esausta impiegati come principali precursori. Infatti, l’utilizzo di materiali di riciclo come prodotti sostenibili desta molto interesse nell’ambito ingegneristico, nello specifico in applicazioni su pavimentazioni stradali, in quanto essi possono rappresentare un modo per risparmiare energia e ridurre gli impatti ambientali.
Lo studio sperimentale si pone come ulteriore obiettivo la comparazione dei materiali leggeri sopracitati con l’argilla espansa, in modo da comprovare la loro efficacia e poterli considerare degli ottimi e più sostenibili sostituti.
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Vijayan, Vineesh. "Recycling alkali-activated powders for the production of lightweight aggregates for pavement applications." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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The objective of this thesis is to create an innovative approach to the development of flexible pavements with the use of synthetic aggregates for the production of porous layers. The synthetic aggregates are produced by the alkali-activation process. The potential application of artificial aggregates in the pavement, paves a way to reduce the use of natural materials to certain extends. This also helps to utilize the increasing growth of waste by-products generated from different kinds of industries. Furthermore, in this research the conventional Bitumen for asphalt concrete was substituted with a transparent binder. Hence this will hope to decrease the impact of carbon dioxide and carbon monoxide which are emitted from the production of traditional mixtures with Bitumen in the road industry.
The first part of experimental phase includes the recipe of making the geopolymer aggregates. The precursors concerned with this production are basalt powder and metakaolin. These powders are activated by the mixture of reagents such as Sodium hydroxide and Sodium Silicate. After discovering the optimum percentage of each precursors and solid-liquid ratio, the productions of synthetic lightweight aggregates start.
The next experimental phase involves the Mix design and characterization of a porous mixture. In this part, it has been decided to replace the natural white aggregates by 21% with the synthetic lightweight aggregates to form a semi-porous pavement design as per the European Standards. This design also replaces the traditional bitumen with a transparent binder named ‘EVIzero-28’ which is a synthetic binder used to produce eco-friendly asphalt. After the selection of mix design, the samples are produced to find out the optimum percentage of transparent binder content. Once it gets, then the samples are prepared for the further experimental phases like testing as per European Standards.
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Jahn, Jeroným. "Možnosti využití lehkého kameniva pro výrobu velmi lehkých betonů." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-371973.
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DIPLOMA THESIS IN THEIR THEORETICAL PART ARE FOCUSE , USE LIGHTWEIGHT AGGREGATES FOR THE PRODUCE OF VERY LIGHTWEIGHT CONCRETE, FOCUSES PRIMARILY ON FOAM GLASS AGGREGATES. THERE ARE ALSO MENTIONED OTHERS LIGHTWEIGHT AGREGATES, WHICH WE ARE USE FOR PRODUCE O VERY LIGHTWEIGHT CONCRETE. THEN THERE ARE RISKS UNITED WITH VERY LIGHTWEIGHT CONCRETE. IN THE PRACTICAL PART IS THE PROPERTY ANALLYSIS OF FOAM GLASS AGGREGATES, DESIGN RECIPE VERY LIGHTWEIGHT CONCRETE AND MONITORED MECHANICAL A THERMAL PROPERTIES OF THESE CONCRETE.
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Edwards, Derek Oswald. "An investigation into possible means of increasing the strength of lightweight high strength concrete." Thesis, [Hong Kong] : University of Hong Kong, 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1331161X.
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Belleggia, Marco Maria. "Synthesis and characterization of artificial aggregates and their potential applications in road construction." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016.
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L’obiettivo del progetto è stato quello di realizzare ed analizzare aggregati artificiali creati attraverso geopolimerizzazione e macro-incapsulazione di paraffina in aggregati leggeri espansi, discutendo i loro possibili impieghi nelle pavimentazioni stradali. Dopo un'accurata calibrazione delle miscele geopolimeriche, sono stati realizzati degli aggregati artificiali, in seguito caratterizzati in accordo con la norma UNI EN 10343, con l'intento di sostituire materiali stradali vergini. Contemporaneamente, sono stati prodotti aggregati leggeri impregnati di paraffina (PCM), in grado di cambiare fase una volta raggiunti all'incirca i 3 °C, e successivamente rivestiti da due strati di resina poliestere e
polvere di granito, denominati PLA: sfruttandone le proprietà termiche, si è valutato il loro possibile utilizzo come soluzione anti-icing. L’ultima fase della ricerca è stata incentrata nella realizzazione di aggregati geopolimerici espansi e molto porosi che potessero contenere una elevata quantità di PCM, sostituendo l'argilla espansa utilizzata nella produzione degli PLA.
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Awdel, Bengin Masiho. "Engineering properties of sustainable lightweight concrete incorporating novel aggregates produced by a novel technique of densifying waste polystyrene." Thesis, University of Wolverhampton, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637509.
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Kratochvíl, Jiří. "Alternativní kameniva na bázi druhotných surovin z energetického průmyslu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2014. http://www.nusl.cz/ntk/nusl-217094.
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The current usage of both classical and fluid combustion ashes is not sufficient and they are deposited in large quantities. The focus of this master´s thesis is to determine and verify some possibilities of their suitable applications in construction industry, specifically as the alternative aggregates for concrete. After the performed analysis several systems based on both classical and fluid combustion ashes have been proposed. Portland cement and hydrated lime were used as admixtures and binding properties of fluid combustion ashes were also tested. The most important properties were compressive strength and bulk density. The aim was to appropriate an optimal ratio between the addition of modifying substance and resulting strength of prepared aggregate in order to correspond to standards for aggregates for concrete.
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Marchi, Fabio. "Analisi termiche sull'impiego di materiali a cambiamento di fase (PCM) nelle pavimentazioni stradali." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016.
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Il presente lavoro di tesi mira a studiare l’utilizzo di aggregati artificiali (PLA) costituiti da aggregati leggeri (LWA) impregnati di materiali a cambiamento di fase (Phase-Change Materials, PCM) nei conglomerati bituminosi. L’obiettivo della tesi è quello di dimostrare che l’utilizzo di questi materiali nelle sovrastrutture stradali, grazie alla proprietà di cambiare fase (da solida a liquida e viceversa) in funzione della temperatura, induce una liberazione di calore. La conseguenza immediata dell’utilizzo di questi materiali è la ridotta necessità di manutenzione invernale, abbattendo i costi di ripristino della pavimentazione. Inoltre l’utilizzo di PLA non deve pregiudicare l’aspetto prestazionale e la vita utile dell’infrastruttura.
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Mohaine, Siyimane. "Etude des propriétés thermiques et mécaniques des bétons isolants structurels incorporant des cénosphères." Thesis, Ecole centrale de Nantes, 2018. http://www.theses.fr/2018ECDN0030/document.
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Dans le domaine de l’isolation thermique du bâtiment, les évolutions réglementaires (RT2012)et normatives (NF BPE : Béton à Propriétés Thermiques, septembre 2016) incitent à évoluer vers des bétons isolants et structurels (BIS). La maîtrise de leur conductivité thermique est primordiale. Il est possible, en plus de faire appel à un squelette granulaire léger, de jouer sur la nature de la pâte en utilisant des inclusions qui apporteraient un pouvoir isolant supplémentaire : les cénosphères. Dans un contexte de facilité de mise en oeuvre, à ces propriétés est rajouté le critère auto plaçant des bétons. On parle alors de Bétons Isolants Structurels Autoplaçants (BISAP). La maitrise et la validation de ces nouvelles formules dans le respect d’une approche prescriptive a nécessité la caractérisation des matériaux à différentes échelles (de l’inclusion à l’échelle de l’ouvrage) en développant des approches expérimentales et numériques. Leur comportement à l’état frais et à l’état durci a été analysé. Les conductivités thermiques mesurées placent ces nouveaux bétons dans la catégorie Bétons Isolants Structurels au sens du nouveau référentiel. Le modèle numérique développé permet d’approcher correctement les valeurs expérimentales. D’autre part, la sensibilité des BISAP incorporant des cénosphères à plusieurs indicateurs de durabilité (porosité accessible à l’eau, perméabilité,carbonatation et retrait) a également été étudiée. L’influence des microsphères est plus ou moins notable en fonction du mécanisme abordé<br>In the field of building thermal insulation, regulatory (RT2012) and standards (NF BPE: Béton à Propriétés Thermiques, September 2016) evolutions are encouraging the use of insulating structural concrete (BIS). The control of their thermal conductivity is essential. It is possible, in addition to using lightweight aggregates, to modify the composition of the cement paste by using hollow inclusions (fly ash cenospheres) to bring an additional thermal insulating potential. In a context of improved workability, to these properties is added the criterion of self-compacting concrete. The validation of these new formulas required the characterization of materials at different scales (from inclusion scale to building scale) by implementing experimental and numerical approaches. Their properties at fresh and hardened state were analyzed. The measured thermal conductivities place these new concretes in the Category of Structural Insulating Concrete in the sense of the new standard. The developed numerical model allowed approaching the experimental measurements correctly. The effect of cenospheres’ incorporation into cement paste on several durability indicators was also characterized
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Rossignolo, João Adriano. ""Concreto leve de alto desempenho modificado com SB para pré-fabricados esbeltos - dosagem, produção, propriedades e microestrutura"." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/88/88131/tde-25102005-104002/.
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Esta tese aborda a aplicação da tecnologia dos concretos leves de alto desempenho (CLAD) para a produção de elementos construtivos esbeltos pré-fabricados, tais como painéis estruturais e de vedação e peças para cobertura, apresentando um concreto com propriedades especiais em função da utilização conjunta de látex de estireno butadieno (SB), sílica ativa, superplastificante acelerador e agregados leves nacionais, denominado concreto leve de alto desempenho modificado com SB. Desenvolveu-se um amplo programa experimental para a análise dos concretos, tendo como objetivos o estudo dos processos de dosagem e produção, caracterização das propriedades dos concretos nos estados fresco e endurecido, análise da ductilidade de elementos construtivos esbeltos pré-fabricados submetidos à flexão, assim como a obtenção de informações microestruturais sobre a matriz de cimento e a zona de transição entre o agregado e a matriz de cimento. Os resultados do programa experimental demonstraram que os concretos leves de alto desempenho modificados com SB são extremamente adequados à produção de elementos pré-fabricados esbeltos, devido essencialmente à redução da massa específica e ao excelente desempenho das propriedades relacionadas à resistência mecânica e durabilidade. Nos estudos microestruturais, observou-se que a utilização de sílica ativa e de SB promoveram a diminuição da quantidade e do diâmetro dos poros capilares e da quantidade de hidróxido de cálcio (CH) na matriz de cimento, assim como reduziram a espessura da zona de transição agregado-matriz. Observou-se, também, que os concretos com agregados leves nacionais apresentaram valores da espessura da zona de transição agregado-matriz inferiores aos observados para os concretos com agregados tradicionais.<br>This dissertation deals with the application of the high performance lightweight aggregate concrete (HPLWAC) for the production of thin precast components, such as structural and insulation panels and elements for covering. A concrete with special properties was presented, once the use of styrene-butadiene latex (SBR), silica fume, accelerating superplastificizer and Brazilian lightweight aggregates, named SBR-modified high performance lightweight aggregate concrete. Our main goals in the experimental program were the study of concrete dosage and production, the characterization of concretes properties, the thin precast components analysis, as well as the microstructural study about both cement paste and the interfacial transition zone (ITZ) between aggregate and cement paste. The main results show that the SBR-modified HPLWAC are extremely appropriate to the production of thin precast components, due essentially to the density reduction and to the high performance of mechanical and durability properties. Besides this, it was viewed that the silica fume and SBR use promote the decrease of the amount and diameter of the capillary pores, as well as the amount of calcium hydroxide (CH) in the cement paste. Additionally, they reduce the thickness of the interfacial transition zone between aggregate and cement paste. It was also observed that the concretes with Brazilian lightweight aggregate presented lower values of the interfacial transition zone thickness than the ones observed for the concretes with traditional aggregates (basalt).
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Šenk, Josef. "Vývoj nového druhu lehčeného podlahového potěru se samonivelační funkcí." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227195.
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This thesis is focused on development of a new type of lightweight self-levelling floor screed. The aim of this thesis is to develop lightweight screed with self-levelling function, which could be stored in a dry mixture in bags or silos, designed for use with only addition of water.
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Morkusová, Kristýna. "Lehké malty s obsahem alternativních surovin odolné působení nepříznivých vlivů." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-371985.
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This diploma thesis describes research and following development of lightweight cement mortars with alternative raw materials. Attention was focused on study of the effects of extreme influences such as high temperature (up to 1200 °C), freeze-thaw and agressive sulfur dioxide. Verification of durability of developed mortars was realized using physical and mechanical tests (density and strength), physical and chemical methods (computed tomography) and scanning electron microscopy. Assessment of durability was realized in a longer period of time (90 days).
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Ghavam-Shahidy, Hamid. "Lightweight aggregate reinforced concrete deep beams." Thesis, University of Dundee, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.503556.
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Collins, Paul S. "Geotechnical properties of sand/lightweight aggregate mixtures." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ26989.pdf.
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Arasteh, A. R. "Structural applications of lightweight aggregate foamed concrete." Thesis, University of Westminster, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382269.
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Collins, Paul S. (Paul Steves) Carleton University Dissertation Engineering Civil and Environmental. "Geotechnical properties of sand/lightweight aggregate mixtures." Ottawa, 1997.
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Grotheer, Sarah Jo. "Evaluation of lightweight concrete mixtures for bridge deck and prestressed bridge girder applications." Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/768.
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Denno, Mohamad Ghyath. "The durability of high strength lightweight aggregate concrete." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336389.
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Asik, Mesut. "Structural Lightweight Concrete With Natural Perlite Aggregate And Perlite Powder." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607728/index.pdf.
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Structural lightweight aggregate concrete is an important and versatile material,
which offers a range of technical, economic and environmental-enhancing and
preserving advantages and is designed to become a dominant material in the new
millennium. For structural application of lightweight concrete, the density is often
more important than the strength. A decreased density for the same strength level
reduces the self-weight, foundation size and construction costs. Structural
lightweight aggregate concrete generally used to reduce dead weight of structure as
well as to reduce the risk of earthquake damages to a structure because the
earthquake forces that will influence the civil engineering structures are proportional
to the mass of those structures.
In this study, structural lightweight aggregate concrete was designed with the use of
natural perlite aggregate that will provide an advantage of reducing dead weight of
structure and to obtain a more economical structural lightweight concrete by the use
of perlite powder as a replacement of the cement. Six mixes were produced with
different cement content and with or without perlite powder. Six mixes divided into
two groups according to their cement content. First group had a cement content of
300 kg/m3 and second group had cement content of 500 kg/m3<br>also the water/cement
ratios of groups were 0.49 and 0.35 respectively. Moreover, each group had three
sub-mixes with 0%, 20% and 35% of perlite powder as cement replacement.
According to results of experimental study, it was concluded that natural perlite
aggregate can be used in the production of structural lightweight aggregate concrete.
Based on the strength and density results of experimental work, it is possible to
produce lightweight concrete with 20 MPa-40 MPa cylindrical compressive strength
by using natural perlite aggregate. Also, the use of perlite powder, which will
provide economy, can reduce dead weight further and increase performance.
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Li, Ming-Yan, and 李明彥. "Water absorption characteristic of lightweight aggregates and its effect on the properties of lightweight aggregate concrete." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/47989902734599604715.
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Ho, Cheng-Han, and 何政翰. "Durability of Reinforced Lightweight Concrete Subject to Different Lightweight Aggregates." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/96938024590391477228.
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碩士<br>朝陽科技大學<br>營建工程系碩士班<br>97<br>In this research, the durability of reinforced lightweight concrete subject to different lightweight aggregates is investigated. Four mix design concretes included ordinary concrete, two lightweight aggregate concretes and pervious lightweight aggregate concrete. The project aims to run the steel corrosion test for the reinforced lightweight aggregate concrete in sea water dry-wet immersion and carbonization tests. The study will be tested and evaluated by the following items: compression strength, bending strength, splitting tensile strength, carbonated depth measurement, corrosion potential method, water absorption, optics microscopy examination.
The findings showed that the higher specific weight of lightweight aggregate concrete exhibit relatively high strength and unit weight. In the same water-cement ratio level, the strength of higher density of lightweight aggregate concrete would reach those of normal concrete.
At the accelerated carbonation test, the carbonation depth of concrete would increase with time and there is a gradual increase in carbonation depth trend. The carbonation depth of lightweight aggregate concrete specimens was the almost same as compared with those of normal concrete ones after 240 hours accelerated carbonation test. In dry-wet immersion by sea water test, reinforcement corrosion potential values were less than-350mV CSE after 20 cycles, the corrosion probability is higher than 90%. After 20 drying and wetting cycles of sea water immersion test, the cracking of concrete specimens does not appear.
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Chiu, Ching-Liang, and 邱敬量. "Lightweight Aggregates Produced by River Sediment." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/3nwhsx.
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碩士<br>國立中興大學<br>土木工程學系所<br>106<br>It is getting more difficult to find the place for the storage of river dredging sludge in Taiwan. Recycling might be an alternative method to close out the fluvial sludge, which not only solves the problem of sludge storage but decreases the probabilities of environmental pollution caused by the distribution of fluvial sludge. In this study, we aimed to evaluate the feasibility for the production of lightweight aggregates using the fluvial sludge collected from the downstream of the Wu River in Taichung, Taiwan. Such information could serve as the scientific evidence for the government to achieve the sustainable development of natural environment. The literature review was firstly conducted to compare the chemical composition and production condition of lightweight aggregate. The collected information was used to determine the feasibility for the production of lightweight aggregates using the fluvial sludge in the Wu River.
According to the results of chemical analysis, the fluvial sludge in the Wu River consists of 60% of SiO2, 14% of Al2O3, 16.5% of Fe2O3, 5% of CaO + MgO, and 2.3% of K2O + Na2O. With the exception for the high proportion of Fe2O3, other elemental composition suggested that the fluvial sludge in the Wu River is an appropriate material for the production of lightweight aggregates. Compared with the fluvial sludge in the Yangtze River in China, the relative high proportion of Fe2O3 in the Wu River sludge results in an excellent expansion property. In addition, the particle size of the Wu River sludge ranges from 10 μm to 50 μm, which resulted in a superior ductility for the material. Collectively, the fluvial sludge collected from the downstream of the Wu River is a promising material for the production of lightweight aggregate.
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Chen, Chao-An, and 陳昭安. "Lightweight Aggregates Produced by Textile Sludge." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/naphzv.
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碩士<br>國立中興大學<br>土木工程學系所<br>106<br>The large waste sludge output has caused a great deal of troubles in the country. Due to the rising awareness of domestic environmental protection, a lot of disposal methods have not been accepted by the public, such as incineration or landfill. Because the incineration furnace energy consumption and pollution, as well as the volume of landfill are difficult to find, are caused by a considerable burden on society.The studies of sludge recycle at home and abroad have been considerable and are seen in the literature, but there is still a long way from the actual application. How to find a new pipeline to re-use, reduce the waste sludge in human life has been an important research topic for governments around the world.
In this experiment, reservoir clay mix with textile sludge as sintered material of lightweight aggregate and tried different temperatures of the preheating temperature, sintered temperature and holding time to evaluate textile sludge sintering lightweight aggregate.The particle density of textile lightweight aggregate (adding 20% textile sludge) ranged from 0.97 to 1.82 g/cm3, and the water absorption ranged from 19% to 37%. When reservoir sludge is added with textile sludge to sinter light aggregate, the particle density shows a downward trend while the water absorption shows an upward trend. The sintering results show that in most conditions the lightweight aggregate has particle densities between 1.1 g/cm3 and 1.8 g/cm3, so the lightweight aggregate with added textile sludge has a particle density that can be used for the structure.In addition, according to the experimental data, as the sintering temperature increases, the water absorption shows a downward trend, so infer 400 ℃ preheated and 1200 ℃ sintering may be more suitable for the conditions of textile lightweight aggregate. Moreover, to reduce the water absorption can try a higher sintering temperature, and the increase in preheating time did not significantly reduce the water absorption.
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Chen, How Ji, and 陳豪吉. "Lightweight concrete production using the lightweight aggregates in Taiwan and its strength characteristics." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/17645401964458677237.
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Yen-Po, Lai, and 賴彥博. "Enhanced conversion of sediment/sludge to lightweight aggregates." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/53589498681657756556.
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碩士<br>東海大學<br>環境科學與工程學系<br>102<br>This study used harbor sediment, reservoir sediment and drinking-water treatment sludge to sinter lightweight aggregates. Study of the lightweight aggregate bloating and sintering was performed via two different granulation methods (3000 psi and atmosphere pressure). The results show that the structure is looser for the products granulated under atmosphere pressure. At high temperature, the gases easily dissipated to the outside of the sample. And sintered at 1200℃, most samples have a water absorption less than 12 % that meets industrial practical requirements. X-ray absorption results suggested that iron in HL and FY sediments is mainly Fe3+ that leads to a poor flux and makes sintering and foaming difficult. This study found in 2-3 minutes, bloating starts. And heating for 10 minutes produced the largest volume for the samples. So the sintering for producing lightweight aggregates can be shortened to 10 minutes. It will reduce the cost of sintering for lightweight aggregates and achieve carbon reduction.
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Wang, Shun-Yuan, and 王順元. "The application of recycled waste for producing lightweight aggregates." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/04641041754466232613.
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博士<br>國立中興大學<br>土木工程學系所<br>98<br>Due to the fact that lack of natural resources and waste disposal sites has gradually become rare in Taiwan, the recycling of coal-fired power plant''s bottom ash, reservoir sediment and incineration fly ash, not only is transformed into a resource but can also reduce the load of the domestic environment. Therefore, this research is based on these three categories of wastes to carry out the experiments for developing lightweight aggregates. On the one hand, it is able to establish and access to the production technology of energy-saving and environmentally friendly lightweight aggregates, on the other hand it also can help the government to deal with the three types of waste disposal and recycling. The ultimate goal is to provide this research results of environmentally friendly new materials for industrial waste control center to take into account, which is expecting to implement the policy objectives of sustainable resources.
The results of the study on the lightweight aggregates sintered by the coal bottom ash showed that, the coal bottom ash could be used as the raw material for sintering lightweight aggregates. The type of sintered coal bottom ash lightweight aggregates were produced with the loose unit weight of between 900-1100 kg/m3; the crushing strength of greater than 4 MPa. The type of expanded coal bottom ash lightweight aggregates had the loose unit weight of about 500 kg/m3; the crushing strength of greater than 3.5 MPa. Moreover, the sintered bottom ash lightweight aggregates produced by Lin-Kou power plant''s bottom ash with the coal strength mark of 50 MPa were considerably suitable for the aggregates used in the structural lightweight concrete. By means of the heat treatment processes, the chlorine ion content in the coal bottom ashes could be effectively reduced, so that the lightweight aggregates satisfied the demand for general construction.
The results of the study on the lightweight aggregates sintered by the incineration fly ash showed that, incineration fly ash should be used as admixtures for sintering lightweight aggregates, and the suitable adding amount should not exceed 30%. The various properties of lightweight aggregates produced by the rotary kiln trail were as follows: The particle density was about 1.0 g/cm3; the loose unit weight was 593 kg/m3; the crushing strength was 6 MPa; the strength mark was 25 MPa, i.e., the reasonable strength of resulting concrete was greater than 25 MPa; the heavy metal leaching tests conformed to "the Toxicity Characteristic Leaching Procedure (TCLP) of Industry Wastes" prescribed by the Environmental Protection Administration (EPA).
The results of the study on the lightweight aggregates produced by the reservoir sediment showed that, the reservoir sediment was very appropriate for used as the main material for the production of lightweight aggregates. The Shih-Men reservoir sediment lightweight aggregates were successfully produced by using the rotary kiln. The physical properties of the reservoir sediment lightweight aggregates form 15 sites evaluated in the laboratory were within the proper range of making artificial lightweight aggregates. It meant that the reservoir sediment could be used as the raw material of lightweight aggregates. The particle density was in the range of 0.6-2.0 g/cm3; the 24-hr water absorption was about 0.2-14%; the strength mark was 40 MPa, i.e., the reasonable strength of resulting concrete was greater than 40 MPa.
The results of the study on the expansion mechanism of the reservoir sediment lightweight aggregates showed that, the visco-plastic melts were composed of both the melting quartz and silicate (2FeO．SiO2); the expansion gases mainly included 4 kinds of gases, e.g., carbon monoxide, water, oxygen, carbon dioxide, which should originate from the heat actions on the sediment’s compound compositions, e.g., organisms, carbonates, ferric oxides, mineral crystal water. Besides, through verifying the trial results, it could be known that the formation of expansion gases were primarily dominated by the reductions of organisms and ferric oxides. The temperature and time used in course of production processes had a great effect on the physical properties of sediment lightweight aggregates. For pre-heating, the lower the temperature and the shorter the time used, the more the gases could be formed as well as the higher relative particle density and volume expansion ratio of aggregates; in contrast, the higher the temperature and the longer the time used, the denser the glass shell of particles, which could substantially reduce the permeation of water molecules.
The results of the study on the high performance lightweight aggregates produced by reservoir sediment showed that, on the basis of the specific designed production conditions and adding little amounts of additives, the lightweight aggregates with excellent performance were successfully produced, e.g., the particle density of 1.1 g/cm3; 24-hr water absorption of lower than 3%; vacuum water absorption of lower than 5%. By the observation on the scanning electron microscope (SEM), the pore structure of aggregates was the same as that of the commercially-available high performance lightweight aggregates, e.g., the independent and closed spherical pores, the uniformly distributed and cellular network structures, the pore size of approximately about 2-50 μm. In addition, the low temperature and long period of heating as well as the extra-fined raw materials were the critical factors to produce high performance reservoir sediment lightweight aggregates.
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Xiao, Bo-Yang, and 蕭博仰. "Forming Gases of Reservoir Sediments Lightweight Aggregates under Sintering." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/14256913244246481113.
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碩士<br>中興大學<br>土木工程學系所<br>94<br>This study aims to investigate the generation of evolving gases of the reservoir sediment lightweight aggregates (RSLA) during sintering in Taiwan. The test programs are conducted primarily on the thermal-analyzer coupling mass spectrometer (TA-MS) to differentiate varieties of evolving gases generated during the swelling of RSLA with continuous heating under high temperature. In which, three kinds of reservoir sediments (Shihmen, Wushe, and Minghu reservoir) are used as raw materials and the shales (Hualien) are regarded as a control. Further, cooperated to the experimental results of lightweight aggregates sintered by the furnace, the formation mechanism of the evolving gases generating from the expansion of RSLA can be generalized synthetically.
The experimental results show that, the principal types of the evolving gases cause the expansion of RSLA including carbon monoxide, hydrosphere, oxygen and carbon dioxide. These gases are mainly derived from the components of reservoir sediments (including the organic matter, ferric oxide and mineral hydrosphere, etc.) as heated. Moreover, based on the experimental results of lightweight aggregates sintered by the furnace, it also verifies that the critical factor of the gases formation resulting in RSLA expansion is the redox reactions between carbon and ferric oxide. Consequently, the physical properties of the RSLA could be improved by the adjustments in carbon and ferric oxide content.
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Ho, Kuo-Yi, and 何國意. "Water Absorption Characteristic of Lightweight Aggregates and its Effect on the Thermal and Mechanical Properties of Lightweight Aggregate Concrete at Elevated Temperatures." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/43787628614886921697.
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碩士<br>國立中興大學<br>土木工程學系所<br>100<br>The research discuss the water absorption characteristic of lightweight aggregates and its effect on the thermal and mechanical properties of lightweight aggregate concrete.
The contexts of the research are separated by two parts. The first part is the basic property tests of the concrete material, including compressive strength, flexural strength, splitting strength, elastic modulus and thermal conductivity. The second part is the to load bearing behavior, fire resistance and heat insulation tests of reinforced concrete beams members and slab members. The experiment variables include pre-wetted time of lightweight aggregates (oven dry, 30 min) and the maximum elevated temperatures (400℃, 600℃, and 800℃).
For the property of the concrete material, the experimental results showed that the thermal conductivity of normal concrete is higher than lightweight aggregate concretes at elevated temperature. The main reason is because the multiple pore structure in the lightweight aggregate concretes reduces the thermal conductivity. While at the higher pre-wetted time, the thermal conductivity of the lightweight aggregate concretes slightly reduced due to the lower density. The splitting strength and flexural strength of the lightweight aggregate concretes experimental results showed that, the splitting strength and flexural strength slightly increased at lower than the 400℃ maximum elevated temperature. It is because the water inside the concrete and the cement with un-completely hydrate role were heated by increasing temperature so that the inside water complete role with concrete and promote the flexural strength.
For the tests of reinforced concrete beams members and slab members, the experimental results showed that, variations in mechanical and thermal properties due to the elevated temperatures for lightweight aggregate concretes with different pre-wetted time were all smaller the those for normal concrete if the spalling of concrete did not occur. However, there were higher chances to spalling when we choose lightweight aggregates with oven dry. Furthermore, there were no difference of to load bearing behavior at elevated temperature between the pre-wetted time of lightweight aggregates and reinforced concrete beams members and slab members.
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WONG, SHAO-DI, and 翁少笛. "Preparation of Lightweight Aggregates Using a Salt as Flux Promoter." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/89168327127513220807.
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Cheng, Shao Hsiang, and 鄭少翔. "Preparation of lightweight aggregates withcoal fly ash and glass wastes." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/38754159908919462139.
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碩士<br>東海大學<br>環境科學與工程學系<br>101<br>This study digests coal fly ashes with microwave-assisted digestion under various temperatures. The compositions of coal fly ash are determined by ICP-AES. The results show that microwave digestion can improve significantly the analytical outcome. And Al, Ca, and Fe contents obtained increase when increasing temperature.
This study also uses fly ash mixed with waste glass to make lightweight aggregate. The mixed wastes are formed into pellets with a pressure of 3000psi. They are fired for certain time at high temperatures, and removed from the furnace to cool. Physical and chemical properties of the aggregates are determined to compare the effect of added waste glass on firing coal fly ashes into lightweight aggregates.
This study further adds flux of carbonates, sulfates, chloride salts to the mixtures to reduce sintering temperatures. Physical and chemical properties of the aggregates are determined to compare the effect of added salts on firing mixtures of coal fly ashes and waste glass into lightweight aggregates.
The results show that except the aggregate made from pure coal fly ash fired at 1050oC, all the aggregates are in compliance with specifications of lightweight aggregate’s particle density <2 g cm-3. Addition of waste glass and flux salts can reduce the required temperature for sintering coal fly ash into lightweight aggregates. Flux salts either decompose or volatilize at high temperatures to produce gases that expand aggregates.
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Chen, Chien-Kuo, and 陳建國. "The Research on Critical Impacts of Insulation Performance of Lightweight Concrete：The Case Study of Three Lightweight Aggregates." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/p86m9k.
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碩士<br>中國科技大學<br>建築研究所<br>102<br>Due to the high housing density in urban areas as well as the uncertain insulation performance of traditional aggregate concrete, more and more air-conditioned devices are equipped to take control of the temperature in the rooms. As a result, the issue of energy waste appears. In order to solve the problem of energy consumption, raising the quality of better insulation performance to gain the effective use of energy has become an important topic at the present times.
Compared with traditional aggregate concrete, lightweight aggregate concrete keeps the characteristics of lighter weight and lower thermal conductivity. When lightweight aggregate is applied to construction, the weaknesses of heavy weight and poor insulation performance of traditional aggregate concrete can be improved. This research is aimed to investigate the key factors of insulation performance in three different kinds of lightweight aggregates：Ceramsite、Vermiculite、Perlite. Through the analysis of water absorption rate, thermal conductivity quotient and compressive resistance on three experimental objects whose proportion of lightweight aggregates to concrete were 1:6, 1:7 and 1:8, the experiment results not only provide suitable references to architecture designers but also offer appropriate proportion of lightweight aggregate concrete to make insulation performance better while construction work is progressing.
According to the experimental results on physical properties, ceramic aggregate performs better than the other two aggregates in term of water absorption rate, compressive resistance and thermal conductivity quotient (K). In details, ceramic aggregate concrete in the proportion of 1:7 performs the best in the aspects of water absorption rate and compressive resistance. Ceramic aggregate concrete in the proportion of 1:6 performs the best in the aspects of thermal conductivity quotient (K).
By analyzing the insulation performance of the three lightweight concrete stated above, perlite aggregate shows better insulation performance. The mean temperature difference (MTD) in a perlite aggregate box reaches the biggest, 1.66℃. The MTD in a vermiculite aggregate box reaches the second, 0.96℃. The MTD in a ceramic aggregate is the smallest, 0.38℃. As a result, the use of perlite aggregate concrete is able to create better insulation performance.
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Chen, Zhi-Ming, and 陳致銘. "Engineering properties of hollow sphere lightweight aggregates manufactured from reservoir sludge." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/85454914636501816620.
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碩士<br>國立成功大學<br>土木工程學系碩博士班<br>95<br>With the rapid increase of reservoir sludge in Taiwan, some adequate and economical methods proposed for the disposal of reservoir sludge are urgent and necessary. Traditionally, reservoir sludge is utilized to produce lightweight aggregates used as construction materials in civil engineering. However, the shape and porosity of this kind of lightweight aggregates are difficult to control, resulting in a variation of their quality. In this study, we attempt to improve the physical and mechanical properties of lightweight aggregated by making a series of hollow spheres with different densities from reservoir sludge.
At first, the physical and mechanical properties of reservoir sludge evacuated from Wu-San-Tou reservoir after suffering from various high temperatures were measured and then compared to each other. Secondly, hollow spheres manufactured from the reservoir sludge after suffering from different high temperatures were produced and tested. As a result, methods for making hollow spheres with sufficient strength and lower density were proposed. Finally, the physical and mechanical properties of hollow spheres with sufficient strength and lower density were measured and discussed.
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Chang, Sheng-Nan, and 張勝南. "Producing Lightweight Aggregates by Incorporating Tile Grinding Sludge with Reservoir Sediments." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/4ry88u.
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博士<br>國立中興大學<br>土木工程學系所<br>106<br>The main purpose of this study is to examine the feasibility of making lightweight aggregates (LWAs) with reservoir sediments or sludge, water purification (WP) sludge generated in water purification facilities (WPFs) and grinding sludge from brick making. Sludge was collected from reservoirs and WPFs in Taiwan for physical properties testing and chemical composition analysis. Then, the two types of sludge were included together with grinding sludge for firing tests in the lab for making of LWAs. The finished LWAs were tested for their physical and engineering properties.
Results show that WP sludge meets the requirements as a raw material of LWAs despite having larger particle diameters with a maximum up to 0.014 mm in wet periods due to higher raw water turbidity compared to dry periods. With a specific gravity in the range of 2.63 to 2.73 and in the form of silt or clay sediments, it is a suitable raw material for making of LWAs. With its chemical contents all falling within the appropriate ranges recommended by literature, it should be able to form LWAs.
Taguchi methods were also applied to combine grinding sludge from brick making with reservoir sediments for making of LWAs. For this, an orthogonal array was employed, which included five controllable four-level factors (i.e. sludge content, preheating temperature and time, sintering temperature and time). Analysis of variance was performed to investigate how these experimental factors affected the finished LAWs in terms of particle density, water absorption, expansion ratio and loss on ignition. Overall, the finished LAWs have particle density in the range of 0.43 to 2.1 g/cm3 and water absorption in the range of 0.6 to 13.4%. These values are comparable with requirements for general and high performance LAWs. These results indicate that it is relatively feasible to make high performance LWAs with the combination of grinding sludge from brick making and reservoir sediments.
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Wu, Te-Tsan, and 吳德燦. "The Application Lightweight Aggregates of Reservoir Sediment Used in Manufacturing Permeable Bricks." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/5s9rry.
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碩士<br>國立臺北科技大學<br>土木與防災研究所<br>102<br>The technology of producing lightweight aggregate from reservoir sludge has been developed for years in Taiwan. Many manufacturers have invested in mass production of lightweight aggregate with various properties such as heat insulation, sound insulation, fire resistance, etc. Such material has been used in construction engineering and meets green building standards. Traditional sand and gravel aggregates can be replaced with lightweight aggregates to mix lightweight concrete and it was successfully used for the bridge construction on national rout 6. The Ministry of Transportation and Public Constructions Committee continue to promote the use of lightweight aggregate in public constructions. The lightweight aggregate produced by using reservoir sludge, due to its porous characteristic, when used to manufacture lightweight permeable bricks, are suitable for use in landscape or outdoor pavement, such as square, sidewalk, landscape trails and bike paths, etc. It can also be used at riverside and slope protection for disaster prevention purposes. The lightweight aggregate achieves waste recycling and ecological environmental protection goals. In addition to the efficient resource utilization of reservoir sludge, the lightweight aggregate meets the concept of green environmental protection.
In this study, the lightweight aggregate manufactured using Shimen Reservoir sludge was sieved and classified according to particle size into three groups: coarse (1/2″to 3/8″), medium (3/8″to 1/4″) and fine (1/4″~ # 8). Water-permeable bricks were made using each group of lightweight aggregate under the condition of fixed amount of cement (360kg/m3) and water-cement ratio to investigate the relationship between coefficient of permeability and compressive strength of lightweight aggregate of coarse, medium and fine particle sizes. The permeable bricks produced in this study weigh about 1300~1600kg/m3 having coefficient of permeability of 10~100×10-2cm/sec and compressive strength of 220~320kgf/cm2. With the same amount of cement, water-cement ratio and vibration condition, the comparison result of the coefficient of permeability was coarse > medium > fine group. The result of the compressive strength was medium > coarse > fine group. The result of coefficient of permeability corresponds to the size of void of the particle size from large to small while the result of compressive strength is greater for medium particle size. This is because medium size particles are wrapped more completely and evenly in cement paste and the paste linkage between particles is more complete and thus fully giving the strength of cement paste.
Further, the three groups of materials were mixed and compared. The results revealed that the compressive strength of the bricks made of mixed material is only slightly greater than the bricks of coarse particles and less than the bricks of medium particles while the permeability of the bricks made of mixed material is in between of the bricks of medium particles and those of fine particles.
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林志喬. "The Fundamental Atudy Of Lightweight Aggregates Derived From CIGS Thin Film Aolar Cells." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/utucc3.
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碩士<br>大漢技術學院<br>土木工程與環境資源管理研究所<br>105<br>In this study, the waste film CIGS thin film solar cell glass as preparing a lightweight aggregate material, related research shows that sintering waste glass of preparing a lightweight aggregate at a temperature of more than 1000 ℃. This study attempts to H3BO3 and Na2CO3 as flux below 1000 ℃ sintered lightweight aggregate formation, and test the water absorption of aggregate, depending on the porosity, bulk density, compressive strength, health and toxicity dissolution test (TCLP) and other properties. Since H3BO3 and Na2CO3 can promote the gas phase and the viscous glass coated internally generated waste glass powder formed in the low temperature formation of lightweight aggregate, but the viscous glass phase barrier to oxygen diffusion into the interior of the test may cause binder during sintering is not completely burned to produce aggregate so sinister phenomenon, according to the experimental results show that, under the premise of maintaining the molding result dose reduction PVA binder can help reduce or eliminate the sinister phenomenon.
Research is divided in two flux for preparing a lightweight aggregate respectively as boric acid and sodium carbonate as a flux, preparation of porous lightweight aggregate in a different amount of additives, sintering temperature and time, when the dose amount of borate fluxes reach more than 10% lightweight aggregate nature at 700℃ baking 1 hour generated as follows:
(bulk density (g / cm3): 1.464, water absorption (%): 0.089, depending on the porosity (%): 0.130, sexual health (%): 0.063, compressive strength (kgf / cm2): 820.045.
In addition, when the amount of sodium carbonate added dose of flux reach more than 17.5%, fired for 1.5 hours at 810 ℃ arising lightweight aggregate characteristics are as follows: (bulk density (g / cm3): 1.380, water absorption (%): 0.739, depending on the porosity (%): 1.016, sexual health (%)::0.069, Compressive strength (kgf / cm2) : 383.153).
And through the scanning electron microscope image analysis can be learned within the hole with the distribution of bone, it was confirmed that the four properties of bulk density, apparent porosity, soundness and water absorption were in accordance with the requirements of CNS-3691, in addition the compressive strength is also in line with CNS-3036 specification, displayed CIGS solar thin-film battery glass by low-temperature co-firing technology, at 1000℃ below firing high compression and low water absorption, low-density lightweight aggregate.
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Mechleb, Ghadi. "The effect of expanded shale lightweight aggregates on the hydraulic drainage properties of clays." 2013. http://hdl.handle.net/2152/21933.
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Fine grained soils, in particular clays of high plasticity, are known to have very low values of hydraulic conductivity. This low permeability causes several problems related to vegetation growth and stormwater runoff. One way to improve the permeability of clay soils is by using coarse aggregates as a fill material. Recently, Expanded Shale has been widely applied as an amendment to improve drainage properties of clayey soils. However, limited effort has been made to quantify the effect of Expanded Shale on the hydraulic conductivity or on the volume change of fine grained soils. Specifically, the field and laboratory tests required to quantify the amounts of Expanded Shale to be mixed with clays to obtain desired hydraulic conductivity values have not been conducted.
This paper presents the results of a series of laboratory fixed-wall permeameter tests conducted on naturally occurring clay deposits in the Austin area with different plasticity. The testing program comprised of clay samples with different quantities of Expanded Shale aggregates by volume, ranging between 0 and 50%, and compacted at two different compaction efforts (60% and 100% of the standard Proctor compaction effort).
The laboratory test results indicate that the hydraulic conductivity of the three soils increases by at least an order of magnitude when the Expanded Shale is mixed in quantities between 25 to 30% by volume depending on the compaction effort. Expanded Shale amended samples also showed lower swelling potential with increasing amendment quantities. Moreover, when the clay with the higher plasticity was mixed with 25% Expanded Shale, the compression and recompression ratios decreased by 25% and 15% respectively.<br>text
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Yen-MingDong and 董彥明. "The Influence of Bloating Additives on the Preparation of Lightweight Aggregates using Reservoir Sediments." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/37491576372611235942.
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碩士<br>國立成功大學<br>資源工程學系碩博士班<br>98<br>The concrete made from lightweight aggregates has the advantages of building light self-weight, good thermal and acoustic insulations. The sediments dredged out from reservoir have become one of the raw materials to manufacture lightweight aggregates. The discovery of reservoir sediments being able to sinter into lightweight aggregates not only solves the environmental impact caused by the sediments deposition but also substitutes some of the natural aggregates. Therefore, reservoir sediments have become a source manufacturing highly-valued green construction material.
Many recent researches have reported that reservoir sediments have the potential of manufacturing lightweight aggregates, however, there are still some improvements can be pursued such as bulk density, water absorption and compressive strength. This study investigated the effects and conditions of adding bloating materials into the sediments, expected by followed sintering to obtain aggregates with better qualities in density, water absorption and compressive strength than that from sediments only. Furthermore, the conditions to obtain ultra-lightweight aggregates with large and uniform pores to be used as acoustic insulation and fire-proof materials were examined.
The reservoir sediments used in this study were collected from Shihmen Reservoir in Tao-Yuan County. The sediments were mixed with different percentages (2.5%, 5%, 7.5% and 10%) and sizes (100/200 mesh, 200/400 mesh, ＜400 mesh and ＜5μm) of dolomite or marble powders as bloating additives. The influences of these additives were investigated. Based on the experimental results, the following conclusions can be drawn:
1. The median size (d50) of reservoir sediments is 3.8μm. The mineral compositions of sediments are mainly quartz, illite and chlorite. Chemical composition is located in the bloating region of Riley phase diagram.
2. Using only the reservoir sediments as the raw material, a viscous glassy material can be generated and to seclude the gas and dilate at 1150℃. Sintered at 1250℃, the bulk density of the aggregates is around 1.48 g/cm3 .
3. For sediments mixed with 5%, ＜400 mesh dolomite and sintered at 1175℃, the bulk density of the aggregates produced can be reduced to 1.46 g/cm3, showing that the addition of bloating materials can help to reduce the sintering temperature. Sintered at 1250℃, the density can further be reduced to 0.93g/cm3, proving that bloating materials can help to reduce the density of the aggregates. When dolomite addition is increased to 7.5%, the fluxing effects due to the calcium and magnesium content made the aggregates to collapse at 1200℃. Therefore bloating materials addition ratio and sintering temperature should be properly adjusted.
4. The amount and connectivity of open pores in the aggregates are related to the particle size of the additives. Bloating materials with sizes ＞200 mesh can produce connected open pores allowing gas to escape, and deteriorating the dilation of the aggregates. The density is similar to the density of aggregates made from only sediments. Additives with sizes ＜400 mesh can reduce the connectivity of pores and seclude the gas efficiently, it is even able to manufacture aggregates with bulk density less than 1 g/cm3.
5. The adding of bloating additives increases the aggregate porosity and the density, however, it also let the compressive strength decrease. The aggregates prepared in this study have average densities in the range of 1.8 ~ 1.2 g/cm3, and the compressive strengths are between 49.97 and 10.72MPa, which fulfill the requirements in lightweight concrete preparation.
6. The optimum conditions for lightweight aggregates in this study are as follows: 200/400 mesh dolomite 7.5%; sintering at 1200℃ for 30 min. The lightweight aggregates produced have the properties: density 1.23 g/cm3; water absorption less than 1% and compressive strength 19.1MPa. This is suitable for the application in structural concrete.
7. Addition of 5%, ＜5μm dolomite as bloating materials and sintered at of 1250℃, the aggregates produced can have densities as low as 0.63 g/cm3. The ultra-light aggregates with large and uniform pores, are suitable in the application of heat and acoustic insulation purposes.
8. The bloating mechanism and ability of marble powders in the manufacture of lightweight aggregates are similar to dolomite, and occasionally even better.
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黃素珍. "Recycling of quarries, contaminated soils and incinerator fly ashes in production of lightweight aggregates." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/02436146017684601875.
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Fu, Chien-chang, and 傅建璋. "The Influence of Heating Rate on the Preparation of Lightweight Aggregates using Shihmen Reservoir Sediments." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/37913254387509315345.
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碩士<br>國立成功大學<br>資源工程學系碩博士班<br>97<br>Due to geological condition and improper exploitation, the reservoirs in Taiwan have serious sediments problems, which shorten the life of reservoirs. In Taiwan Province, there are 46 reservoirs, which have detailed sedimentation survey. The total sedimentation amounts are estimated about 18%. Among the reservoirs, in eastern Taiwan, the sedimentations are the lowest, not more than 1%. While in the western, in north, center and south location, half of them sedimentations are over 30%. The situations are quite serious. The Shihmen Reservoir is located in the mid-stream of Tahan River. It is in the administrations of Daxi, Lungtan and Fuxing Townships of Taoyuan County, and of Guanxi Township of Hsinchu County. The area of reservoir watershed is 763.4 square km2 and total capacity is 309,000×103 m3. Its current effective total capacity is approximately 208,976.0×103 m3 and the sedimentation is 32.37%. In order to increase lifetime of reservoirs as well as to increase their capacity, sediments cleansing is a task not to be delayed. The disposal of reservoir sediments includes two major works, one is the removal of sediments, the other is its transformation to useful resources.
Sediments taken from Shihmen Reservoir were tested in this study. The analysis showed that the chemical composition was located in the bloating region of Riley diagram, suggesting its feasibility for lightweight aggregates manufacturing. Reservoir sediments were prepared at different conditions, the results show: raising sintering temperature increases the amount and size of closed pores, as well as the connectivity among the pores. The density and compressive strength decrease as sintering temperature is lengthen. The Bulk density and compressive strength decrease as sintering duration is lengthen, while the apparent density increases for above vitrification temperatures (ca. 1200˚C~1250˚C). The heating rate does not significantly influence the density of the aggregates. Compressive strength increases as the heating rate is increased, however the extent is minor.
The optimal conditions of preparing lightweight aggregates are: heating rate 5~15˚C/min, sintering temperature 1200˚C~1250˚C, duration 30 minutes. The properties of aggregates prepared are: bulk density 1.45~1.77 g/cm3; water absorbing less than 1%; compressive strength 30.07~20.80 MPa. The aggregates can be used for manufacturing lightweight concrete for structural application in civil engineering. Lightweight aggregates prepared at 1300˚C can be used for manufacturing lightweight concrete for insulation prepares.
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Winter, Adrian Jeremy. "An assessment of the effect of grading of perlite on ultimate strength in lightweight concrete." Thesis, 1998. https://hdl.handle.net/10539/26448.
Full textAbstract:
A RESEARCH REPORT SUBMITIED TO THE FACULTY OF ARCHITECTURE.
UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG, FOR THE DEGREE
OF MASTER OF SCIENCE IN BUILDING<br>This research project is an investigation into the effect of the grading of perlite
lightweight aggregates on the resultant concrete strengths.
Lightweight concretes are reviewed.
Perlite, as a lightweight aggregate, is assessed.
Grading theory for aggregates and in particular lightweight aggregate is analysed.
A series of mix designs are proposed with manipulation of the grading of the perlite as
the only variable. This is so that variations in compressive strength and density may
be assessed in terms of the grading of the perlite.
Those mixes are undertaken and tested for compressive strength and dry density.
In this research project compressive strength is considered a benefit, while mass is
considered a disadvantage.
The performance of a lightweight concrete is assessed firstly in terms of the Power
Factor. The Power Factor is the compressive strength divided by the dry density of a
concrete.
The performance of lightweight concretes produced with Perlite aggregate is assessed
secondly in terms of the Cement Content factor. The Cement Content Factor is the
Power Factor divided by the Cement Content. This factor has the effect of creating a
common denominator of the cement content.
An evaluation of the results yields the conclusions detailed in chapter Eight, the
principal two being:
• The optimal perlite grading tested was a monodisperse, single size fraction, of
between 600 and 1180 microns.
• The most practical measure for manufacturers to improve the performance of
lightweight<br>Andrew Chakane 2019
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Han, Hsieh Chung, and 謝宗翰. "Reserch on the Themeral Behavior of Reservoir Sediments under Heating and the Expansion Mechanism of Lightweight Aggregates." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/71471141942651632700.
Full textAbstract:
碩士<br>國立中興大學<br>土木工程學系<br>92<br>This study aims to investigate the generally properties of the fine sediments and its behavior under heating. In the meanwhile, the thermal expansion mechanisms of fine sediments lightweight aggregates are explored. The lightweight aggregates were sintered by using two laboratory kilns, and the physical properties and micro-structure analysis of the aggregates were then carried out. The characteristics of raw material and the heating conditions of sintered lightweight aggregates were evaluated based on the above results.
Test result shows that the main mineral composition of the reservoir fine sediments is quartz (56.5%). The chemical composition is suitable for sintering, and the physical properties, such as grain size (D50 = 0.003 mm) and plasticity (P.I. = 14), are also appropriate to produce expansible lightweight aggregates. Sintering temperature and duration affect the properties of aggregates obviously. If the aggregates with large expansion and low density are purposed, keeping the preheat temperature at 500℃ for 7.5 min and the sintering temperature at 1200℃ for 8~12 min are needed. On the other hand, the aggregates with lower porosity (0.9%) and water absorption (0.4%) can be produced while the sintering temperature is high and the duration is long. By the TGA-DTA test results, it can be inferred that the main materials that discharged gas are carbonate and the organic matter.
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Yi-ChongLiao and 廖邑崇. "Effects of heat treatment and fluxing agents on physical properties of lightweight aggregates from water reservoir sediment." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/25563092328152184790.
Full textAbstract:
博士<br>國立成功大學<br>資源工程學系碩博士班<br>100<br>Lightweight aggregates were produced from water reservoir sediment with various added flux agents including CaO, Na2CO3, NaOH, and Fe2O3. The result shows that Ca2+ and Na+ ions promoted the formation of glassy phase sealing the connecting pores in lightweight aggregates, reducing the water absorption of aggregates. More amount of glassy phase decreased the strength of aggregates and resulted in samples sticking to crucible. When the samples were taken off, the cracks was produced which increased the water absorption. Comparison to each flux ion, sodium ion substantially decreased the firing temperature for manufacturing lightweight aggregates. The aggregates produced from the sediment with added NaOH owned high strength performance due to the formation of geopolymer after the pre-curing process of the mixtures. The samples owned the property of geopolymer owning high strength performance though the bloating behavior occurred. The measurement of bulk density shows that the addition of Fe2O3 can not promote the bloating behavior, the bulk densities of the sample with added Fe2O3 are similar with those of samples without any added Fe2O3. Fe2O3 did not reduce into FeO to produce O2 gas, promoting bloating behavior, since no wuestite was found in XRD measurement, but hematite. The suitable condition for manuscript lightweight aggregates is employing faster heating rate (15 ºC/min) and longer duration time (30min), because faster heating rate results in more residue of carbon from the decomposition of organic matters increasing the production of gas and longer duration time results in a completing bloating behavior to produce aggregates with low bulk density.
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Lu, Chien-Hsing, and 呂建興. "Characterization of lightweight aggregates made from the bottom ash and fly ash of a fluidized-bed incinerator." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/gh4dqh.
Full textAbstract:
博士<br>國立中興大學<br>環境工程學系所<br>104<br>The properties of bottom ash and fly ash collected from a fluidized-bed (FB) incinerator for treating general municipal waste and general industrial waste were investigated. These bottom ash and fly ash were used for preparing artificial lightweight aggregates (LWAs) under different operating conditions. The physical properties such as the appearance, expansion rate, density, water absorption, ignition loss, and crushing strength, as well as the leaching rates of toxic heavy metals of these LWAs were explored. Furthermore, the differences of LWAs between the bottom ash and fly ash from a FB incinerator and a mechanical-bed (MB) incinerator were compared and discussed.
Experimental results showed that both the bottom ash and fly ash from the FB incinerator can meet the regulation limits of toxicity characteristic leaching procedure (TCLP). However, the fly ash from the cyclone and bag-house of the MB incinerator were identified as toxic wastes due to the concentrations of Cr and Pb over the TCLP regulation limits of Taiwan EPA. For preparing the LWAs, the fly ash from the different incinerators were mixed with the reservoir sediment and sintered. The results showed that the fly ash can be served as a fluxing and foaming agent, and the prepared LWAs can meet the TCLP regulation limits. The maximum mixing percentage of fly ash in the LWAs could be up to 15%. All the physical properties of the LWAs made from the FB fly ash were superior to those made from the MB fly ash.
The bottom ash of different incinerators were also used to replace the glass additive and mixed with the fly ash to prepare LWAs. The properties of these LWAs were analyzed and discussed. The results showed that the maximum mixing percentage of bottom ash in the LWAs was within the range of 65 - 75%, and that of fly ash was within 5 - 15%. The highest crushing strength of the LWAs made from the bottom ash and fly ash of the FB and MB incinerators were sintered at 1100oC and 1200oC, respectively. In addition, all the properties of LWAs made from the bottom ash and fly ash of FB incinerator were better than those of the MB incinerator.
The operating conditions of waste incinerators are the major factors influencing the physical and chemical properties of bottom ash and fly ash. Owing to the quartz sand being served as the fluidizing media, FB incinerator features the advantages of high mixing extent, high combustion efficiency, low ignition loss, and capturing heavy metals in bed. The concentrations of Si, Al, and Fe in both bottom ash and fly ash of the FB incinerator were high but the concentration of Ca in the fly ash was relatively low. Therefore, the FB fly ash was inherently viewed as the general (non-toxic) industrial waste. They can be directly reused in LWAs without any worry of secondary pollution. In addition, the optimal sintering temperature of LWAs made from the bottom ash and fly ash of the FB incinerator was lower than that made from the ashes of the MB incinerator. Therefore, the bottom ash and fly ash from FB incinerator exhibited superior physical and chemical properties to those of the MB incinerator. The bottom ash and fly ash of the FB incinerator displayed great reusing potentials and possibility.
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Sinha, Yash. "Production and Performance of Aggregates Using Two Types of Fly-ash for Lightweight Concrete using Glass Powder as Binder." Thesis, 2018. http://ethesis.nitrkl.ac.in/9850/1/2018_MT_216CE2056_YSinha__Production.pdf.
Full textAbstract:
In India despite the government commitment to increase energy production primarily by renewable sources and nuclear plants the main source for power production are coal fired thermal plants; its projected that by year 2020 India annual consumption of coal will rise to 1.5 billion tonnes. These coals fired thermal plants produce large quantity of finely divided fly-ash as by product which are collected be electrostatic precipitators from flue gases. Fly-ash in large quantities are still disposed of in landfills and storage lagoons. Such practices of disposal lead to environmental damage by causing air and water pollution on a large scale. Most of the previous research works were done by using conventional fine and coarse aggregates in concrete and replacing cement with fly-ash or by replacing the natural aggregates by fly-ash spherical aggregates. In this research work, the coarse aggregates were replaced entirely by fly ash angular aggregates in concrete.
For determination of physical properties tests like specific gravity, water absorption, etc. are performed on fly-ash, glass-powder, fine aggregates and coarse aggregates.
Fly-Ash aggregates are made from briquettes, which are casted by mixing glass powder and fly-ash in ratios of 10:90, 15:85 and 20:80 were adopted with a suitable water fly-ash ratio tried for every glass powder and fly-ash ratio. These briquettes after sintering were crushed to produce angular lightweight aggregates.
These lightweight aggregates performance were checked against sudden impact and progressive crushing by impact test and crushing test respectively.
Concrete mix design procedures recommended for lightweight aggregate concrete varies completely from normal aggregate concrete mix design. Lightweight aggregates are highly porous which has adverse effect on compressive strength and also reduces the free water available in paste matrix; so in the case of light weight concrete mixes the net water cement ratio required cannot be established with sufficient accuracy. The ACI standard ACI 213-03123 have suggested to overcome these difficulties by incorporating the concept of ‘Specific Gravity Factor’. In view of this lightweight concrete mixes are usually proportioned by trial and error method.
The mix design for fly-ash glass powder ratio of 15:85 was done for M20 grade concrete, because of the segregation problem natural aggregates are completely replaced by lightweight aggregates. In the fine trial compressive strength on 7th-day crossed the desired strength of 21 MPa requirement. Cubes are casted and tested for their compressive strength on 7th-day and 28th-day. Cylinders and Prisms are casted and tested on 28th Day for split tensile test and flexural strength test respectively.
From the studies, it can be concluded that the fly-ash aggregates can be used as a substitute of natural aggregates in construction works.
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Yang, Sheng-fan, and 楊勝帆. "The study of mixture for municipal sewage sludge with the ceramic tile polishing waste to be reused by forming the lightweight aggregates." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/38561262925950830412.
Full textAbstract:
碩士<br>國立聯合大學<br>環境與安全衛生工程學系碩士班<br>96<br>Accompanying with urban and civilization development, people environmental protection consciousness gains highly attention. Government side focus on river water quality improvement and constructing the sewerage system in recent years, the sewage sludge increased accordingly. The sanitary landfill for sludge increased the environment loading. To study the waste reused method for sludge is very urgent.
This research focuses on the forming characteristics at high tempera‐ture for city sewage sludge and the ceramic tile polishing powder waste. These two materials at the weighting ratio of 10%, 30%, 50%, and 70% separately at the temperature of 1,050℃, 1,075℃, 1,100℃, 1,125℃, at various times at holding temperatures for 5min, 10min, 20min were tested.
The results showed that the mixture of different sewage sludge and the ceramic tile polishing powder waste produced lightweight aggregate for the density less than 1.60 g/cm3, at the temperature of 1,125℃, the sewage sludge and time were controlled at 0%-20min, 10%‐10min/20min, 30% -5min/10min/20min,50%-5min/10min/20min and 70%‐5min/10min/20 min separately。It also showed that the water ratio increased can reduce the lightweight aggregate density and save energy required.
Sludge added to form light aggregate at the conditions of sintering temperature 1,125℃, 10min and occupied 30% ratio were used for producing concrete materials. The results showed that the lightweight aggregate concrete units was 1,760 kg/m3, 28days Compressive strength was 532 kgf/cm2, comparing with ASTM C330 structural lightweight concrete strength of 280 kgf/m2, showed this sintered lightweight aggregate has a higher strength characteristics and shows its excellent quality.
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(5930972), Chen Hsuan Chiu. "Screening of Microorganisms, Calcium Sources, and Protective Materials for Self-healing Concrete." Thesis, 2019.
Find full textAbstract:
<p>To make bacterial-based self-healing concrete, alkaline-resistant bacterial spores, nutrient sources, and a calcium source are incorporated into a concrete matrix. Two ureolytic spore-forming bacteria, <i>Sporosarcina pasteurii</i>, <i>Lysinibacillus sphaericus</i>, and two non-ureolytic spore-forming bacteria, <i>Bacillus cohnii</i>, and <i>Bacillus pseudofirmus</i>, which have been used in previous studies as bacterial concrete healing agents, were compared in this study. The four bacteria were compared for their (1) sporulation rates on different sporulation agar plates, (2) growth in five liquid media, (3) survival rates in light weight aggregates (LWA) and in mortar samples, and (4) calcium carbonate precipitation rates from either calcium lactate or calcium nitrate. Sporulation was successfully induced after three-day incubation at 30°C on an appropriate sporulation medium. High sporulation rates of <i>B. cohnii</i>, and <i>B. pseudofirmus</i>(93% and 99% respectively) were found on alkaline R2A medium (AR2A). A sporulation rate (89%) of <i>S. pasteruii</i>was observed on tryptic soy agar supplemented with 2% urea (TSAU)<i>.</i>The highest sporulation rate (60%) of <i>L. sphaericus</i>was found on R2A medium supplemented with 2% urea (R2AU). In the growth study, tryptic soy broth supplemented with 2% urea (TSBU) was a positive control which supported rapid growth of all four bacteria. <i>Sporosarcina pasteurii </i>and <i>L. pasteurii</i>showed rapid growth rates in alkaline yeast extract broth (AYE) and yeast extract with 2% urea broth (YEU) respectively. In contrast, <i>B. cohnii</i>, and <i>B. pseudofirmus</i>grew poorly in all media except in the positive control. Viable counts of the four bacterial spores reduced (1.8–3.3 logs) during the first 24 h in mortar samples and then remained stable for next 27 days testing period. Among the four, <i>S. pasteurii</i>showed the smallest reduction of viable counts (1.8–2.5 logs) in mortar after one day of incubation. Both <i>S. pasteurii</i>and <i>L. sphaericus</i>showed high CaCO<sub>3 </sub>productions (>80%) after 24 h incubation at 30°C in YEU containing either calcium nitrate or calcium lactate. However, <i>B. pseudofirmus</i>and <i>B. cohnii </i>showed<i></i>low calcite recovery rates (<11%) in AYE containing either<i></i>calcium nitrate or calcium lactate under the same incubation condition. Overall, <i>S. pasteurii</i>was the best bacterial concrete healing agent of the four. This bacterium had (1) rapid growth rate in AYE, (2) about 90% sporulation rate within 3 days, (3) highest survival rates after 24 h in mortar samples and, (4) high CaCO<sub>3 </sub>precipitation rates, 82 or 98%, in broth containing calcium nitrate or calcium lactate respectively.</p><p>In addition, two different lightweight aggregates (LWA), expanded shale (ES) and expanded clay (EC), which were used as bacterial carriers and protective materials, were compared in this study. Each type of LWA was separated into three sizes (<0.85 mm, 0.85– 2.0 mm, and >2.0 mm) and immobilized with spores of <i>B. cohnii</i>or <i>B. pseudofirmus.</i>Viable counts recovered from EC and ES reduced <1.0 log after the immobilization process and remained stable during the 150 days testing period. Neither the type nor the particle sizes of the two LWA significantly affected the survival rates of the bacterial spores. This result showed that both EC and ES could be used as carriers for bacterial healing agents. It was also found that when the spores were immobilized with nutrients in LWA, their survival rates in mortar samples can be improved slightly (<1.0 log).</p><p><br></p>
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Chou, Yung-Lung, and 周永龍. "Alkali-Aggregate Reaction of Artificial Lightweight aggregate concrete." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/17141993864197330414.
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