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Pospíšilík, Štěpán. "Návrh marketingové strategie firmy Liquid Design, s.r.o." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2011. http://www.nusl.cz/ntk/nusl-223180.
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This thesis is focused on analyzing the current situation of Liquid Design s.r.o. engaged in information technology and proposal new marketing strategies. In the first part there are chapters depicting the theoretical background needed to create an appropriate marketing strategy. The second part is devoted to analysis of the current state of Liquid Design s.r.o., namely its marketing strategy. The third and final part of this thesis includes a proposal for a new marketing strategy that aims to reach new customers and retain the existing ones.
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Hudaib, Ala'. "Asphalt Mix Design for Low Volume Roads." University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1619752960078631.
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Ghasemi, Yahya. "Aggregates in Concrete Mix Design." Licentiate thesis, Luleå tekniska universitet, Byggkonstruktion och -produktion, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-61659.
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The importance of studying the behaviour and properties of concrete can be highlighted by considering the fact that concrete is the most used man-made material in the world. The very first step in making concrete is its mix design and deciding the type and amount of constitutes used in the production of concrete which should fulfil the requirements of the final product. Mix design models are commonly used for the purpose of proportioning concrete ingredients while anticipating the properties of the final product. The current document deals with the commonly used principals in mix design models namely particle packing theory and excess water/paste layer theories. The conducted studies includes an investigation on accuracy of particle packing models (Toufar, 4C, CPM) and also tries to address the issue with measurement of specific surface area of particles as an essential input to water/paste layer theories. It has been observed that the particle packing models can predict the packing density with acceptable margin. However, it should be mentioned that the particle packing models by themselves are not mix design models but should be rather used as a part of a mix design. In addition, it was found that the accuracy of calculating the specific surface area of particles based on their size distribution curve can be further improved by assuming angular platonic solids as uniform shape of aggregate instead of traditional approach of assuming spheres for aggregates’ shape.
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Veisi, Maryam. "Accelerated mix design of stabilized subgrades." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Stoklasová, Adriana. "Komunikační mix podniku." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2019. http://www.nusl.cz/ntk/nusl-402069.
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The thesis deals with the design of communication mix for FLEA micropho-nes. It explains important terms and principles related to current marketing issues. Then there is a detailed analysis of the current state of the company and a concrete pro-posal of the communication mix is created.
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Stubbs, Anthony Pooley. "Fatigue Behaviour of Hot Mix Asphalt for New Zealand Pavement Design." Thesis, University of Canterbury. Civil and Natural Resources Engineering, 2011. http://hdl.handle.net/10092/6520.
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Asphalt’s fatigue and modulus characteristics play an important role in pavement design. Ultimately they govern the required thickness of asphalt to structurally support heavy vehicles. The thickness of the asphalt layer is a major contributor to the cost of construction. In New Zealand, the design of structural asphalt layers has been a problem for some time and gives rise to two areas of concern. First, the present fatigue failure criterion, the Shell fatigue transfer function, which has been adopted from overseas, not only underestimates the fatigue life of the country’s asphalts, but does not accurately characterise the fatigue behaviour of our local asphalt mixes. Consequently, asphalt thicknesses are overdesigned. Second, asphalt’s fatigue behaviour is influenced by numerous factors and therefore can be difficult to characterise. The primary objective of this thesis is to develop fatigue and modulus models, by carrying out fatigue and modulus tests, to characterise the behaviour of two typical New Zealand structural asphalts. Both resilient and stiffness moduli tests were performed at a range of temperatures and loading rates developing moduli master curves, which predict the asphalt’s modulus for any pavement temperature and vehicle speed. A general full factorial experiment was carried out utilising the four-point flexural beam fatigue test. Tests were carried out at different strain levels, temperatures, and loading rates. An analysis of variance showed that the impacts of strain amplitude, temperature, binder type, the interaction of strain amplitude and temperature, and the interaction of strain amplitude and binder type have a significant effect on fatigue behaviour. The developed models, which account for temperature effects give the pavement engineer the ability to undergo a more accurate assessment of fatigue damage than at present for different climatic temperatures demonstrated by using an incremental damage analysis approach. The research shows that with such characterisation for the given pavement’s design life, thinner and less expensive roads can be constructed in New Zealand.
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Li, Ying. "Digital Mix Design for Performance Optimization of Asphalt Mixture." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/72959.
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Asphalt mix design includes the determination of a gradation, asphalt content, other volumetric properties, the evaluation of mechanical properties and moisture damage potentials. In this study, a computational method is developed to aid mix design. Discrete element method (DEM) was used to simulate the formation of skeleton and voids structures of asphalt concrete of different gradations of aggregates. The optimum gradation could be determined by manipulating the particle locations and orientations and placing smaller particles in the voids among larger particles. This method aims at an optimum gradation, which has been achieved through experimental methods. However, this method takes the mechanical properties or performance of the mixture into consideration, such as inter-aggregate contacts and local stability. A simple visco-elastic model was applied to model the contacts between asphalt binder and aggregates. The surface texture of an aggregate particle can be taken into consideration in the inter-particle contact model. The void content before compactions was used to judge the relative merits of a gradation. Once a gradation is selected, the Voids in Mineral Aggregate (VMA) can be determined. For a certain air void content, the mastics volume or the binder volume or the asphalt content can be determined via a digital compression test. The surface area of all the aggregates and the film thickness can be then calculated. The asphalt content can also be determined using an alternative approach that is based on modeling the inter-particle contact with an asphalt binder layer. In this study, considering the necessity of preservation of the compaction temperature, the effect of various temperatures on Hot Mix Asphalt (HMA) samples properties has been evaluated. As well, to evaluate the effect of this parameter on different grading, two different grading have been used and samples were compacted at various temperatures. Air voids also influence pore water pressure and shrinkage of asphalt binder and mixture significantly. The shrinkage is measured on a digital model that represents beams in a steel mold and is defined as the linear autogenous deformation at horizontal direction.Ph. D.
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Nanagiri, Yamini Varma. "Development of a rational method of designing hot mix asphalt (HMA) for low volume roads." Link to electronic thesis, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-01055-115823/.
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Sangiorgi, Luca. "Nuovi calcestruzzi geopolimerici: Mix design, caratterizzazione e fattibilita in cantiere." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/9201/.
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I cambiamenti climatici dovuti all’immissione in atmosfera dei gas serra costringono alla ricerca di possibili soluzioni per la loro riduzione. Una risposta potrebbe essere rappresentata dall’impiego di calcestruzzi geopolimerici in quanto riducono notevolmente l’emissione in atmosfera di anidride carbonica rispetto ai calcestruzzi tradizionali.
In letteratura sono numerosi gli studi di calcestruzzi geopolimerici realizzati mediante trattamenti termici applicati dopo le operazioni di confezionamento. Pochissime sono invece le ricerche effettuate su calcestruzzi geopolimerici prodotti senza trattamenti termici; in questa tesi sperimentale si è voluto indagare quest’ultimo tipo di conglomerati. In particolare si è studiato il mix design del calcestruzzo geopolimerico partendo dalla formulazione del calcestruzzo tradizionale. Da subito si è posto il problema di quale agente riduttore di acqua utilizzare. Pertanto è stata predisposta una sperimentazione di diversi tipi di fluidificanti e superfluidificanti su campioni di malta geopolimerica. In seguito sono stati testati diversi conglomerati geopolimerici con propri mix design, derivati in parte da esempi in letteratura, al fine di conseguire un accettabile valore di resistenza meccanica a compressione.
Nella prospettiva di un possibile utilizzo in cantiere è stata indagata con particolare attenzione, la lavorabilità delle malte e dei calcestruzzi geopolimerici attraverso prove di consistenza, ponendola in relazione alle malte e i calcestruzzi cementizi.
Sono state inoltre analizzate le caratteristiche dei materiali prodotti allo stato indurito, quali densità, assorbimento di acqua, modulo elastico e resistenza meccanica.
Infine, è stata analizzata la fattibilità di un possibile utilizzo in cantiere.
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Blanková, Barbora. "Analýza komunikace v procesu změny korporátní identity organizace." Master's thesis, Vysoká škola ekonomická v Praze, 2013. http://www.nusl.cz/ntk/nusl-193751.
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The topic of the thesis is a change of corporate identity of the company and role of communication during this process. There are components of corporate identity and relationship between corporate identity, image and reputation described in the thesis. Furthermore it is dedicated to integrated marketing communication, internal communication and role of communication in change management. The theoretical knowledge is applied on company Nicoll Česká republika, s.r.o. which have been coming through the changes of name and corporate identity since January 2015. The main goal is to describe in detail and analyze the process of this change from the preparation phase to realization with respect on communication, evaluate this communication and suggest further recommendations. The analysis contains of description of the company including former communication mix, furthermore there is a description and analysis of changes and also analysis and evaluation of communication. In the end of the thesis there are summarized the main problems connected with the changes and also key mistakes, which were done in communication. Finally it suggests further steps for future.
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Khaewsukkho, Smart. "New Approaches for Design of High-Mix Low-Volume Facilities." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1211984904.
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Siegel, Timothy C. "Correlation of mix characteristics with rutting in bituminous mixes." Thesis, Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/19552.
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Robinson, William Jeremy. "Design and Performance of Open Graded Friction Course Hot Mix Asphalt." MSSTATE, 2005. http://sun.library.msstate.edu/ETD-db/theses/available/etd-03312005-101655/.
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Open-graded friction course (OGFC) is a porous mix primarily used to improve pavement safety. OGFC is characterized by air voids ranging from 15 to 20 percent which allows surface water to drain through its structure and then laterally from the pavement structure. The ability of OGFC to drain water quickly results in less water ponding on the pavement surface, thereby reducing hydroplaning, reducing vehicle spray, and providing improved skid resistance. Research objectives were to evaluate the use of OGFC mixes containing 100 percent gravel and 50 percent gravel/50 percent limestone and to determine specifications to be employed by the Mississippi Department of Transportation (MDOT). Specimens were prepared at design asphalt binder content and evaluated for permeability, durability, stability, and moisture resistance. Research findings show mixes containing 100 percent gravel and 50 percent gravel/50 percent limestone perform comparably in laboratory testing.
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Subramanian, Arunkumar. "Analysis of the design and operation of mix-bank resequencing areas." MSSTATE, 2004. http://sun.library.msstate.edu/ETD-db/theses/available/etd-08062004-162540/.
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Automotive assembly plants work on a pre-planned job sequence in order to optimize the performance of the assembly line. However, the job sequence becomes scrambled due to factors such as plant layout, process design, variability and uncertainty. Assembly plants use either a mix-bank or an automatic storage and retrieval system to regenerate the sequence before final assembly. A mix-bank, which is a set of parallel lanes, is the most common method used in the automotive industry to reconstruct the sequence. Only the first vehicles on the lanes are available for sequencing in a mix-bank set-up. Hence the lane selection policy and the lane configuration of a mix-bank play crucial roles in recreating the sequence. This thesis addresses the problem of identifying a superior lane selection policy for a mix-bank re-sequencing area. Simulation models of a re-sequencing area are used to evaluate lane selection policies. Varying the lane configurations and the nature of sequence tests the effectiveness of the selection policies.
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Robati, Masoud. "Evaluation of a modification of current micro-surfacing mix design procedures." Mémoire, École de technologie supérieure, 2012. http://espace.etsmtl.ca/980/1/ROBATI_Massoud.pdf.
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Cette etude porte sur la modification des procedures de formulation de la International Slurry
Surfacing Association (ISSA) pour les traitements de surface. Les procédures actuelles de
formulation de traitement de surface ont été évaluées en détails. La première partie de ce
travail démontre l’effet de la quantité d’émulsion, d’eau d’apport et de l’utilisation d’additifs
(ciment) sur les paramètres de formulation des traitements de surface. La deuxième partie
consiste principalement en l’établissement d’une méthode de formulation optimale selon
quatre essais de l’ISSA, soit le TB 139, le TB 113, le TB 100 et le TB 109. Les résultats ont
montrés que le TB 139 peut être utilisé pour trouver la teneur en eau optimale et que l’essai
ISSA TB 147 devrait être utilisé pour trouver la teneur en émulsion optimale.
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Sampaio, Zodinio Laurisa Monteiro. "Low cement structural lightweight concrete with optimized multiple waste mix design." PROGRAMA DE P?S-GRADUA??O EM CI?NCIA E ENGENHARIA DE MATERIAIS, 2017. https://repositorio.ufrn.br/jspui/handle/123456789/24353.
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The high-energy demand involved in the construction industry and the increasing consumption of concrete made this material an ideal option for the recycling of by-products from various industries such as: porcelain polishing residue (PPR); tire rubber residue (TRR) and limestone residue (LSR). These residues often lack a treatment that contributes to the degradation of the environment. In this sense, the use of by-products that increases the volume of the concrete without damaging significantly its properties, can be a viable option in the production of low-cost and sustainable low-weight concrete (LWC). The main objective of this work was to analyze the mechanical and thermal behavior of structural lightweight concrete (SLWC) with low cement consumption, produced with expanded clay (EC) in replacement of the aggregate and with the addition of PPR, TRR and LSR to replace the small aggregate. For this purpose, a 2? factorial design was used for the choice of SLWC with the best performance in terms of consistency, mechanical properties and density. Subsequently, reductions of 10, 20 and 30% of cement were performed on SLWC that presented better combination of properties and waste consumption and were characterized by mechanical tests. The best SLWC mix resulting from the combination of mechanical properties and cement consumption was characterized by permeability, flexural strength, TG/DTA, XRF, SEM, thermal capacity, thermal conductivity and thermal diffusivity. The results showed that residues contents around 21% presented better combination of properties. By maintaining the amount of residue at optimum levels it was possible to produce a SLWC with good rheological, mechanical and thermal properties with minimum cement consumption.
A alta demanda energ?tica envolvida na ind?stria da constru??o civil e o crescente consumo do concreto, fez com que o concreto se tornasse a op??o ideal para a reciclagem de subprodutos de v?rias industrias tais como: res?duo de polimento de porcelanato PPR; res?duo de borracha de pneu (TRR) e res?duo de pedra calc?ria (LSR). Esses res?duos frequentemente carecem de um tratamento adequando o que acaba contribuindo para a degrada??o do meio ambiente. Nesse sentido, o uso de subprodutos que ir?o aumentar o volume do concreto sem prejudicar muito as propriedades, pode ser uma op??o bastante vi?vel na produ??o de Concretos leves (CL) de baixo custo e sustent?veis. O objetivo geral desse trabalho foi analisar o comportamento mec?nico e t?rmico de concretos leves estruturais (CLE) de baixo teor de cimento produzidos com argila expandida (AE) em substitui??o ao agregado gra?do e com adi??o de PPR, TRR e LSR em substitui??o a parte do agregado mi?do. Para tal foi usado inicialmente um planejamento fatorial 2? para a escolha dos CLE com melhor desempenho em termos de consist?ncia, propriedades mec?nicas e massa espec?fica real. Posteriormente foram realizadas redu??es de 10, 20 e 30% de cimento nos CLE que apresentaram melhores desempenhos e caracterizados atrav?s de ensaios mec?nicos. O melhor tra?o resultante da combina??o de propriedades mec?nicas com o consumo de cimento foi caracterizado mediante ensaios de: permeabilidade; resist?ncia ? flex?o; TG/DTA; FRX; MEV; capacidade t?rmica; condutividade t?rmica e difusividade t?rmica. Por fim. Os resultados mostraram que teores de res?duos em torno de 21% apresentaram melhor combina??o de propriedades. Mantendo os teores de res?duos em n?veis ?timos foi poss?vel produzir um CLE com boas propriedades reol?gicas, mec?nicas e t?rmicas com um consumo m?nimo de cimento.
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Vizzari, Domenico. "Mix-design of a novel semi-transparent layer for solar roads." Thesis, Ecole centrale de Nantes, 2020. http://www.theses.fr/2020ECDN0023.
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Le réseau routier du futur ne sera pas simplement un système de transport pour les utilisateurs et les biens, mais aussi une technologie pour la récupération d'énergie, profitant des surfaces existantes. Cette thèse traite de la formulation d'une couche semitransparente pour les routes solaires. La nouvelle surface est un matériau composite constitué de granulats de verre lié entre eux par une colle polyuréthane. A l’heure actuelle il n'existe aucune préconisation pour l’emploi de liant polyuréthane sur les couches de surface. Pour cette raison, 4 colles polyuréthanes sont caractérisé en termes de cinétique de polymérisation et de propriétés viscoélastiques. La recherche se focalise ensuite sur la formulation de la couche semi-transparente en se basant sur trois méthodes/techniques: la compacité de l’empilement granulaire, le plan d’expérience et la technique de l’enduit superficiel. L'objectif est l'optimisation à la fois optique et mécanique du matériau, dans la perspective d'une application à l’echelle 1. La dernière étape est la compréhennsion du vieillissement de la colle par le rayonnement solaire au moyen des techniques FTIR, DSC et rhéomètre rotationnel. La formulation de la couche semi-transparente est une étape importante vers la réalisation de la "route hybride", un système dédié à la récupération d'énergie né de l'union d'une route photovoltaïque avec un milieu poreux capable d'extraire de l'énergie temrique au moyen d'un fluide caloporteurThe road network of the future will be not only a transportation system for people and goods, but also a technology able to harvest energy from the Sun exploiting existing surfaces. This manuscript deals with the mixdesign of a semi-transparent layer for solar roads. The novel surface is a composite material given by recycled glass aggregates bonded together using the polyurethane. At present, there are no specifications or guidelines for the use of the polyurethane in solar roads. In the light of this, the polyurethane is characterized in terms of curing kinetic and viscoelastic behavior performing the DSR and the DMA. The research also focuses on the mix-design of the semi-transparent layer based on three methods/techniques: the packing density, the fraction factorial design and the surface dressing. The objective is to optimize the optical and mechanical performance of the mixture, in the prospective of a full scale application. Finally, the aging of the polyurethane because of the UV exposition is investigated by means of the FTIR, the DSC and the rotational rheometer test. The mix-design of the semi-transparent layer is an important step towards the manufacture of the “hybrid road”, a road energy harvesting system obtained by the union between a concrete porous medium used as solar collector with a photovoltaic road
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Kuna, Kranthi. "Mix design considerations and performance characteristics of foamed bitumen mixtures (FBMs)." Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/28857/.
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The sustainability issues in pavement materials and design form a strong incentive for the present work. Using recycled materials in pavements is a sustainable practice that is gaining adoption, particularly for flexible (bituminous) pavements. One approach is to incorporate large quantities of Reclaimed Asphalt Pavement (RAP) into base and sub-base applications for pavement construction. Numerous studies have reported that RAP can be reused as an aggregate in Hot Mix Asphalt (HMA) as well as in cold mix asphalt, granular base, sub-base, and subgrade courses. Cold recycling technology, like hot mix technology, has also become popular in various countries for rehabilitation of damaged bituminous pavements. RAP stabilized with bitumen emulsion and foamed bitumen has been used as a base layer. The present study focuses on Foamed Bitumen treated Mixes (FBMs). Most of the agencies which use FBMs have their own mix design procedures which are the result of numerous efforts over decades. In spite of all these efforts, Foamed Bitumen application in cold recycling in the United Kingdom suffers from the lack of a standardised mix design procedure. To overcome this, the present research objective was to develop a mix design procedure by identifying critical mix design parameters. The mix design parameters that were optimised were Foamed Bitumen content, mixing water content (MWC), and compaction effort. Special attention was given to the simplest yet crucial mix design consideration of FBMs; curing. The thesis also attempted to simulate what should be expected in terms of the performance of flexible pavements containing FBMs as road base. The mix design parametric study was initially carried out on FBMs with virgin limestone aggregate (VA) without RAP material and a mix design procedure was proposed. Optimum MWC was achieved by optimising mechanical properties such as Indirect Tensile Stiffness Modulus (ITSM) and Indirect Tensile Strength (ITS-dry and ITS-wet). A rational range of 75-85% of Optimum Water Content (OWC) obtained by the modified Proctor test was found to be the optimum range of MWC that gives optimum mechanical properties for FBMs. The proposed methodology was also found to apply to FBMs with 50% RAP and 75% RAP. It was also found that the presence of RAP influenced the design FB content, which means that treating RAP as black rock in FBM mix design is not appropriate. This work also evaluated the validity of the total fluid (water + bitumen) concept which is widely used in bitumen-emulsion treated mixes. The present work was also intended to better understand the curing mechanism of FBMs and to lessen the gap between laboratory curing and field evolution of these mixtures. This was achieved by evaluating different curing regimes that are being followed by different agencies and researchers, as well as identifying important parameters that affect curing. In achieving this, a link was established between laboratory mix design and field performance by evaluating applicability of the maturity method. The curing regime study provided a valid investigation into the behaviour of FBM taking into account the effect of temperature, curing conditioning (Sealed or Unsealed), curing duration and the influence of cement with different curing regimes. It was found that the temperature is as important a parameter as time, as temperature has a greater influence on curing rate and also on bitumen properties. Moreover, higher curing temperatures resulted in higher rate of stiffness gain. This trend is not only because of rapid water loss but also implies an increase in binder stiffness at higher curing temperatures. Though the presence of RAP improved the early stage stiffness of FBMs, it slowed down the rate of water loss from the specimens which resulted in smaller stiffness values at a later stage. The experimental results also indicated that cement addition has no influence on water loss trends, but improved the stiffness significantly during all stages of curing. The study also evaluated the applicability of the maturity method as a tool to assess the in-situ characteristic of FBM layers in the pavement. It was found that replacing the time term with an equivalent age term in the maturity function aided in estimating stiffness rather than relative stiffness. This was possible because of the characteristic curing of FBM in which the limiting stiffness these mixtures reach strongly depends on the curing temperature at least for the length of the curing stages considered in the present study. A strong correlation was found between maturity and the stiffness values obtained from the laboratory tests which resulted in development of maturity-stiffness relationships. The application of the method to assess the in-situ stiffness was presented using three hypothetical pavement sections. The results showed the influence of ambient temperature and the importance of cement addition to FBMs. The permanent deformation resistance was assessed by performing RLAT tests on cylindrical specimens compacted by gyratory compactor. The RLAT test results indicate that both test temperature and stress level have significant influence on permanent deformation characteristics as expected. The effect of stress on permanent deformation was increased with increase in test temperature. It was also found that from limited tests and mixture combinations, RAP content has only a slight influence on permanent deformation of FBMs. However, the presence of cement led to significant improvement. FBMs were also found to be less temperature susceptible than HMA in terms of permanent deformation and, within FBMs, mixtures with cement were found to be more sensitive than FBMs without any cement. For assessing the fatigue performance of FBMs, the ITFT was initially used to investigate the effect of cement on the fatigue life. The ITFT tests results showed that the FBMs without cement (50%RAP-FBM) have lower fatigue life than HMA (DBM90) at any initial strain level. Nevertheless, similar to permanent deformation, the fatigue life was improved with the addition of 1% cement to FBMs. However, the above discussion was not found to be completely valid when uniaxial tests were carried out. In stress controlled uniaxial tests, a sinusoidal load of 1Hz frequency was applied axially to induce tensile strain in the radial direction. The failure criterion considered in the study was the number of cycles to reach 50% stiffness and this was plotted against the measured initial strain values. Results indicated that there was not much difference in fatigue life among different mixtures and also between FBM and HMA. However, stiffness evolution curves showed that FBMs fail in a different pattern compared to HMA. Unlike HMA, which showed a three stage evolution process, for FBMs the stiffness actually increased initially to reach a maximum and decreased at a slower rate until failure. It was also found that by plotting curves according to Hopman et al.,(1989) which identifies the fatigue failure transition point, use of the 50% stiffness criterion for fatigue life evaluation is not a conservative approach. Uniaxial tests also revealed that, although in fatigue the FBMs were found to behave differently from HMA, in terms of permanent deformation, FBMs behave similarly to HMA in that a steady state strain rate was achieved.
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Brégeon, Lalanne de Saint-Quentin Virginie. "Un mix design expérientiel-culinarité au service du ravissement du consommateur." Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1G006/document.
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La notion de culinarité est « dans toutes les bouches » sans avoir été l'objet d'une définition en marketing et comportement du consommateur. Pour combler cette lacune, cette thèse s’est attachée à explorer les contours de la culinarité et proposer un mix design expérientiel x culinarité au service du ravissement du consommateur. Après de premières explorations basées sur des analyses de contenus sur internet (NGram Viewer et Google) et des entretiens semi-directifs qui ont affiné la compréhension du concept, la recherche a consisté en une analyse polymorphe des dimensions et pratiques autour de la notion de culinarité. S'appuyant sur une multiangulation des terrains de recherche, les quatre études empiriques ont été : 1) des études de cas au Grand Restaurant ; 2) une observation participante d’un Mooc en design culinaire ; 3) des manipulations de la culinarité au restaurant ; 4) trois expérimentations sous forme de restaurants éphémères, supports d’une enquête et d’observations. Dès lors, les conclusions apportées proposent une définition de la culinarité (déterminant Plaisir et 4 dimensions QCSP : Q-Qualité, C-Créativité, S-Savoir-Faire, Partage), confirmant l’intérêt d’un mix design expérientiel x culinarité pour ravir le consommateur et introduisent ce que serait le marketing culinaireThe culinary is in everybody’s mouth without having been defined neither in marketing or in the field of consumer’s behavior. In order to limit this lack of concept, this thesis aims at exploring the ideas behind the culinary and to suggest a mix experiential design x « culinariness » for a consumer’s delightment. After the first exploration based on content analysis on the internet (NGram Viewer and Google) and semi-directive interviews that have revealed part of the concept, the research consisted in a polymorphic analysis of the dimensions and uses of the culinary. Built on a multiangulation of the research, the four empirical studies were : 1) case studies of quality restaurants ; 2) participating observation of a Mooc on food design ; 3) tests on the dimensions of the culinary at the restaurant ; 4) three experimentations as pop up restaurants enabling somes observations on spot and investigations. Thus, the results of this study lead to a definition of the culinary (Pleasure as a determinant and 4 dimensions QCKS: Q-Quality ; C-Creativty ; K-Know-how ; S-Sharing). They attest the point of an experiential design x culinary mix in order to delight the consumer and introduce a culinary marketing
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AHMAD, SAJJAD. "Innovative mix design of cementitious materials for enhancing strength and ductility." Doctoral thesis, Politecnico di Torino, 2015. http://hdl.handle.net/11583/2604771.
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Cement based composites i.e. paste, mortar and concrete are the most utilized materials in the construction industry all over the world. Cement composites are quasi-brittle in nature and possess extremely low tensile strength as compared to their compressive strength. Due to their low tensile strength capacity, cracks develop in cementitious composites due to the drying shrinkage, plastic settlements and/or stress concentrations (due to external restrains and/or applied stresses) etc. These cracks developed at the nanoscale may grow rapidly due to the applied stresses and join together to form micro and macro cracks. The growth of cracks from nanoscale to micro and macro scale is very rapid and may lead to sudden failure of the cement composites. Therefore, it is necessary to develop such types of cement composites possessing higher resistance to crack growth, enhanced flexural strength and ductility.
The development of new technologies and materials has revolutionized every field of science by opening new horizons in production and manufacturing. In construction materials, especially in cement and concrete composites, the use of nano/micro particles and fibers in the mix design of these composites has opened new ways from improved mechanical properties to enhanced functionalities. Generally, the production or manufacturing processes of the nano/micro sized particles and fibers are energy intensive and expensive. Therefore, it is very important to explore new methods and procedures to develop less energy intensive, low cost and eco-friendly inert nano/micro sized particles for utilization in the cement composites to obtain better performance in terms of strength and ductility.
The main theme of the present research work was to develop a family of new type of cementitious composites possessing superior performance characteristics in terms of strength, ductility, fracture energy and crack growth pattern by incorporating micro sized inert carbonized particles in the mix design of cementitious composites. To achieve these objectives the micro sized inert carbonized particles were prepared from organic waste materials, namely: Bamboo, coconut shell and hemp hurds. For comparison purposes and performance optimization needs, another inorganic waste material named as carbon soot was also investigated in the present research.
The experimental investigations for the present study was carried out in two phases; In the first phase of research work, a methodology was developed for the synthesis of the micro sized inert carbonized particles from the above mentioned organic raw materials. In the second phase of research, various mix proportions of the cementitious composites were prepared incorporating the synthesized micro sized inert carbonized particles. For micro sized inert carbonized particles obtained from bamboo and coconut shell three wt.% additions i.e. 0.05, 0.08, 0.20 were investigated and for particles synthesized from hemp hurds 0.08, 0.20, 1.00 and 3.00 wt.% additions were explored.
The cement composites were characterized by third-point bending tests and their fracture parameters were evaluated. The mechanical characterization of specimens suggested that 0.08 wt.% addition of micro sized inert carbonized bamboo particles enhances the flexural strength and toughness of cement composites up to 66% and 103% respectively. The toughness indices I5, I10 and total toughness of the cement composites were also enhanced. The carbonized particles synthesized from coconut shell resulted in improved toughness and ductility without any increase in the modulus of rupture of the cement composite specimens. Maximum enhancements in I5 and I10 were observed for 0.08% addition of both carbonized and carbonized-annealed particles. For the carbonized hemp hurds cement composites the results indicate that the micro sized inert carbonized particles additions enhanced the flexural strength, compressive strength and the fracture energy of the cement composites.
The microstructure of the cement composites was also studied with the help of field emission scanning electron microscope (FESEM) by observing small chunks of cement composite paste samples. The FESEM observations indicated that the micro sized inert carbonized particles utilized in the mix design of these mixes were well dispersed in the cement matrix. It was also observed that the fracture paths followed by the cracks were tortures and irregular due the presence of micro particles in the matrix. The cracks during their growth often contoured around the inert particle inclusions and resulted in enhanced energy absorption capacity of the cement composites.
The study was further enhanced to the cement mortar composites and their performances were studied. The results indicated that the energy absorption behavior of the composites was enhanced for all the cement composites containing micro carbonized particles.
Finally, it is concluded that the ductility and toughness properties of the cement composites can be enhanced by incorporating the micro sized inert carbonized particles in the cement matrix. The fracture energy, ductility and toughness properties enhancement of the cement composites greatly depends upon the source and synthesis procedure followed for the production of micro sized inert carbonized particles.
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Schweiger, Ronja. "Adamant Textile : The reciprocal impact of concrete and textile." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-14891.
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The primary goal of this study is to investigate the combination of concrete merged with textiles. Furthermore, it investigates exchanging the characteristics of these contrasting materials. Consequently, the work shows the reciprocal influence of both textile and concrete to each other. The resulting final collection presents six pieces with the main intention to present different expressions of flexibility. These appear through the interaction of textile and concrete, with the textile providing the flexibility. Depending on the precise characteristics of the used textiles, the flexibility can be shown through the tension in a fabric, the ability to be squeezed or the movement. A subsequent range of experiments investigates techniques, methods and material qualities to prove, that the required effects of the end result can be fulfilled. The crucial factors are the textile materials, the connection between concrete and textile and the treatment of the resulting surface or object. Depending on which way the crucial components are fused, a variety of expressions in the results can be accomplished. These can be described as rather organic through to geometric, and also depends whether the piece is in motion. The outcomes provide an overview of design possibilities, of incorporating such contrasting materials to create different properties and unexpected characteristics in each piece. Based on the final results, it can be concluded that the major objective, to explore design possibilities through a reciprocal interaction of textile and concrete, gives a strong and impressive expression. The approach of this relatively broad research is nevertheless important for the textile field. Therefore, it suggests further exploration, using the results as a foundation and narrow it down by focusing on specific factors.
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Jacobson, Jesse Richard. "Factors Affecting Strength Gain and Development of a Laboratory Testing Procedure." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/32298.
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Lime-cement columns were constructed to improve soft ground at the I-95/Route 1 Interchange in Alexandria, Virginia. As part of the test embankment program, two different commercial laboratories performed laboratory tests on treated soil, and they produced strikingly different unconfined compression test results. Further, both sets of results are different from test results for similar soils available in the published literature. This situation created uncertainties and a conservative design philosophy, accompanied by increased construction costs compared to typical lime-cement column projects. The goals of this research project were to assess factors that influence strength gain of lime-cement-soil mixtures and to develop a detailed laboratory test procedure that produces consistent results. Key findings from the research are that a laboratory test procedure that produces consistent results has been developed, drying and subsequent restoration of soil moisture prior to treatment can decrease the strength of the mixture, the mixture strength decreases as the ratio of soil water content to cement content increases for 100 percent cement-soil mixtures, the addition of lime can increase the mixture strength for some soils and decrease the strength for others, and presenting the test results in the form of contour plots of unconfined compressive strength can be very useful.Master of Science
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Linhartová, Štěpánka. "Analýza komunikačního mixu Zoo Praha." Master's thesis, Vysoká škola ekonomická v Praze, 2007. http://www.nusl.cz/ntk/nusl-13310.
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Práce je rozdělena na teoretickou a praktickou část. V teoretické části jsou vysvětleny pojmy jako komunikační mix a jeho složky, hlavně pak reklama a public relations. Dále pak pojem vizuální styl a jeho tvorba. V praktické části je podroben analýze komunikační mix Zoo Praha z let 2002 - 2007, s důrazem na jednotný vizuální styl, který se komunikačním mixem prolíná.
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Owusu, Twumasi Jones. "PREDICTION OF 28-DAY COMPRESSIVE STRENGTH OF CONCRETE USING RELEVANCE VECTOR MACHINES (RVM)." OpenSIUC, 2013. https://opensiuc.lib.siu.edu/theses/1141.
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Early and accurate prediction of the compressive strength of concrete is important in the construction industry. Modeling the compressive strength of concrete to obtain a balance and equality between prediction accuracy, time and uncertainty of the prediction is a very difficult task due to the highly nonlinear nature of concrete. For structural engineering purposes, the 28- day compressive strength is the most relevant parameter. In this study, an attempt has been made to predict the 28-day compressive strength of concrete using Relevance Vector Machine (RVM). An RVM belongs to the class of sparse kernel classifiers, which are powerful tools in classification and regression. It has a model of identical functional form to the popular and state-of-the-art `Support Vector Machine (SVM)'. The benefits of using RVM include automatic estimation of nuisance parameters, probabilistic prediction and the ability to model complex data with little information. A total of 425 different data of high performance mix designs were collected from the University of California, Irvine repository. The data used to predict the compressive strength consisted of nine components. The RVM model was trained and tested using 395 and 30 data sets respectively. The model's performance was assessed at the end of the training and testing period using four performance measures; coefficient of determination, root-mean-square error, percentage of relevance vectors and residual plots. All the performance measures confirmed the accuracy of the model. The results of the study suggested that RVM is an effective tool for predicting the 28- day compressive strength of concrete from its mix ingredients.
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Koubek, Filip. "Návrh komunikačního mixu vybraného podniku." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2017. http://www.nusl.cz/ntk/nusl-319242.
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The thesis is focused on proposal of communication mix for the motion design company. This contains the most important concepts and principles related to the current issues of marketing in the advertising segment. Furthermore, a detailed analysis of the current state of the company and created a specific proposal of new communication mix, which should lead the fulfillment of the objectives set.
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Gao, Xiang, and S3090502@student rmit edu au. "Mix Design and Impact Response of Fibre Reinforced and Plain Reactive Powder Concrete." RMIT University. Civil, Environmental and Chemical Engineering, 2008. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080424.150722.
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Concrete is the most broadly used material in construction worldwide and Reactive Powder Concrete (RPC, a type of ultra high performance concrete) is a relatively new member of the concrete family. In this work the critical parameters of RPC mix design are investigated and the mix design is explored through a program of concrete casting and testing. Owing to the enhanced microstructure of RPC, porosity and permeability can be significantly decreased in the concrete matrix. This benefits the durability characteristics of RPC elements resulting in a longer service life with less maintenance costs than conventional concrete. It has been used for high integrity radiation waste material containers because of its low permeability and durability. Fibre reinforced RPC is also ideal for use in long span and thin shell structural elements without traditional reinforcement because of its advantageous flexural strength. Moreover, due to improved impact resistance, RPC can be widely employed in piers of bridges, military construction and blast protection. There is no standard approach to assessing the impact resistance of concrete. This investigation utilises relatively well accepted impact equipment to evaluate the mechanical properties of RPC under dynamic loading. The compressive and flexural tensile strengths of plain and fibre reinforced RPC are investigated using a variety of specimens and apparatus. The dynamic increase factor (DIF) is evaluated to indicate the strain rate sensitivity of the compressive and flexural strength.
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Jaiswal, Lokendra. "Development and evaluation of permeable friction course mix design for Florida conditions." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0011900.
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Soutsos, Marios Nicou. "Mix design, workability heat evolution and strength development of high strength concrete." Thesis, University College London (University of London), 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308062.
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A literature survey of the properties and uses of high strength concrete, defined for this study as having a strength in excess of 60 N/tnm2, has shown that of prime need is a systematic, reproducible procedure for attaining high strength concrete. The "Maximum Density Theory", i.e. the requirement that the aggregate occupies as large a relative volume as possible, has been adopted as an approach to optimisation of the mix proportions. However, this does not consider the effect that the aggregate suIface area has on the requirement of excess paste for lubrication. To investigate the combined effect of void content and surface area, mixes with lower sand proportions than that required for minimum void content were tested for slump. The optimum sand proportion is the one that produces the highest slump, for a particular cement content. This procedure has been called: "The Modified Maximum Density Theory". Having thus optimised the cement and aggregate contents, partial cement replacement by mineral admixtures, at low water-cement ratios, has been investigated in order to assess: a) their contribution to long term strengths, b) their contribution to reducing the heat evolution of concrete mixes, and c) their effect on the workability of concrete. Condensed silica fume (at replacement levels of up to 15%) produced higher compressive strengths than ordinary Portland cement. Ground granulated blast furnace slag (at replacement levels of up to 30%) can be used without decreasing the 28-day strength. Replacement by 20% pulverised fuel ash resulted in a 15% decrease in the 28-day strength and equal strength to ordinary Portland cement concrete at ages beyond 56-days. Temperature measurements during hydration, under adiabatic conditions, have however shown that these replacement levels do not lower the temperature rise at a water-binder ratio of 0.26. The higher levels required for significant temperature reduction will also cause a significant reduction in the strength. To offset this ground granulated blast furnace slag (58%) and pulverised fuel ash (36%) in combination with 10% condensed silica fume 4 were used. These combinations reduced the temperature rise by more than 10°C while the reduction in the 28-day compressive strength was less than 15%. Partial cement replacement by pulverised fuel ash and ground granulated blast furnace slag improved the workability and therefore allowed a reduction in the superplasticiser dosage required for a given slump. The use of condensed silica fume reduces the workability at low superplasticiser dosages, but it has a water-reducing effect above a certain superplasticiser dosage. Results from these studies have been used to formulate guidelines for the proportioning of materials for producing high strength concrete.
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Eid, Mohd Nabil. "Proposal of a Mix Design Method for Low Cement Fiber Reinforced Concrete." Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/40586.
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Concrete, the second most used material in the world, presents great performance and economic benefits. Yet, it is often characterized by a brittle behaviour, low tensile strength, and toughness. Fibers are usually added to concrete to counteract its brittle behaviour, increasing ductility and toughness, controlling crack propagation and delaying concrete failure. However, their addition significantly worsens the fresh state performance of the material. To improve fresh state of the so-called Fiber Reinforced Concrete (FRC), conventional mix-design methods recommend the use of high paste content, which results in a significant increase of Portland cement (PC) content and raises the carbon footprint of the material. The latter is responsible for 8% of the global annual carbon dioxide (CO2) anthropogenic emissions. Given the current worldwide concerns on global warming, the construction industry is in a need to lessen the demand, and thus production of PC. Recent studies have been focusing on the use of advanced mix-design techniques (i.e. particle packing models- PPMs) along with Inert Fillers (IF) as an alternative to reduce PC content in concrete. However, the latter was not applied to conventional FRC. In this work, advanced mix design techniques (i.e. PPMs) are used to overcome the aforementioned issues and mix-proportion eco-efficient FRC with low cement content (< 300 kg/m3). Fresh (i.e. VeBe time, slump, rheological behaviour) and hardened (i.e. compressive strength, and flexural behaviour) state tests were performed on the proposed mixtures and compared with control high PC content (375 kg/m3) FRC mixes. Results show that PPM designed mixes presented higher minimum torque (yield stress) but quite comparable apparent viscositiy when compared to conventionally designed mixtures. Moreover, the flowability (i.e. VeBe time, and slump) tends to decrease as fiber content, length, and/or as the amount of fillers increase in the mixtures. In addition, PPM mixes exhibited a shear thinning behaviour following the Herschel-Bulkley model, which enables the design of FRC PPM mix-proportioned mixtures for applications requiring high torque regimes such as vibrated and/or pumped concrete. Finally, results show that the use of PPMs to mix proportion eco-efficient low cement FRC mixtures produced improved hardened (i.e. compressive strength, and flexural performance) state behaviour with lower environmental impact than conventional ACI designed FRC mixtures.
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Angelucci, Matteo. "The influence of mix design parameters and compressive strenght on durability indices." Master's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/9990.
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Includes abstract.Current concrete specifications used in mix design are mainly of the prescriptive type, i.e.recipe-based specifications that prescribe limiting values for certain mix design parameters such as minimum binder content, maximum water/binder (w/b) ratio and minimum compressive strength class. This has numerous economical, technical and environmental disadvantages and is one of the driving factors behind the development and promotion of performance-based specifications. These have the potential to lead to alternative methods of mix design to improve concrete structural performance. In South Africa, the use of the Durability Index Approach in performance-based specifications has grown increasingly. Durability can be thought of as a materials concept for a structure in a given environment for the duration of its design life. As such, it can only be accurately described by considering it as a function of numerous intrinsic and extrinsic interrelated factors. Despite this, a dominant assumption in the industry is that concrete durability is directly proportional to its binder content and compressive strength, largely due to the misinterpretation of prescriptive specifications in depicting factors like binder content as the governing parameter of durability. This results in uneconomical and often non-durable concretes due to implications of high cement contents, such as high costs (cement is the most expensive constituent of concrete), high shrinkage, thermal effects and alkali-silica reactions. This thesis presents a study on the influence of parameters of mix design, such as w/b ratio, binder content, binder type and curing regime, as well as compressive strength, on the durability of concrete as expressed by the Durability Index Approach. The objective of the investigation was to identify the issues behind specifications of minimum binder contents, as well as identify relationships between mix design parameters, compressive strength and durability indices. This was done by obtaining findings which would serve as a basis to potentially bring about sensible and justifiable changes to specifications. This could in turn lead to more durability-oriented mix design strategies. In order to verify whether prescriptive specifications such as minimum binder contents are justifiable, various studies in literature were reviewed on the subject. In the literature review, it was identified that certain relationships exist between aspects of concrete durability and various parameters, among which are binder content, w/b ratio and compressive strength. It was found that the nature of these relationships cannot be generalised as each relationship needs to take into consideration a variety of additional influencing factors. One example is that the influence of increasing binder content on durability indicators is often detrimental and can seldom be associated with beneficial effects. This is because there are other factors such as increasing paste volume that need to be considered.
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Pepe, Marco. "A conceptual model to design recycled aggregate concrete for structural applications." Doctoral thesis, Universita degli studi di Salerno, 2015. http://hdl.handle.net/10556/1956.
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2013 - 2014This thesis proposes a conceptual formulation for controlling the resulting mechanical properties of Recycled Aggregate Concretes (RACs) via generalised mix-design rules intended at covering the specific features of Recycled Concrete Aggregates (RCAs). As a matter of fact, the RCAs are characterised by a higher porosity and water absorption capacity than ordinary aggregates and, hence, general mix-design rules for ordinary structural concrete cannot be applied to RACs as such. Therefore, as a further step that goes beyond the currently available experimental and empirical investigations, the research presented in the present thesis proposes a rational mix design method for predicting the compressive strength evolution of RACs by considering both the mixture composition and the key properties of RCAs (i.e.; the amount of the attached mortar and indirectly the water absorption capacity). The formulations proposed in this thesis are based upon the results of several investigations carried out for characterising both RCAs and RACs. In fact, several tests were performed on different kinds of recycled aggregates, taking into account their origin, the processing procedure adopted for crushing the concrete demolition debris and their resulting size grading. The analysis of the results obtained in these tests led to proposing a comprehensive conceptual formulation that links the main engineering properties of aggregates to the porosity, particle density and attached mortar content of RCAs. Moreover, several concrete batches were produced for investigating the influence that three key parameters (viz. aggregate replacement ratio, nominal water-to-cement ratio and initial moisture condition of aggregates) have on the relevant properties for structural concrete. The behaviour of structural concrete is then analysed at a “fundamental” level, with the aim of scrutinising the physical properties and the mechanical behaviour of RACs, by taking into account the actual mixtures composition. Particularly, it is based on observing the hydration process developing inside RACs during the setting and hardening phase, and how these are influenced by the presence of RCAs. The activities described in this work were carried out at the laboratories of the University of Salerno (IT), the Federal University of Rio de Janeiro (BR), as part of the “EnCoRe” Project (FP7- PEOPLE-2011-IRSES n. 295283; www.encorefp7.unisa.it) funded by the European Union within the Seventh Framework Programme, and Delft University of Technology (NL). [edited by Author]
XIII n.s.
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Reinert, Sybil K. "Optimizing Portland cement concrete mix design to environmental and construction variables with the aid of computer design software." [Ames, Iowa : Iowa State University], 2007.
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Buchberg, Brandon S. "Investigation of mix design and properties of high-strength/high-performance lightweight concrete." Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/23394.
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Bai, Jiping. "Durability, service life estimation and mix design of concrete using an expert system." Thesis, University of Dundee, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288452.
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Buidens, Daniel Aaron. "Effects of Mix Design Using Chloride-Based Accelerator on Concrete Pavement Cracking Potential." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5411.
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Cracked pavement slabs lead to uncomfortable and eventual unsafe driving conditions for motorists. Replacement of cracked pavement slabs can interrupt traffic flow in the form of lane closures. In Florida, the traffic demands are high and pavement repairs need to be carried out swiftly typically using concrete with high cement contents and accelerators to create rapid setting and strength gain. The concrete used in these pavement replacements is usually accompanied by a high temperature rise, making the replaced slabs susceptible to cracking. Cracking is a result of developed tensile stresses in the concrete, which exceed the concrete's tensile strength capacity. This research is being conducted to determine the risk of cracking for pavement slabs with varying dosages of chloride based accelerator used to promote high early strength. To analyze the effect of the accelerator, five different concrete mixtures including a control were assessed in a series of tests with varying accelerator dosages. Experiments included: mortar cube testing, concrete cylinder testing, autogenous deformation measured with a free-shrinkage frame, and restrained stress analysis using a rigid cracking frame.
The findings indicate that accelerators are necessary to meet the strength requirements, and that the higher the accelerator dose, the higher the early shrinkage in the first 24 hours determined from the free shrinkage frame. Accidental overdose of the chloride-based accelerator results in the highest cracking potential and the highest shrinkage when tested under field generated temperature profiles.
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Meroni, Fabrizio Luigi. "Optimizing the Use of Reclaimed Asphalt Pavement (RAP) in Hot Mix Asphalt Surface Mixes." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/101865.
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The most common use of reclaimed asphalt pavement (RAP) is in the lower layers of a pavement structure, where it has been proven as a valid substitute for virgin materials. Instead, the use of RAP in surface mixes is more limited, with a major concern being that the high RAP mixes may not perform as well as traditional mixes. To reduce risks of compromised performance, the use of RAP has commonly been controlled by specifications that limit the allowed amount of recycled material in the mixes. However, significant cost and environmental savings can be achieved if more RAP is included in the surface layer. This dissertation develops an approach that can be followed to incorporate more RAP in the surface mix while maintaining good performance. The approach is based on the results from three studies that looked at how to optimize the design of the mix, in terms of rutting and fatigue resistance, when more RAP is used.
In the first study, a high RAP control mix and an optimized mix designed using different design compaction energy (65 and 50 gyrations respectively) were compared. The optimization process consisted in the definition of an alternative mix composition that supported the higher binder content allowed by the lower design compaction energy. Using Accelerated Pavement Testing and laboratory characterization it was possible to assess the potential of mix optimization with the objective of improving rutting resistance. The testing showed no indication that the optimized mixes would have rutting problems, supporting the implementation of the reduction of the design compaction energy level. The optimized mix exhibited a similar or superior rutting resistance in the full-scale setting, in the laboratory, and in the forensic investigation.
The second part focused on the production of highly recycled surface mixes capable of performing well. To produce the mixes, a balanced mix design (BMD) methodology was used and a comparison with traditional mixes, prepared in accordance with the requirements of the Virginia Department of Transportation (VDOT) volumetric mix design, was performed. Through the BMD procedure, which featured the indirect tensile cracking test for evaluating the cracking resistance and the Asphalt Pavement Analyzer for evaluating rutting resistance, it was possible to optimize the selection of the optimum asphalt content. Also, it was possible to obtain a highly recycled mix (45% RAP) capable of achieving better overall performances than traditional mixes while carrying a large reduction in production cost.
The final part evaluated the laboratory performance of four different highly recycled surface mixes to support their possible implementation in the state of Virginia. The mixes featured either 30% or 45% RAP, different asphalt contents, the use of a WMA additive, and a rejuvenator. To analyze the mixes' performance in great depth, a three-level (base, intermediate, and advanced) testing framework was defined. Each level was characterized by an increasing degree of complexity and included tests to characterize both the cracking resistance and the rutting resistance. The study aimed at investigating the features of the various laboratory tests. Through the review of the theoretical background, the evaluation of the test procedures, and statistical analysis of the results, it was possible to identify the strengths and weaknesses of each test and to provide guidelines to develop appropriate quality assessment criteria and mix design methodology.
In summary, throughout this research, it was possible to observe that the respect of Superpave mix design requirements alone, with particular reference to gradation limits and volumetric properties, was not guarantee of satisfactory performance in terms of both cracking and rutting resistance. To increase the confidence in the RAP properties, increase the current recycling levels, and introduce more appropriate mix design specifications, BMD could be used (even with simple laboratory tests) to check performance-based criteria.Doctor of Philosophy
Nowadays, transportation agencies are expected to perform a large number of pavement rehabilitation projects, while facing major limitations in budgetary funds. In order to have safe, efficient, and cost-effective roadways, the economic advantage of recycling is boosting an effort to increase the amount of RAP in asphalt mixtures. In addition, over the past decades, the environmental awareness of the transportation agencies and public increased significantly, pushing even more towards the use of new green technologies. The use of RAP became noticeable in the 1970s and its popularity increased significantly since that time. However, there are still many open questions which prevent larger uses of recycled materials, mainly related to the design methodology and the field performances of recycled mixtures. Therefore, today there is a large untapped potential that would grow even more the magnitude of pavement recycling and of the associated benefits. New design procedures, based on the support of laboratory tests to characterize the mixtures, and full-scale experiments are the tools that pavement engineers can use in order to enrich the knowledge of highly recycled road materials and grow the confidence of public agencies and contractors towards these new more sustainable solutions. Throughout this dissertation it was possible to evaluate new innovative ways of incorporating more RAP in the asphalt mixtures through the analysis of current state of the art and the proposition of new procedures.
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Dall'Olio, Enrico. "Ottimizzazione di mix design di geopolimeri a base di metacaolino e studio dei relativi processi di formatura." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/11268/.
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Il seguente lavoro di tesi si pone come obiettivo di ottimizzare il mix design di materiali geopolimerici a base di metacaolino in modo da ottimizzare il procedimento di formatura tramite pressatura tipico delle piastrelle ceramiche.
La parte iniziale del lavoro sperimentale è stata incentrata sullo studio dell’ottimizzazione delle formulazioni per ottenere impasti geopolimerici a base di metacaolino idonei per la pressatura e il colaggio; sono stati quindi preparate diverse formulazioni ottenute variando diversi parametri di processo, quali il contenuto totale di acqua dell’impasto e la concentrazione di quarzo utilizzato come filler inerte.
Su tali mix è stato individuato il processo di formatura più idoneo dal punto di vista di temperatura di consolidamento, modalità e tempi di cottura ed è stato messo a punto il procedimento ottimale per la preparazione dei materiali, procedimento che è stato poi mantenuto per l’intero decorso dello studio. Nella produzione degli impasti si è deciso di eliminare sistematicamente quelle formulazioni che avevano prodotto materiali con peggiori prestazioni fisiche, come alcune formulazioni testate per il colaggio.
Successivamente, dopo avere preparato i campioni, su di essi sono state eseguite le prove di assorbimento d’acqua e porosimetria ad intrusione di mercurio, per valutare le caratteristiche fisiche dei vari impasti prodotti, osservazioni al microscopio ottico e al microscopio a scansione elettronica, per analizzare i campioni selezionati dal punto di vista microstrutturale e morfologico e prove al microscopio riscaldante, per studiarne il comportamento alle alte temperature.
I risultati ottenuti sono stati messi a confronto con quelli dei materiali ceramici tradizionali, per avere indicazioni sulla potenzialità dei prodotti a base geopolimerica come alternativa alla produzione di piastrelle ceramiche.
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Babalola, O. E., P. O. Awoyera, M. T. Tran, D. H. Le, O. B. Olalusi, A. Viloria, and D. Ovallos-Gazabon. "Mechanical and durability properties of recycled aggregate concrete with ternary binder system and optimized mix proportion." Elsevier Editora Ltda, 2020. http://hdl.handle.net/10757/656774.
Full textAbstract:
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.This study aimed to investigate the mechanical and durability properties of recycled aggre-gate concrete with a ternary binder system and optimized mix proportion. Two concretebatches were developed using a densified mix design approach (DMDA) to evaluate therequired mix proportions. Batch I have GGBS content varied at 0%, 10%, 20%, 30%, 40% and50% at constant w/b ratio of 0.45, while batch II concrete mix have varied water/binder ratios:0.3, 0.35, 0.4, 0.45 and 0.5 at constant GGBS replacement level of 30%. The fine aggregate(river sand) of the two batches was blended with fly ash at optimum loose packing density(FA + Sand) and superplasticizer (SP) was incorporated in the mix at a constant level of 1.4%.A control mix comprising of natural aggregate was also developed. The results obtainedshowcased the feasibility of producing structural concrete with recycled aggregates usingGGBS and fly ash. The mechanical and durability properties were best at 30% GGBS contentand 0.35 water/binder ratio. The DMDA for mix proportion adopted for RAC contributed sig-nificantly to improving its properties when compared to NAC, especially at the optimumobserved RAC mix with compressive strength of 52 MPa. Also, the mix demonstrated goodpermeability resistance in terms of chloride-ion ingress and capillary water absorption.
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PATEL, PRERNA D. "DESIGN OF A PIXEL SCALE OPTICAL POWER METER SUITABLE FOR INCORPORATION IN A MULTI-TECHNOLOGY FPGA." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1066421274.
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Ji, Su Jian. "Investigation of factors affecting resilient modulus for hot mix asphalt." Thesis, University of Canterbury. Civil Engineering, 2006. http://hdl.handle.net/10092/1083.
Full textAbstract:
Resilient modulus is an important property for asphalt concrete design and for mechanistic analysis of pavement response under traffic loading. This study investigates the different factors affecting the resilient modulus of hot mix asphalt. A fractional factorial design of experiment was carried out to investigate six factors each factor was studied at two levels. These factors are: the maximum nominal aggregate size, specimen diameter and thickness, the load pulse form and duration, and the compaction method. Two types of hot mix asphalts with different maximum aggregate sizes (10 mm and 14 mm) were studied. Gyratory and Marshall compaction methods were used to prepare the specimens. Sinusoidal and triangular load pulse forms were used in the measurement of the resilient modulus. This study attempts to examine how the different factors interrelate to affect the resilient modulus. In addition to this, two other investigations will be carried out. The first is the comparison of the strain backcalculated using the resilient modulus test results with the strain measured using strain gages and strain values obtained from finite element modelling (FEM), and determine whether the FEM or the closed form equation is the more accurate method for determining strain. The second is the investigation of the relationship between the flexural, complex and resilient modulus. Analysis of the factorial experimental design showed that the maximum nominal aggregate size is the most important factor affecting the resilient modulus, followed by the load duration, the specimen geometry represented by the thickness and diameter then the interactions between the different factors. The strain comparison suggested that the closed form equations were indeed a suitable approach to determine maximum horizontal strain during a resilient modulus test. The modulus comparison suggested that it is possible to predict either resilient, complex and flexural modulus given that only one of them is known, but only for AC10 specimens.
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Camplese, Mariangela. "Studio di conglomerati bituminosi drenanti contenenti polverino di gomma da Pneumatici Fuori Uso (PFU)." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016.
Find full textAbstract:
Gli odierni sviluppi delle reti stradali nel territorio italiano e l’aumento della propensione all’utilizzo del veicolo hanno portato ad una continua ricerca nello stesso ambito volta sì a mantenere alti i livelli prestazionali e di sicurezza sulla rete stradale ma anche ad aprirsi ad uno scenario ecosostenibile, dato il continuo scarseggiare di materie prime per proseguire con le usuali tecniche di produzione.
In tutti i campi riguardanti l’ambito delle costruzioni civili, che siano esse strutturali o infrastrutturali, numerose sono state le tecnologie introdotte per la realizzazione di materiali sostenibili ma anche e soprattutto il recupero di materiale di scarto, andando così incontro oltre che a una costruzione sostenibile anche ad un recupero di ciò che sarebbe destinato a discariche, ufficiali o abusive che siano.
Nell’ottica dell’introduzione di “nuovi” materiali una posizione di rispetto interessa gli Pneumatici Fuori Uso (PFU) il cui recupero sotto forma di granulato e di polverino in gomma costituiscono, nell’ambito delle pavimentazioni stradali, una notevole opportunità di riutilizzo all’interno dei conglomerati bituminosi.
Il presente lavoro sperimentale è stato svolto nell’ottica di analizzare dapprima le caratteristiche delle pavimentazioni drenanti, del polverino di gomma da PFU e dell’interazione tra i due, a supporto delle sperimentazioni effettuate sulle miscele realizzate in laboratorio. In particolare, sfruttando la tecnologia dry, che permette l’inserimento del polverino nella fase di miscelazione degli aggregati, dopo un’attenta analisi preliminare della composizione delle miscele da realizzare e il successivo confezionamento dei provini e loro addensamento, si è proceduto all’esecuzione di diverse prove al termine delle quali sono state analizzate le differenze meccaniche e reologiche tra miscele ottenute con aggiunta di polverino e miscele prive di PFU.
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BJÖRKGREN, SANDRA, and NORDIN ANNA SILFVERSTEN. "Hur utformar vi en hållbar affärsplan?" Thesis, Högskolan i Borås, Institutionen Textilhögskolan, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-20126.
Full textAbstract:
Syftet med uppsatsen är att skapa en affärsplan och utveckla vår affärsidé som från början var att sälja herrkläder i ett lägre prissegment till killar mellan 18-30 år på den svenska marknaden. Våra problemformuleringar är; Hur utformar vi en hållbar affärsplan? Hur skapar vi en affärsidé för vårt valda koncept? Hur ska erbjudandet utformas och vilka delar bör ingå för att nå potentiella konsumenter?Vi har studerat olika källor där exempel på affärsplaner och vad de innehåller tagits upp, vi har även genom personliga möten på Drivhuset i Borås fått hjälp av projektledaren Linn Johansson att utveckla vårt koncept och affärsplan. Genom en marknadsundersökning där vi tillfrågade killar mellan 18-30 år så ville vi ta reda på vilken som är vår målgrupp och även se om det finns intresse får vårt koncept. Undersökningen gav oss en bra grund att bygga vidare vår affärsplan och affärsidé på. I vår affärsplan har vi valt att koncentrera oss på affärsidén, visioner och mål, marknadsplan och risker. I marknadsplanen bestämmer vi vår marknad genom segmentering och positionering. Vi tittar på konkurrensbilden genom SWOT-analyser och en omvärldsanalys. Vi presenterar marknadsmixen och hur vi valt att använda oss av den för att nå ut på marknaden och vilka delar som vi tycker är viktigast för oss. Vi har i uppsatsen analyserat vår tänkta kund, marknad och konkurrenter genom olika metoder. Exempelvis har vi gjort SWOT-analys på vår affärsidé och även på de två största konkurrenterna som vi fick fram genom marknadsundersökningen, Jack & Jones och Carlings. Genom Porters femkraftsmodell har vi också analyserat andra tänkbara faktorer som kan påverka oss än de faktorer som tar upp den befintliga situationen på marknaden. I slutet av vår affärsplan har vi presenterat tre tänkbara riskscenarier där vi tar upp det bästa som kan hända(bästa fallet), det värsta som kan hända(sämsta fallet), det som troligtvis kan inträffa(normalfallet), riskerna med dem samt hur vi skall kunna åtgärda dem.The purpose of this paper is to create a business plan and develop our business concept that was originally selling men's clothing at a lower price segments for men between 18-30 years in the Swedish market. Our problem formulation is: How do we design a sustainable business plan? How do we create a business concept for our selected concept? How should the offer be designed and what elements should be included to reach potential consumers? We have studied different sources with examples of business plans and what they contains, we have also through personal meetings at Drivhuset in Borås been assisted by the Project Manager Linn Johansson to develop our concept and business plan. In a survey did we interview men between 18-30, because we wanted to find out which one is our target audience and also see if there is interest for our concept. The study gave us a good foundation to build our business plan and business concept on. In our business plan we have chosen to concentrate on the business concept, vision and objectives, marketing plan and risks. In the market plan we will determine our market through segmentation and positioning. We look at the competitive landscape through SWOT analysis and business intelligence. We present the marketing mix and how we chose to make use of it to reach the market and which parts we think are most important to us. In our essay we have analyzed our prospective customer, market and competitors through various methods. For example, we have SWOT analysis of our business and also on the two largest competitors as we got up by the market investigation, Jack & Jones and Carlings. By Porters five forces we have also analyzed other potential factors that may affect us than the factors that reflects the current market situation. I the end of our business plan, we have presented three possible risk scenarios in which we take up the best thing that can happen (best case) and, the worst that could happen (worst case), it is as likely to occur (typically), the risk associated with them, and how we to remedy them.
Program: Butikschefsutbildningen
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Padula, Martin. "Automation of the Superpave mix design process for the West Virginia Division of Highways." Morgantown, W. Va. : [West Virginia University Libraries], 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2678.
Full textAbstract:
Thesis (M.S.)--West Virginia University, 2002.Title from document title page. Document formatted into pages; contains ix, 145 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 63-65).
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Peng, Kun. "Analysis and Design of Secure Sealed-Bid Auction." Thesis, Queensland University of Technology, 2004. https://eprints.qut.edu.au/15848/1/Kun_Peng_Thesis.pdf.
Full textAbstract:
Auctions have a long history and are an effective method to distributed resources. In the era of Internet and e-commerce, electronic sealed-bid auction play an important role in business. However, it is a risk to run a sealed-bid auction through the Internet, which is an open and unreliable environment. There are many security concerns about correctness and fairness of the auction and privacy of the bidders in electronic sealed-bid auctions. Cryptology seems to be the only security solution for electronic sealed-bid auction. On the other hand, a practical electronic sealed-bid auction scheme must be efficient. So efficient application of cryptographic tools to electronic sealed-bid auction is the focus of this thesis. Firstly, security requirements of sealed-bid auctions are surveyed. The auction result must be determined correctly according to the submitted bids and the pre-defined auction rule. The bidders must compete with each other in a fair play and none of them can take advantage of others. The auction must be publicly verifiable, so that the auction result is acceptable by everyone. Usually, a losing bidder hopes to keep his bid secret, so the losing bids should be kept secret. In different applications, different auction rules may be applied. So, to avoid a tie, a large number of biddable prices must be accepted in some applications. Secondly, the currently known sealed-bid auction schemes are classified. In recent years, many sealed-bid auction schemes based on various cryptographic primitives have been proposed. Nearly all of them can be classified into five models. In the Model 1, each bid is known to the auctioneers, who can find the winning bid and winner very efficiently. Bid privacy is not implemented in Model 1. In Model 2 homomorphic bid opening is employed, so that the winning bid and winner can be found while the losing bids are kept secret. In Model 3 very strong bid privacy is achieved through a Dutch-style bid opening, which is highly inefficient. In Model 4, the link between the bids and bidders instead of confidentiality of the bids is kept secret. This kind of confidentiality is weaker than normal bid privacy and called relative bid privacy in this thesis. (Complete confidentiality of the bids in the end of the auction is called absolute bid privacy.) Implementation of relative bid privacy can be very efficient if an efficient anonymous channel can be constructed. Model 5 uses secure evaluation to open the bids and find the auction result and makes it possible to achieve absolute bid privacy efficiently. Three main cryptographic primitives are explored and employed to design new auction schemes in four auction models. The first tool is batch verification, which can improve computational efficiency in auction schemes. The second is mix network, which can be used to implement anonymous channels in Model 4 and Model 5. Two new efficient mix networks are designed and used in Model 2, Model 4 and Model 5. The third is secure evaluation, which is employed in two new auction schemes in Model 5 to achieve strong bid privacy efficiently. Other cryptographic primitives employed in the auction schemes include efficient 1-out-of-w oblivious transfer in Model 2 and key chain in Model 3. Five new auction schemes are proposed. The first scheme in Model 2 batch verifies bid validity to improve efficiency. The second scheme optimises the key chain used in Model 3 to obtain a more advanced auction scheme. The third scheme implements a concrete anonymous channel in Model 4 for the first time and achieves relative bid privacy and high efficiency convincingly. The last two employ new secure evaluation techniques to achieve absolute bid privacy and high efficiency. With these five new auction schemes, better solutions are achieved in various auction applications.
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Peng, Kun. "Analysis and Design of Secure Sealed-Bid Auction." Queensland University of Technology, 2004. http://eprints.qut.edu.au/15848/.
Full textAbstract:
Auctions have a long history and are an effective method to distributed resources. In the era of Internet and e-commerce, electronic sealed-bid auction play an important role in business. However, it is a risk to run a sealed-bid auction through the Internet, which is an open and unreliable environment. There are many security concerns about correctness and fairness of the auction and privacy of the bidders in electronic sealed-bid auctions. Cryptology seems to be the only security solution for electronic sealed-bid auction. On the other hand, a practical electronic sealed-bid auction scheme must be efficient. So efficient application of cryptographic tools to electronic sealed-bid auction is the focus of this thesis. Firstly, security requirements of sealed-bid auctions are surveyed. The auction result must be determined correctly according to the submitted bids and the pre-defined auction rule. The bidders must compete with each other in a fair play and none of them can take advantage of others. The auction must be publicly verifiable, so that the auction result is acceptable by everyone. Usually, a losing bidder hopes to keep his bid secret, so the losing bids should be kept secret. In different applications, different auction rules may be applied. So, to avoid a tie, a large number of biddable prices must be accepted in some applications. Secondly, the currently known sealed-bid auction schemes are classified. In recent years, many sealed-bid auction schemes based on various cryptographic primitives have been proposed. Nearly all of them can be classified into five models. In the Model 1, each bid is known to the auctioneers, who can find the winning bid and winner very efficiently. Bid privacy is not implemented in Model 1. In Model 2 homomorphic bid opening is employed, so that the winning bid and winner can be found while the losing bids are kept secret. In Model 3 very strong bid privacy is achieved through a Dutch-style bid opening, which is highly inefficient. In Model 4, the link between the bids and bidders instead of confidentiality of the bids is kept secret. This kind of confidentiality is weaker than normal bid privacy and called relative bid privacy in this thesis. (Complete confidentiality of the bids in the end of the auction is called absolute bid privacy.) Implementation of relative bid privacy can be very efficient if an efficient anonymous channel can be constructed. Model 5 uses secure evaluation to open the bids and find the auction result and makes it possible to achieve absolute bid privacy efficiently. Three main cryptographic primitives are explored and employed to design new auction schemes in four auction models. The first tool is batch verification, which can improve computational efficiency in auction schemes. The second is mix network, which can be used to implement anonymous channels in Model 4 and Model 5. Two new efficient mix networks are designed and used in Model 2, Model 4 and Model 5. The third is secure evaluation, which is employed in two new auction schemes in Model 5 to achieve strong bid privacy efficiently. Other cryptographic primitives employed in the auction schemes include efficient 1-out-of-w oblivious transfer in Model 2 and key chain in Model 3. Five new auction schemes are proposed. The first scheme in Model 2 batch verifies bid validity to improve efficiency. The second scheme optimises the key chain used in Model 3 to obtain a more advanced auction scheme. The third scheme implements a concrete anonymous channel in Model 4 for the first time and achieves relative bid privacy and high efficiency convincingly. The last two employ new secure evaluation techniques to achieve absolute bid privacy and high efficiency. With these five new auction schemes, better solutions are achieved in various auction applications.
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Namutebi, May. "An investigation into some aspects for foamed bitumen technology." Doctoral thesis, KTH, Byggvetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-193916.
Full textAbstract:
Despite applications of foamed bitumen technology in pavement construction in various places around the world, there are still several aspects about this technology that are not clear. In addition, knowledge on foamed bitumen technology is mainly empirical and lacks scientific basis. This study addresses some of the aspects for foamed bitumen technology such as: Investigation of any effects in binder composition during the production process for foamed bitumen; assessment of the effect of bitumen source on foamed bitumen characteristics; development of a rational method to optimise foamed bitumen characteristics and conditions; evaluation of aggregate particle coating within foamed bitumen mixes; further improvements in the mix design procedure specifically the method of compaction and optimum bitumen content determination stages are suggested. Fourier transform infrared spectroscopy techniques were used to investigate any changes in bitumen composition after the production process of foamed bitumen. Fourier transform infrared tests were done on foamed bitumen and neat bitumen specimens for two bitumens with similar penetration grades. Foamed bitumen characteristics of three bitumens were established by producing foamed bitumen at temperatures of 150ºC up to 180ºC and foamant water contents of 1, 2, 3, 4 and 5%. From the analysis of variation of foamed bitumen characteristics (maximum expansion ratio and half-life) at different temperatures a new method based on the equi-viscous bitumen temperature to optimize foamed bitumen conditions and characteristics was proposed. Rice density and surface energy concepts were used to evaluate aggregate particle coating with foamed bitumen. A granite aggregate divided into three different size fractions and three sets of foamed bitumen produced from three bitumen penetration grades were used. A gyratory laboratory compaction procedure for laterite gravels treated with foamed bitumen was established using the modified locking concept. Three laterite gravels with different chemical composition were mixed with foamed bitumen produced from one penetration bitumen grade. The resulting mixes were compacted up to 200 gyrations and the corresponding compaction curve defined in terms of height versus number of gyrations noted. In addition, the optimum moisture content requirements at the modified locking point were determined. 3D packing theory concepts, primary aggregate structure porosity and an indirect tensile strength criteria were employed to determine optimum bitumen content for foamed bitumen mixes. Fourier infrared techniques revealed that foaming did not cause any changes in the bitumen chemistry, implying that the foamed bitumen production process may possibly be a physical process. Characterisation of foamed bitumen produced from three bitumen penetration grades showed that foamed bitumen characteristics (maximum expansion ratio and half-life) were mainly influenced by binder viscosity rather than the source. The equi-viscous temperature seemed to provide a suitable criterion at which foamed bitumen with optimum characteristics could be produced. Rice density results showed that aggregate size fraction, binder expansion ratio and viscosity influenced aggregate particle coating. For the coarser aggregate fraction, results revealed that binder coating seemed to be mainly influenced by temperature. Whilst for fine aggregate fraction the coating was mainly influenced by surface area. Surface energy results revealed that foamed bitumen exhibited better coating attributes than neat bitumen. A new laboratory compaction procedure for laterite gravels treated with foamed bitumen based on the modified locking point was developed. The modified locking point represents the state at which maximum aggregate particle interlock occurs when mixes are compacted in the field. It is based on the iii analysis of the rate of change for the gyratory compaction curve. The compaction curve in this case is defined in terms of compaction height versus number of gyrations. Gradation analysis beyond the modified locking point showed that aggregate particle breakdown occurred. Analysis of the optimum moisture at the modified locking point revealed that the moisture conditions were less than the aggregate optimum moisture conditions. It is recommended that this point be used to determine the optimal compaction characteristics of foamed bitumen mixes. Aggregate structure porosity and an indirect tensile strength criteria can be used to determine the bitumen content that could be used in design of foamed bitumen mixes. This would reduce the amount of resources required since the bitumen content could be estimated prior to carrying out the actual laboratory work given that the aggregate grading is known. The aggregate structure can be divided (based on 3D packing theory) into oversize, primary, and secondary structures. The primary structure is mostly responsible for carrying loads whilst the secondary structure fills the voids within the primary structure and provides support to the primary structure. The aggregate size particles constituting the primary structure are deduced as a function of standard sieve sizes using the packing theory concepts. The minimum sieve size for the primary structure is proposed as 1 mm. The oversize structure consists of aggregate particles whose size is greater than the maximum size for the primary structure. The secondary structure consists of aggregate particles whose size is below the minimum size for the primary structure. The primary aggregate structure porosity can be used to establish the starting bitumen content; the bitumen content at which this porosity is 50% is chosen as the initial bitumen content. Indirect tensile strength values corresponding to 50% primary porosity are determined as well as the bitumen contents and compared against the recommended minimum values.QC 20161012
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Gates, Matthew David 1973. "Lean manufacturing system design and value stream management in a high-mix, low-volume environment." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/34746.
Full textAbstract:
Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering; in conjunction with the Leaders for Manufacturing Program at MIT, 2004.Includes bibliographical references (p. 156).
Value Stream Mapping is a powerful tool for identifying sources of waste and for creating the vision for the future state of a production system. As a management tool, however, it lacks in specific focus of roles, responsibilities, and actions required to achieve the future state vision. The limitations become more evident and the problems of execution become exacerbated when multiple value stream projects are launched with limited human resources available. This thesis describes a set of management tools to complement Value Stream Mapping. The tools are expected to improve management visibility and accountability. The design of a lean production system is also proposed in this thesis. The lean production system includes a newly designed layout for the manufacturing cell as well as the "operating system" for the cell. The layout is based on the principles of cellular manufacturing in order to promote flow and improve quality. The operating system includes such things as production batch sizes, product routings, and strategic inventory locations. Based on the future state value stream map and supported by a discrete-event simulation, the new operating system is designed to align the lean strategy with the technical capabilities of the manufacturing line. As confirmed by the simulation, implementation of the new production system is expected to reduce lead time for the cell by 2/3, realize a corresponding one-time reduction in inventory of $350,000, and increase on-time delivery of the cell to over 97%. In total, the project has a three-year net present value exceeding a quarter of a million dollars.
by Matthew David Gates.
S.M.
M.B.A.
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Jenkins, Kim Jonathan. "Mix design considerations for cold and half-warm bituminous mixes with emphasis of foamed bitumen." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51831.
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Dissertation (PhD)--University of Stellenbosch, 2000.ENGLISH ABSTRACT: The use of foamed bitumen and bitumen emulsion as binders for use in road rehabilitation is gaining favour globally. High-level road facilities through to unpaved roads requiring attention are being treated with these binders due to environmental, economic and practical benefits in the use of cold bituminous mixes. In addition, static and mobile plant with the capability of performing stabilisation using bitumenemulsion and foamed bitumen has become commercially available and widely utilised, as a result of development in recycling technology and lapse in patent rights on foam nozzles. An understanding of the behaviour and failure mechanisms of these cold mixes, as well as sound guidelines for the mix design procedures of cold mixes, especially foamed bitumen, and design guidelines for pavements structures incorporating these materials, are lacking however. Mix designs are carried out primarily on the basis of experience and pavement designs are empirically based. The main objective of this dissertation is to address the need for a fundamental understanding of foamed bitumen and foamed bitumen mixes, and in so doing to develop techniques for adjudicating mixes, optimising their composition and rationalising their design both as mixes and as layers in road pavements. At the same time the exploration of new applications for foamed bitumen and the possibilities for progressive related technology, is a priority. To commence, this study includes an appraisal of most of the literature available on foamed bitumen. This is followed by a fundamental investigation of the colloidal mass of foam that is produced when small quantities of cold water are added to hot bitumen. Factors influencing the quality of the foam are identified and a Foam Index is developed for characterisation and optimisation of the foam. The spatial composition of a cold foamed bitumen mix, including Interaction of the foam with moist mineral aggregate, is also addressed in this dissertation. In particular, the stiffening of the filler mastic using foamed bitumen as binder is analysed. Techniques of optimising the sand type and content in the mix are also developed and guidelines for desired aggregate structures for foam treatment are established. The temperature of the mineral aggregate has been shown to have a profound influence on the behaviour and performance of a foamed bitumen mix. This has been selected as a focal area of further investigation and the research has lead to the development of a new process called "The half-warm foamed bitumen treatment process" that can produce mixes with almost the quality of hot mix asphalt with up to 40% less energy consumption. Other processes developed in this research include the use of cold mix asphaltic blocks for construction of road pavements in developing areas. This technology enhances the use of a high labour component in road construction in an economically competitive manner. The dissertation provides details for mix design and construction of the cold mix blocks. Finally, the study includes models for the performance prediction of foamed bitumen mixes. In particular, foamed mixes that exhibit stress-dependent behaviour have been investigated and models established on the basis of triaxial testing and accelerated pavement testing for the prediction of permanent deformation of such layers under repeated loading. Practical applications of the research findings are summarised in Appendix F. This includes: • methods for optimisation of the foamed bitumen properties, • guidelines for the selection of the ideal aggregate structure for cold foamed mixes, • procedures for carrying out cold mix design in the laboratory (including mixing, compaction and curing), • procedures for manufacturing half-warm foamed mixes in the laboratory, • methods for manufacturing cold mix blocks, and • pavement design methods for road structures incorporating foamed mix layers. Appendix G outlines statistical techniques that are relevant to the design of experiments in pavement engineering including examples of applications of these procedures. The techniques are applied selectively in the relevant chapters of the dissertation.
AFRIKAANSE OPSOMMING: Die gebruik van skuim bitumen en bitumen emulsie as bindmidel in pad rehabilitasie begin groter voorkeur wêreldwyd geniet. Van hoë vlak padfasiliteite tot ongeplaveide paaie wat aandag benodig, word met hierdie binders behandel vanweë die omgewings-, ekonomiese en praktiese voordele wat hierdie koue bitumen mengsels inhou. Voorts is statiese en mobiele masjinerie wat die vermoë het om stabilisasie in die gebruik van bitumenemulsie en skuimbitumen te bewerkstellig, in die handel verkrygbaar. Dit word algemeen gebruik as 'n uitvloeisel van ontwikkelings in herwinningstegnologie en die verslapping van patenteregte op skuim sproeikoppe. 'n Leemte bestaan in die begrip van die gedrags- en swigtingsmeganismes van hierdie koue mengsels, asook goeie riglyne vir die mengselontwerp van koue mengsels en in besonder skuimbitumen, en ontwerpriglyne vir plaveisel strukture waar hierdie materiaal geinkorporeer is. Mengselontwerpe word hoofsaaklik uitgevoer op grond van ondervinding, terwyl plaveiselontwerpe empiries gebaseer is. Die hoofdoel van die verhandeling is om die behoefte vir 'n fundamentele begrip van skuim bitumen en skuimbitumen mengsels aan te spreek, en daardeur tegnieke te ontwikkel vir die be-oordeling van mengsels, optimsering van hul samestelling en rasionalisering van hulontwerp vir beide mengsels en plaveisellae. Terselfdertyd is die ondersoek na nuwe toepassings van skuim bitumen en die moontlikhede van nuwe tegnologie 'n prioriteit. As beginpunt sluit hierdie studie 'n waardeskatting van die meeste literatuur beskikbaar op skuim bitumen in. Dit word gevolg deur 'n basiese ondersoek na die kolloidale massa van skuim wat geproduseer word wanneer klein hoeveelhede koue water by warm bitumen gevoeg word. Faktore wat die gehalte van die skuim beinvloed word uitgewys en 'n Skuim Indeks is ontwikkel vir die karakterisering en optimisering van die skuim. Die ruimtelike samestelling van 'n koue bitumen mengsel, wat die interaksie van die skuim met vogtige minerale samevoegings (aggregate) insluit, word ook aangespreek. Besondere aandag word gewy aan die verharding van die vuiler mastiekgom wat gebruik word as bitumen binder. Tegnieke om die sandtipe en inhoud van die mengsel te optimiseer is ontwikkel en riglyne vir die verlangde samevoegingstrukture (aggregate strukture) vir skuimbehandeling is opgestel. Daar is bevind dat die temperatuur van die minerale aggregaat 'n duidelike invloed op die gedrag en verrigting van 'n skuimbitumen mengsel het. Dit is gekies as In fokuspunt vir verdere studie en die navorsingswerk daarop het gelei tot die ontwikkeling van In nuwe proses wat "Die half-warm skuim bitumen behandelings proses" genoem word. Hierdie proses produseer mengsels wat byna gelykstaande is aan die gehalte van warm gemengde asfalt, maar met tot 40% minder energie verbruik. Ander prosesse wat met dié navorsing ontwikkel is, sluit koue gemengde asfaltiese blokke in, wat gebruik word in die konstruksie van padplaveisel in ontwikkelende gebiede. Hierdie tegnologie bevorder die ekonomiese gebruik van 'n hoë arbeidskomponent in padkonstruksie. Die studie stel besonderhede vir die mengselontwerp en konstruksie vir koue gemengde blokke voor. Laastens sluit die studie modelle in vir die werkverrigtingsvoorspelling van skuimbitumen mengsels. Op basis van drie-assige proewe in die laboratorium en versnelde belasting van paaie is modelle ontwikkel vir skuim bitumen mengsels wat spanningsafhanklike gedrag vertoon (die sogenaamde "granulêre" groep) om die permanente deformasie in die lae as gevolg van herhaalde verkeersbelasting te voorspel. 'n Opsomming van al die praktiese toepassings van die ontwikkelings van die navorsing word in Appendix F verskaf. Dit sluit in: • optimesering van die eienskappe van skuimbitumen, • riglyne vir gewenste samestelling van aggregaat in skuimbitumen mengsels, • ontwerp metodes vir koue skuimbitumen mengsels in die laboratorium (meng, verdigting en curing), • produksie metodes vir half-warme mensels in die laboratorium, • produksie metodes vir blokke wat met koue mengsels gemaak word, en • plaveiselontwerp metodes van strukture wat skuimbitumen lae inkorporeer. Appendix G gee 'n oorsig van statistiese tegnieke wat relevant is vir die ontwerp van eksperimente, insluitend voorbeelde van toepassings van die prosedures in plaveiselingenieurswese. Die tegnieke word selektief toegepas in die relevante hoofstukke van die verhandeling.
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Buddhavarapu, Prasad Naga Venkata Siva Rama. "CAM mix design with local aggregates." Thesis, 2011. http://hdl.handle.net/2152/ETD-UT-2011-12-4801.
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Crack Attenuating Mix (CAM) is relatively a new asphalt mixture type used by
the Texas Department of Transportation (TxDOT). These mixtures are fine graded,
designed using relatively small stone sized aggregates and screenings with a high asphalt
content, specifically for retarding the reflective cracking in thin asphalt overlays without
sacrificing rutting resistance. The main goal of this study is to promote the use of local
aggregates in CAM design. In order to achieve the goal, the development of a mix design
procedure and aggregate quality guidelines for CAM design with local aggregates are
essential. Several aggregate sources were identified and characterized in terms of their
frictional, strength, and durability properties. A refined mix design procedure is
recommended using a Superpave gyratory compactor with the capability to measure
shear stress during compaction. The emphasis was on preventing rutting and flushing
resulting from overfilling of binder in these mixtures, which was observed during
compaction by consistent shear failures. The Hamburg Wheel Tracking Device (HWTD)
was used for performance evaluation of rutting, whereas the Overlay Tester (OT) was
used for cracking evaluation. It is hypothesized that current performance criteria in terms
of HWTD and OT are too severe for being applicable to CAM mixes with local
aggregates. A modification in HWTD failure criterion is recommended and is used in
developing new aggregate guidelines. A correlation analysis was conducted relating
aggregate properties and CAM performance in rutting and cracking. Finally, aggregate
quality guidelines were developed for CAM using local aggregates based on the
correlation study. The mix design recommendations as well as aggregate guidelines and
quality criteria provided in the report are based on laboratory investigations and field
validation of these is strongly recommended before implementation.text
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Huang, Sing-Ming, and 黃新閔. "Superpave Mix Design for Gradation control." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/50620268347101743471.
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