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COLD IN-PLACE RECYCLING WITH EXPANDED ASPHALT MIX (CIREAM)Abiodun, Samuel 16 April 2014 (has links)
Cold in-place recycling with expanded asphalt mix (CIREAM) has become an accepted road rehabilitation technique in Ontario and other parts of the world given its advantages over regular cold in-place recycling (CIR) and other methods. Although CIREAM offers early strength advantages and extended paving periods among other benefits, late season CIREAM can be burdened by distresses such as ravelling, potholing and other moisture-induced damage. Limited information on the behaviour and failure mechanisms of CIREAM has also hindered its utilization in spite of the numerous benefits.
This research investigated effects of additives on foam properties of roofing asphalt flux (RAF) binder in order to evaluate the suitability of the binder for CIREAM. The study also investigated how mixture variables and test protocols affect performance properties that relate to early strength and moisture resistance of CIREAM versus CIR. Indirect tensile strength testing with moisture conditioning was used to assess the effects of asphalt cement type (80, 300 pen grades and polymer modified asphalt), conditioning time, and additives such as Portland cement, foam stabilizers, polymers and fibers. Uniaxial cyclic compression with partial confinement was used to assess effect of additives on deformation resistance of recycled mixes. Although a siloxane-based stabilizer significantly improved the stability of RAF foam, the binder may not be suitable for CIREAM due to its limited expansion. The optimum binder content was found to be around 2 percent, which is significantly higher than the minimum 1 percent currently used in Ontario. Both Portland cement and the siloxane additive exerted significant positive effects on strength behaviour and moisture resistance of the recycled mixes. In regular CIR mixes, 2 percent binder content gave desirable early strength and strain performance compared to 1 percent.
Application of controlled amounts of additives (e.g. Portland cement, foam stabilizers) and case-by-case evaluation can improve the performance properties of CIREAM and address the associated problems. The entire research effort described in this thesis was designed to provide advice on potential improvements in the CIREAM process as it is currently carried out in Ontario, and also help in developing quality control standards in CIREAM and other cold mix processes. / Thesis (Master, Chemistry) -- Queen's University, 2014-04-16 08:42:24.313
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Effect of using Organosilane with Crumb Rubber Modified Hot Mix Asphalt MixturesJanuary 2018 (has links)
abstract: Crumb rubber use in asphalt mixtures by means of wet process technology has been in place for several years in the United States with good performance record; however, it has some shortcomings such as maintaining high mixing and compaction temperatures in the field production. Organosilane (OS), a nanotechnology chemical substantially improves the bonding between aggregate and asphalt by modifying the aggregate structure from hydrophilic to hydrophobic contributing to increased moisture resistance of conventional asphalt mixtures. Use of Organosilane also reduces the mixing and compaction temperatures and facilitates similar compaction effort at lower temperatures. The objective of this research study was first to perform a Superpave mix design for Crumb Rubber Modified Binder (CRMB) gap-graded mixture with and without Organosilane; and secondly, analyse the performance of CRMB mixtures with and without Organosilane by conducting various laboratory tests. Performance Grade (PG) 64-22 binder was used to create the gap-graded Hot Mix Asphalt (HMA) mixtures for this study. Laboratory tests included rotational viscometer binder test and mixtures tests: dynamic modulus, flow number, tensile strength ratio, and C* fracture test. Results from the tests indicated that the addition of Organosilane facilitated easier compaction efforts despite reduced mixing and compaction temperatures. Organosilane also modestly increased the moisture susceptibility and resistance to crack propagation yet retaining equal rutting resistance of the CRMB mixtures. / Dissertation/Thesis / Masters Thesis Civil, Environmental and Sustainable Engineering 2018
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Performance Evaluation of Reclaimed Asphalt Pavement in Hot Mix Asphalt Modified with OrganosilaneJanuary 2018 (has links)
abstract: Use of Recycled Asphalt Pavement (RAP) in newly designed asphalt mixtures is becoming a common practice. Depending on the percentage of RAP, the stiffness of the hot mix asphalt (HMA) increases by incorporating RAP in mixes. In a climatic area such as the City of Phoenix, RAP properties are expected to be more oxidized and aged compared to other regions across the US. Therefore, there are concerns about the cracking behavior and long-term performance of asphalt mixes with high percentage of RAP. The use of Organosilane (OS) in this study was hypothesized to reduce the additional cracking potential and improve resistance to moisture damage of the asphalt mixtures when using RAP. OS has also the potential to improve the bond between the aggregate and asphalt binder. The use of OS also reduces the mixing and compaction temperatures required for asphalt mixtures, making it similar to a warm mix asphalt (WMA),
Six asphalt mixes were prepared with three RAP contents, 0%, 15% and 25%, with and without Organosilane. The mixing temperature was reduced by 10°C and the compaction temperature was reduced by 30°C. Mix designs were performed, and the volumetric properties were compared. The mixture laboratory performance was evaluated for all mixtures by conducting Dynamic Modulus, Flow Number and Tensile Strength Ratio tests.
The study findings showed that mixtures achieved better compaction at a reduced temperature of 30°C. Mixtures modified with Organosilane generally exhibited softer behavior at the extreme ends of lower and higher temperatures. The lower moduli are to reduce the potential for cracking. For the Flow Number test, the RAP mixtures with OS passed the minimum required at all traffic levels. Tensile Strength Ratio results increased with the increase in RAP percentage, and further increase was observed when OS was used. The OS reduced the sticking nature of the binder to the molds and equipment, which reduced the efforts in cleaning them.
Finally, the future use of RAP by the City of Phoenix would positively contributes to their sustainability aspiration and initiatives. The use of Organosilane may even facilitates higher percentage of RAP usage; it definitely improves the moisture resistance of asphalt mixtures, especially when lower mixing and compaction temperatures are desired or used. / Dissertation/Thesis / Masters Thesis Civil, Environmental and Sustainable Engineering 2018
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MDF kompozity AC-PVAl se zvýšenou odolností proti vlhkosti / MDF composites AC-PVAl with increased moisture resistanceRepka, Martin January 2010 (has links)
Polymerem impregnované cementové materiály představují zajímavou a perspektivní alternativu klasických portlandských cementových past. Hlavním zástupcem těchto materiálů jsou macrodefect-free (MDF) kompozity, složené z anorganického pojiva a organického polymeru. I přes řadu vynikajících mechanických vlastností je plné zavedení MDF kompozitů na trh omezené především z důvodu jejich relativně nízké odolnosti vůči vlhkosti. Jednou z možností jak zvýšit odolnost výsledného MDF vůči vlhkosti je „in situ“ síťování polymeru. V této práci byla připravena počáteční série MDF kompozitů na bázi hlinitanového cementu a polyvinylalkoholu se třemi typy organo-titanátových síťovacích činidel (Tyzory). Efekt modifikace MDF kompozitů byl hodnocen na základě zkoušek pevnosti v tahu za ohybu po uložení materiálů v různých vlhkostních podmínkách.
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Syntéza vysokopevnostních kompozitů na bázi anorganického cementu a polymeru / Synthesis of High-Strength Composites Based on Inorganic Cement and PolymerMásilko, Jiří January 2012 (has links)
The subject of the doctoral thesis is the study of moisture resistance of macro-defect-free (MDF) composites based on calcium-aluminate cement and polyvinylalcohol used as polymer. MDF cements are perspective materials providing unique properties relative to traditional cement pastes with great potential to incoming constructional utilization. But it is known that MDF cements exhibit sensitivity to water, with swelling and reduction of strength. Therefore the work is aimed in monitoring of an organic polymer effect on the moisture resistance of MDF materials and phase changes. The effects of three different organotitanate cross-linking agents on the properties were investigated. The organotitanate-modified MDF cement samples exhibited improved moisture resistance as compared to the standard samples when exposed to 100 % relative humidity or water at laboratory conditions. The influence of composition at different curing on the properties of model MDF cement samples was observed. The characterization of MDF samples was based especially on test of flexural strength, XRD, DTA/TGA and EGA, EDS and scanning electron microscopy analyses.
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Příprava MDF kompozitů se zvýšenou odolností proti vlhkosti / Preparation of MDF composites of increased moisture resistanceŽůrová, Marcela January 2015 (has links)
The subject of the thesis is to improve the moisture resistance of MDF (macro-defect-free) composites prepared on the basis of aluminous cement and polyvinyl alcohol. These materials are characterized by the absence of defects in the structure and high mechanical performance. These features make MDF composites a promising type of material that could be used in the future for construction purposes. The basic deficiency of MDF composites is insufficient resistance to water or moisture, accompanied by a significant decrease in strength. Therefore, this work deals with increasing of moisture resistance using organotitanate agent and modification of the polymer. Two types of polyvinyl alcohols differing in hydrolysis degree and degree of the polymerization has been modified. Based on the results of the measurement the effect of storage conditions on the properties and structure of prepared MDF composites was observed. The characterization of MDF composites were realized by measurement of flexural strength in bending, scanning electron microscopy with EDS analysis, TG-DTA-EGA, water absorption and consequently the porosity of all prepared MDF composites.
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Hampa som isoleringsmaterial : En studie av hampas isolerande egenskaper och materialets framtida möjligheter / Hemp as insulation material : A study of hemp´s insulating properties and the material´s future potentialLundholm, Kelly, Hillerbratt, Emma January 2021 (has links)
Historically, energy use in the operational phase has accounted for most of a building’s climate impact. This has been changed in recent decades because there has been a focus on developing energy-efficient buildings. A larger part of a building’s climate impact is caused by material manufacturing and production. To reduce a building’s climate impact alternative insulation materials can be used, for example hemp fibre insulation which is an organic and non-toxic material. The aim of this study is to find out if hemp fibre insulation can be implemented as a standard insulation material. By examining what factors are vital when choosing an insulation material this work intends to find out if the insulation properties of hemp insulation can fulfill the requirements by the constructor. To fulfill the aim, a combination of interviews, surveys and theoretical studies was used. The most crucial aspects when choosing insulation material are fire resistance, thermal conductivity and health aspects for the construction workers. The benefits with hemp insulation are primarily the negative emissions of carbon dioxide seen from a life cycle perspective, the possibility to cultivate the product within Sweden, its reusability and recyclability and that the insulation material are free from hazardous substances. The disadvantages are higher thermal conductivity, higher market price, lower fire resistance and limited accessibility on the Swedish market. Due to the disadvantages, it is difficult to implement hemp insulation as a standard insulation material today. The conclusions are that the environmental impact is not decisive for an entrepreneur today when choosing insulation material. However, it will most likely become a more essential factor in the future. Improving the building sector’s knowledge regarding hemp insulation, will presumably increase the usage of it. Although, for hemp insulation to become a competitor in the future, it is substantial to increase its fire resistance and the accessibility on the Swedish market. The development of the material and the market may be a contributing factor to achieve the global and national environmental goals.
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Влияние состояния поверхностей оптических деталей на технические характеристики сборок, склеенных с помощью клея Бальзамин М : магистерская диссертация / Influence of the state of the surfaces of optical parts on the technical characteristics of assemblies glued with “Balsamin M” glueСпицына, А. Ю., Spicyna, A. J. January 2021 (has links)
Исследовано влияние состояния поверхностей оптических сборок склеенных из стекол ЛК7 и ТФ7 на технические характеристики сборок, склеенных клеем «Бальзамин М», при воздействии различных климатических условий, их деформации, а также на прочность клеевого соединения при равномерном отрыве сборок, изготовленных из стекла К8, склеенных клеем «Бальзамин М». / The influence of the state of the surfaces of optical assemblies glued from LK7 and TF7 glasses on the technical characteristics of assemblies glued with "Balzamin M" glue, under the influence of various climatic conditions, their deformation, as well as on the strength of the adhesive bond with uniform tearing of assemblies made of K8 glass glued with "Balzamin M" glue.
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