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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Rekultivuotų sąvartynų, esančių Kauno rajone, dengiamojo sluoksnio tyrimas / Investigation of the condition of the cover layer of closed landfills in the Kaunas district

Makaveckas, Tomas 30 May 2012 (has links)
Populiariausias atliekų valdymo metodas ne tik pasaulyje, bet ir Lietuvoje vis dar išlieka atliekų deponavimas sąvartynuose. Lietuvoje, 2009 metų duomenimis, sąvartynuose buvo pašalinta 90,6 % atliekų. Šiame darbe trumpai aptariama atliekų sąvartynų įrengimo, bei sąvartyno lauko uždengimo tvarka ir rekomendacijos. Aptariami keturiuose uždarytuose Kauno rajono sąvartynuose (Digrių, Gaižėnėlių, Miškinių ir Ilgakiemio) atlikti uždengiamojo sluoksnio būklės tyrimai. Remiantis gautais tyrimų duomenimis daromos išvados apie sąvartynų būklę. Gauti rezultatai rodo, jog ne visi sąvartynai rekultivuojami laikantis taisyklių ir rekomendacijų. Kadangi pastaraisiais dešimtmečiais labai susirūpinta švarios aplinkos išsaugojimu, ekologija ir aplinkos taršos mažinimu, aktualus klausimas išlieka tinkamas atliekų tvarkymas, sąvartynų tinklo optimizavimas (taip pat visiškas jų atsisakymas, dėl valstybių politikos kitaip tvarkyti atliekas, pavyzdžiui, jas deginant), Lietuvoje svarbus klausimas yra senų ir nebenaudojamų savartynų uždarymas. Reikia pasirinkti tinkamą sąvartyno uždarymo būdą, kadangi blogai rekultivuotas sąvartynas, gali sukelti didelę ekologinę katastrofą. / The most popular method of waste management not only in the world, but also in Lithuania, remains depositing waste in landfills. In Lithuania (according to the 2009 data) 90.6% of waste was deposited at the landfills. This work discusses the installation of the landfill, the procedures and recommendations of creating the final landfill covers. There was performed a research on four closed landfills in Kaunas district (Digriai, Gaižėnėliai, Miškiniai and Ilgakiemis) to find out the condition of landfill’s cover layer. According to the findings, conclusions about the condition of these landfills are made. The results show that not all landfills undergo recultivation in accordance with the rules and guidelines. Preservation of the clean environment, ecology and reduction of the environmental pollution is the major concern for the last decades and the most relevant question remains the proper waste management, optimization of the landfill network (as well as the complete abandonment of the landfills, because of different waste management policies, such as incineration). Still, Lithuania has to deal with old and disused landfills, so the proper way to close the landfill must be chosen, because poorly recultivated landfill can cause large ecological catastrophe.
2

AvaliaÃÃo do Cultivo de GramÃneas na SuperfÃcie de Aterro SanitÃrio, com Ãnfase para a ReduÃÃo da EmissÃo de Metano e DiÃxido de Carbono para a Atmosfera / Evaluation of Growing Grass Surface Landfill, with Emphasis on the Reduction of Emission of Methane and Carbon Dioxide to the Atmosphere

Gemmelle Oliveira Santos 20 December 2012 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Nesta pesquisa, uma CÃlula Experimental (CE) de ResÃduos SÃlidos Urbanos (RSU) foi instalada numa Ãrea nÃo utilizada do Aterro SanitÃrio Metropolitano Oeste de Caucaia (ASMOC), RegiÃo Metropolitana de Fortaleza, com o objetivo de se estudar o comportamento de gramÃneas na sua superfÃcie, visando a reduÃÃo das emissÃes de CH4 e CO2 para a atmosfera e a produÃÃo de biomassa vegetal. As estimativas das emissÃes de gases foram realizadas por meio de ensaios com placa de fluxo estÃtico na cobertura convencional (branco) e nas coberturas cultivadas, alÃm das mediÃÃes feitas no dreno; todos em duas campanhas. Os cultivos de capim MombaÃa, Massai, Andropogon, Buffel e da grama Bermuda foram avaliados com relaÃÃo as caracterÃsticas morfogÃnicas, estruturais, produtivas e nutricionais. A Ãrea que recebeu a CE foi previamente estudada por meio do reconhecimento do perfil estratigrÃfico do subsolo e do nÃvel d‟Ãgua, caracterizaÃÃo dos solos em termos geofÃsicos (granulometria, limites de consistÃncia, compactaÃÃo Proctor Normal, permeabilidade à Ãgua) e quanto à fertilidade. Os RSU foram estudados quanto à composiÃÃo gravimÃtrica, densidade aparente, teor de umidade e seu lixiviado analisado do ponto de vista fÃsico-quÃmico. Os gases emitidos pelo dreno, na primeira campanha (1ÂC) foram compostos, em mÃdia, por 14,7% de CO2, 8,0% de CH4, 11,4% de O2 e 65,9% de outros gases. Na segunda campanha (2ÂC) houve um aumento na concentraÃÃo (%) dos dois principais gases de interesse (CO2: 0,3 vezes e CH4: 0,5 vezes) e reduÃÃo na concentraÃÃo dos demais (O2: 0,2 vezes e OG: 0,1 vezes): 19,0% de CO2, 11,8% de CH4, 8,7% de O2 e 60,4% de outros gases. Os gases emitidos pela cobertura (branco) foram (em %) menores que os emitidos pelo dreno, mostrando retenÃÃo: 1ÂC = 11,6% de CO2, 6,5% de CH4, 9,1% de O2 e 72,7% de outros gases; 2ÂC = 14,9% de CO2, 9,4% de CH4, 7,2% de O2 e 68,5% de outros gases. Em relaÃÃo aos fluxos mÃssicos houve aumento entre as campanhas (mÃdia): 2,5 x 10-3 e 3,6 x 10-3 g/m2.s de CH4 (1ÂC e 2ÂC, respectivamente), 1,2 x 10-2 e 1,5 x 10-2 g/m2.s de CO2 (1ÂC e 2ÂC). Os fluxos volumÃtricos foram (mÃdia): 4,0 x 10-6 e 5,7 x 10-6 m3/m2.s de CH4 (1ÂC e 2ÂC) e 7,0 x 10-6 e 8,8 x 10-6 m3/m2.s de CO2 (1ÂC e 2ÂC). Cabe observar que os fluxos estiveram dentro dos intervalos da literatura. Em relaÃÃo aos cultivos, observou-se que mesmo colocadas sobre solo tÃpico de aterro sanitÃrio e sem tratamento especial na cobertura ou no cultivo, as sementes dos quatro capins estudados e da grama Bermuda apresentaram germinaÃÃo dentro dos prazos biolÃgicos previstos. Assim, houve sobrevivÃncia dessas espÃcies sobre o solo do aterro sanitÃrio, porÃm com indicadores de desenvolvimento vegetal menores em relaÃÃo a literatura, contribuindo para isso o efeito negativo da extrema compactaÃÃo da cobertura e o baixo grau de fertilidade do solo. Cada cultivo teve uma capacidade diferente de impedir as emissÃes dos gases pela cobertura. Em ordem decrescente, observou-se (mÃdia): MombaÃa (2,6 e 3,8% de CH4 na 1ÂC/2ÂC; 4,6 e 6,0% de CO2 na 1ÂC/2ÂC), Massai (2,0 e 2,8% de CH4; 3,5 e 4,5% de CO2), Andropogon (1,1 e 1,5% de CH4; 1,9 e 2,5% de CO2), Bermuda (0,9 e 1,3% de CH4; 1,6 e 2,0% de CO2) e capim Buffel (0,4 e 0,6% de CH4; 0,5 e 0,6% de CO2). Os fluxos mÃssicos e volumÃtricos tambÃm foram menores no solo cultivado com capim MombaÃa e maiores no capim Buffel e isso manteve relaÃÃo com as principais caracterÃsticas morfogÃnicas, estruturais, produtivas e nutricionais utilizadas na avaliaÃÃo da sobrevivÃncia e desenvolvimento dos cultivos. / An Urban Solid Waste (USW) Experimental Cell (EC) was set up in an unused area of the West Metropolitan Landfill in Caucaia (ASMOC), in the Metropolitan Region of Fortaleza, with the aim of studying the behavior of different grasses planted on its cover layer in order to reduce atmospheric emissions of CO2 and CH4 and for the production of plant biomass. Gas emissions were tested with static flow plates on the normal cover layer (blank) and on the planted areas, in addition to the measurements taken on the landfill drainage. All measurements were made in two different campaigns. The morphogenesis, structural, productive and nutritional features of the Mombasa, Massai, Andropogon, Buffel and Bermuda grasses were evaluated. The area on which the EC was located was studied prior to the seeding, including a survey of the subsoil stratigraphic profile and groundwater levels, a geophysical soil characterization (grain size, Atterberg limits, normal Proctor compaction, water permeability) and fertility. The USW was studied for its gravimetric composition, density and moisture content and its leachate was analyzed from a physical and chemical perspective. The gases emitted by the drainage in the first campaign (C1) were composed on average by 14.7% CO2, 8.0% CH4, 11.4% O2, and 65.9% of other gases. In the second campaign (C2) there was an increase in the concentration (%) of the two main gases of interest (CO2: 0.3 times; CH4: 0.5 times) and a reduction in the concentration of the others (O2: 0.2 times, and other gases 0.1 times), with the following concentrations: CO2 19.0%, CH4 11.8%, O2 8.7%, and 60.4% of other gases. The gas emissions of the normal cover layer (blank) were lower than those of the drainage, showing a certain retention: C1: CO2 11.6%, CH4 6.5%, O2 9.1% and 72.7% of other gases; C2: CO2 14.9%, CH4 9.4%, O2 7.2% and 68.5% of other gases. Regarding the mass flows, there was an increase between the two campaigns (mean values): 2.5 x 10-3 and 3.6 x 10-3 g/m2.s of CH4 (C1 and C2, respectively), and 1.2 x 10-2 and 1.5 x 10-2 g/m2.s of CO2 (also for C1 and C2, respectively). The volumetric flows were the following (mean values): 4.0 x 10-6 and 5.7 x 10-6 m3/m2.s of CH4 (C1 and C2); and 7.0 x 10-6 and 8.8 x 10-6 m3/m2.s of CO2 (C1 and C2). The flows were within the ranges reported in the literature. Regarding the grass crops, it was observed that even though they were planted on a typical landfill soil without any special soil or cultivation treatment, the seeds of all five studied grasses germinated within the expected biological times. These species survived on the soil of the landfill yet presented smaller plant development indicators than those reported in the literature. The negative effect of an extreme soil compaction and low soil fertility contributed to such lower developmental results. Each crop showed a different ability to prevent gas emissions through the cover layer. We present them in descending order (mean values), namely: Mombasa (2.6% and 3.8% of CH4 in C1/C2, and 4.6% and 6.0% of CO2 in C1/ C2); Massai (2.0% and 2.8% of CH4, and 3.5% and 4.5% of CO2); Andropogon (1.1% and 1.5% of CH4, 1.9% and 2.5% of CO2); Bermuda (0.9% and 1.3% of CH4, 1.6% and 2.0% of CO2); and Buffel (0.4% and 0.6% of CH4, 0.5% and 0.6% of CO2). The volumetric and mass flows were lower in the soil planted with Mombasa grass and higher in that planted with Buffel. This was related to the main morphogenesis, structural, nutritional and productive features used in the assessment of crop survival and development.
3

Characterization of Mineral-Bonded Composites As Damping Layers Against Impact Loading

Leicht, Lena 13 March 2024 (has links)
The present work aims at finding suitable mineral-bonded strengthening layers to protect steel-reinforced concrete (RC) structures from impact events. The strengthening layers are applied to the impact-facing side and absorb large parts of the impact energy. In this way, they protect the RC structures from the impact events. The multilayered strengthening layers consist of a cover layer and a damping layer. The cover layers possess a high strength and a high modulus of elasticity. The impactor directly hits the cover layer, which spreads the impact force to larger areas of the damping layer below. The strengths and moduli of elasticity of the damping layers are minor, and they absorb impact energy, converting it into friction, heat, or potential energy. Several materials have been tested as damping layers, including a concrete mixed with waste tire rubber aggregates, two types of lightweight concrete, and two types of infra-lightweight concrete. The cover layers tested include carbon-fiber-reinforced concrete and various short-fiber-reinforced concretes, some of which are reinforced with 3D hybrid pyramidal truss reinforcing structures. At first, the dynamic material properties were determined with the help of a tensile and a compressive split Hopkinson bar. The small-scale experiments serve to investigate the dynamic material behavior. At the same time, they are the basis for an eventual later numerical analysis of the strengthening layers. A numerical analysis enables the variation of the material parameters. Lastly, large-scale tests with RC cuboids that were fully supported were performed. A choice of cover and damping layer materials was compared to unstrengthened RC cuboids. The first set of experiments strived to vary the damping layer to find the most suitable one that absorbs the highest amount of incident energy, thus minimizing the damage to the RC cuboid. Afterward, the best damping layer material was combined with different cover layers to figure out the best cover layer option.:Abstract i Kurzfassung iii List of Symbols xv List of Abbreviations xix 1 Objectives, Working Program, and Structure 1 1.1 Motivation 1 1.2 Overall Objectives 1 1.3 Working Program 1 2 State of the Art and Theoretical Background 3 2.1 Impact on Structural Elements 3 2.1.1 Soft and Hard Impact 3 2.1.2 Failure Modes Under Hard Impact Conditions 3 2.1.3 Large-Scale Impact Experiments 4 2.1.4 Impact Protection Layers 4 2.2 Introduction of Impact Protection Principles 4 2.2.1 Impact Protection in Nature 4 2.2.2 Technical Impact Protection Examples 9 2.2.3 Summary of Impact Protection Principles and Usable Materials 14 2.3 Mineral-Bonded Damping Layer Materials 15 2.3.1 Waste Tire Rubber Concrete 15 2.3.2 All-Lightweight Aggregate Concrete 16 2.3.3 Infra-Lightweight Concrete 17 2.4 Mineral-Bonded Cover Layer Materials 18 2.4.1 Strain-Hardening Cementitous Composites 18 2.4.2 Textile Reinforced Concrete 19 2.4.3 Hybrid-Fiber Reinforced Concrete 19 2.5 Bond Between Different Strengthening Layers 20 3 Materials under Investigation 21 3.1 Specimen Preparation 21 3.2 Damping Layer Materials 22 3.2.1 Waste Tire Rubber Concrete (WTRC) 22 3.2.2 All-Lightweight Aggregate Concrete With Liapor Aggregates (ALWAC-L) 23 3.2.3 All-Lightweight Aggregate Concrete With Ulopor Aggregates (ALWAC-U) 23 3.2.4 Porous Lightweight Concrete (PLC) 23 3.2.5 Infra-Lightweight Concrete (ILC) 23 3.2.6 Comparison of the Damping Layer Materials 24 3.3 Cover Layer Materials 27 3.3.1 Pagel TF10 CARBOrefit With Carbon Textile Reinforcement (P-C) 27 3.3.2 Strain-Hardening Limestone Calcined Clay Cement (SHLC3) 27 3.3.3 Comparison of the Cover Layer Materials 28 3.4 Partially Loaded Areas 30 4 Methodology of Split Hopkinson Bar Experiments 35 4.1 Experimental Setup and Methodology 35 4.1.1 Compressive Split Hopkinson Bar 35 4.1.2 Tensile Split Hopkinson Bar 36 4.1.3 Instrumentation 39 4.2 Evaluation Process 39 4.2.1 Impedance 40 4.2.2 Raw Data Analysis, Filtering, and Time-Shifting of Pulses 41 4.2.3 Stresses and Strains 42 4.2.4 Deformations 50 4.2.5 Forces and Impulses 51 4.2.6 Energy Absorption 52 4.2.7 Fracture Energy 53 4.2.8 Averaging of the Results 54 5 Compressive Split Hopkinson Bar Experiments 57 5.1 Failure Modes 57 5.2 Stresses and Strains 58 5.2.1 Dynamic Compressive Strength 58 5.2.2 DIF 59 5.3 Deformations 60 5.4 Forces and Impulses 61 5.4.1 Relative Transmitted Force 61 5.4.2 Impulse Transmission 63 5.4.3 Reduction of the Pulse Inclination 64 5.5 Energy Absorption 64 5.6 Conclusions 66 6 Tensile Split Hopkinson Bar Experiments 69 6.1 Failure Modes 69 6.2 Stresses and Strains 70 6.2.1 Dynamic Tensile Strength 70 6.2.2 DIF 71 6.3 Deformations 72 6.4 Forces and Impulses 73 6.4.1 Relative Transmitted Force 73 6.4.2 Impulse Transmission 74 6.4.3 Reduction of the Pulse Inclination 75 6.5 Energy Absorption 75 6.6 Fracture Energy 77 6.7 Conclusions 78 7 Methodology of Cuboid Experiments 79 7.1 Experimental Program 79 7.1.1 Specimen Dimensions and Experimental Setup 79 7.1.2 Experimental Scheme 81 7.2 Measurements Taken During the Experiments 83 7.2.1 Light Barriers 84 7.2.2 Resistor 84 7.2.3 Strain Gauges 84 7.2.4 Laser Doppler Vibrometer 85 7.2.5 Accelerometers 85 7.2.6 Load Cells 85 7.2.7 High-Speed Cameras and DIC 85 7.3 Measurements Taken Before and After the Experiments 86 7.3.1 Impactor Indentation 86 7.3.2 Burst Mass 86 7.3.3 Ultrasonic Pulse Velocity Measurements 86 7.3.4 Stimulation 87 7.4 Evaluation Process 88 7.4.1 Fracture and Damage Process 88 7.4.2 Impactor Velocity, Deceleration, Force, Stress, and Stress Rate 88 7.4.3 Impactor Indentation, Strain, and Strain Rate 90 7.4.4 Vertical Cuboid Deformation, Velocity, and Acceleration 92 7.4.5 Lateral Cuboid Deformation, Velocity, and Acceleration 93 7.4.6 Relative Cuboid Elongation in X- and Y-Direction 93 7.4.7 Strain Measurements on the Reinforcement Bars 94 7.4.8 Path and Derivative of the Support Forces 95 7.4.9 Burst Mass 96 7.4.10 Ultrasonic Pulse Velocity Measurements 96 7.4.11 Stimulation 97 7.4.12 Impulse and Momentum Conservation 99 7.4.13 Energy Conservation 100 7.4.14 Estimation of the Eigenfrequency of the Cuboids 101 8 Damping Layer Variation in Cuboid Experiments 103 8.1 Fracture and Damage Process 103 8.2 Impactor Velocity, Deceleration, and Force 105 8.3 Impactor Indentation 108 8.4 Vertical Cuboid Deformation, Velocity, and Acceleration 110 8.5 Lateral Cuboid Deformation, Velocity, and Acceleration 113 8.6 Relative Cuboid Elongation in X- and Y-Direction 115 8.7 Path and Derivative of the Support Forces 118 8.8 Ultrasonic Pulse Velocity Measurements 120 8.9 Stimulation With the Impulse Hammer 121 8.10 Stimulation With the Steel Impactor 124 8.11 Overview Over Forces, Stresses, Strains, and Their Rates 128 8.12 Impulse and Momentum Conservation 133 8.13 Energy Conservation 135 8.14 Dimensioning of the Required Damping Layer Thickness Depending on the Loading Velocity 136 8.15 Conclusions 137 9 Cover Layer Variation in Cuboid Experiments 139 9.1 Fracture and Damage Process 139 9.2 Impactor Velocity, Deceleration, and Force 141 9.3 Impactor Indentation 144 9.4 Vertical Cuboid Deformation, Velocity, and Acceleration 145 9.5 Lateral Cuboid Deformation, Velocity, and Acceleration 147 9.6 Relative Cuboid Elongation in X- and Y-Direction 149 9.7 Path and Derivative of the Support Forces 150 9.8 Ultrasonic Pulse Velocity Measurements 152 9.9 Stimulation With the Impulse Hammer 153 9.10 Stimulation With the Steel Impactor 155 9.11 Overview Over Forces, Stresses, Strains, and Their Rates 157 9.12 Impulse and Momentum Conservation 162 9.13 Energy Conservation 163 9.14 Conclusions 164 10 Conclusions of the Cuboid Experiments 167 10.1 Main Findings 167 10.2 Most Relevant Sensor Positions and Measurements 167 10.2.1 Digital Image Correlation (DIC) of the Impactor 167 10.2.2 Lateral Acceleration 167 10.2.3 Digital Image Correlation (DIC) of the RC Cuboid 168 10.2.4 Ultrasonic Pulse Velocity (UPV) Measurements 168 10.2.5 Stimulation With the Impulse Hammer and the Steel Impactor 168 10.3 Suggested Improvements to the Setup 168 10.3.1 High-Speed Cameras (HSC) 168 10.3.2 Acceleration Sensors 169 10.3.3 Support Forces 169 10.3.4 Strain Gauges 169 10.3.5 Temperature Sensors 169 10.4 Comparison of the Material Behavior in Compressive SHB and Cuboid Experiments 169 10.4.1 Scattering of Measured Values 169 10.4.2 Failure Modes 170 10.4.3 Loading and Strain Rates 170 10.4.4 Influences of Inertia 170 10.4.5 Forces and Stresses 171 10.4.6 Energy Absorption 171 11 Summary and Conclusions 173 11.1 Compressive SHB Experiments 173 11.2 Tensile SHB Experiments 173 11.3 Damping Layer Variation in Cuboid Experiments 174 11.4 Cover Layer Variation in Cuboid Experiments 174 11.5 Conclusions 175 12 Outlook 177 12.1 Split Hopkinson Bar Testing 177 12.2 Strengthening Procedure 177 12.3 Large-Scale Impact Testing 177 12.4 Design 178 Bibliography 179 List of Figures 193 List of Tables 199 / Die vorliegende Arbeit beschäftigt sich mit der Verstärkung von Stahlbetonbauteilen gegen Impaktbeanspruchungen. Es wurden mineralisch gebundene Verstärkungsschichten entwickelt, die auf der impaktzugewandten Seite aufgebracht wurden und große Teile der Impaktenergie umwandelten, um somit die darunterliegenden Bauteile zu schützen. Die Verstärkungsschichten sind mehrlagig aufgebaut und die Materialien werden in Deck- und Dämpfungsschichten unterschieden. Dabei sind die Deckschichtmaterialien solche, die eine große Festigkeit und Steifigkeit besitzen. Sie werden direkt durch den Impaktor getroffen und sollen die Impaktlast auf einen größeren Bereich der darunterliegenden Dämpfungsschichten verteilen. Die Dämpfungsschichten sind weniger fest und steif und sollen die Impaktenergie in Reibungs-, Wärme- und innere Energie umwandeln. Als Dämpfungsschichtmaterialien wurden ein Beton mit Altgummizuschlägen, zwei unterschiedliche Leichtbetone und zwei Infraleichtbetone geprüft. Unter den geprüften Deckschichtmaterialien befanden sich ein Carbonbeton und unterschiedliche Mischungen mit Kurzfaserbetonen, die teilweise auch mit hybriden 3D Bewehrungsstrukturen bewehrt wurden. Zunächst wurden die Materialen unter dynamischer Druck- und Zugbelastung im Split-Hopkinson-Bar geprüft. Diese kleinteiligen Versuche sollen dem Verständnis des dynamischen Materialverhaltens dienen und bilden gleichzeitig die Grundlage für eine mögliche spätere numerische Analyse der Verstärkungsschichtmaterialien, die gleichzeitig die Variation der Materialeigenschaften von Verstärkungsschichten erlaubt. Anschließend wurden die unterschiedlichen Dämpfungs- und Deckschichtmaterialien in einem größeren Probenmaßstab untersucht. Die Probekörper, die unverstärkt sowie unterschiedlich verstärkt untersucht wurden, waren vollflächig gelagerte Stahlbetonquader. Zunächst wurde das Dämpfungsschichtmaterial variiert, um die Dämpfungsschicht zu finden, die am meisten Energie umwandeln und somit die Schädigung der Stahlbetonquader am effizientesten reduzieren kann. Diese wurde danach unter unterschiedlichen Deckschichten kombiniert, um das geeignetste Deckschichtmaterial zu ermitteln.:Abstract i Kurzfassung iii List of Symbols xv List of Abbreviations xix 1 Objectives, Working Program, and Structure 1 1.1 Motivation 1 1.2 Overall Objectives 1 1.3 Working Program 1 2 State of the Art and Theoretical Background 3 2.1 Impact on Structural Elements 3 2.1.1 Soft and Hard Impact 3 2.1.2 Failure Modes Under Hard Impact Conditions 3 2.1.3 Large-Scale Impact Experiments 4 2.1.4 Impact Protection Layers 4 2.2 Introduction of Impact Protection Principles 4 2.2.1 Impact Protection in Nature 4 2.2.2 Technical Impact Protection Examples 9 2.2.3 Summary of Impact Protection Principles and Usable Materials 14 2.3 Mineral-Bonded Damping Layer Materials 15 2.3.1 Waste Tire Rubber Concrete 15 2.3.2 All-Lightweight Aggregate Concrete 16 2.3.3 Infra-Lightweight Concrete 17 2.4 Mineral-Bonded Cover Layer Materials 18 2.4.1 Strain-Hardening Cementitous Composites 18 2.4.2 Textile Reinforced Concrete 19 2.4.3 Hybrid-Fiber Reinforced Concrete 19 2.5 Bond Between Different Strengthening Layers 20 3 Materials under Investigation 21 3.1 Specimen Preparation 21 3.2 Damping Layer Materials 22 3.2.1 Waste Tire Rubber Concrete (WTRC) 22 3.2.2 All-Lightweight Aggregate Concrete With Liapor Aggregates (ALWAC-L) 23 3.2.3 All-Lightweight Aggregate Concrete With Ulopor Aggregates (ALWAC-U) 23 3.2.4 Porous Lightweight Concrete (PLC) 23 3.2.5 Infra-Lightweight Concrete (ILC) 23 3.2.6 Comparison of the Damping Layer Materials 24 3.3 Cover Layer Materials 27 3.3.1 Pagel TF10 CARBOrefit With Carbon Textile Reinforcement (P-C) 27 3.3.2 Strain-Hardening Limestone Calcined Clay Cement (SHLC3) 27 3.3.3 Comparison of the Cover Layer Materials 28 3.4 Partially Loaded Areas 30 4 Methodology of Split Hopkinson Bar Experiments 35 4.1 Experimental Setup and Methodology 35 4.1.1 Compressive Split Hopkinson Bar 35 4.1.2 Tensile Split Hopkinson Bar 36 4.1.3 Instrumentation 39 4.2 Evaluation Process 39 4.2.1 Impedance 40 4.2.2 Raw Data Analysis, Filtering, and Time-Shifting of Pulses 41 4.2.3 Stresses and Strains 42 4.2.4 Deformations 50 4.2.5 Forces and Impulses 51 4.2.6 Energy Absorption 52 4.2.7 Fracture Energy 53 4.2.8 Averaging of the Results 54 5 Compressive Split Hopkinson Bar Experiments 57 5.1 Failure Modes 57 5.2 Stresses and Strains 58 5.2.1 Dynamic Compressive Strength 58 5.2.2 DIF 59 5.3 Deformations 60 5.4 Forces and Impulses 61 5.4.1 Relative Transmitted Force 61 5.4.2 Impulse Transmission 63 5.4.3 Reduction of the Pulse Inclination 64 5.5 Energy Absorption 64 5.6 Conclusions 66 6 Tensile Split Hopkinson Bar Experiments 69 6.1 Failure Modes 69 6.2 Stresses and Strains 70 6.2.1 Dynamic Tensile Strength 70 6.2.2 DIF 71 6.3 Deformations 72 6.4 Forces and Impulses 73 6.4.1 Relative Transmitted Force 73 6.4.2 Impulse Transmission 74 6.4.3 Reduction of the Pulse Inclination 75 6.5 Energy Absorption 75 6.6 Fracture Energy 77 6.7 Conclusions 78 7 Methodology of Cuboid Experiments 79 7.1 Experimental Program 79 7.1.1 Specimen Dimensions and Experimental Setup 79 7.1.2 Experimental Scheme 81 7.2 Measurements Taken During the Experiments 83 7.2.1 Light Barriers 84 7.2.2 Resistor 84 7.2.3 Strain Gauges 84 7.2.4 Laser Doppler Vibrometer 85 7.2.5 Accelerometers 85 7.2.6 Load Cells 85 7.2.7 High-Speed Cameras and DIC 85 7.3 Measurements Taken Before and After the Experiments 86 7.3.1 Impactor Indentation 86 7.3.2 Burst Mass 86 7.3.3 Ultrasonic Pulse Velocity Measurements 86 7.3.4 Stimulation 87 7.4 Evaluation Process 88 7.4.1 Fracture and Damage Process 88 7.4.2 Impactor Velocity, Deceleration, Force, Stress, and Stress Rate 88 7.4.3 Impactor Indentation, Strain, and Strain Rate 90 7.4.4 Vertical Cuboid Deformation, Velocity, and Acceleration 92 7.4.5 Lateral Cuboid Deformation, Velocity, and Acceleration 93 7.4.6 Relative Cuboid Elongation in X- and Y-Direction 93 7.4.7 Strain Measurements on the Reinforcement Bars 94 7.4.8 Path and Derivative of the Support Forces 95 7.4.9 Burst Mass 96 7.4.10 Ultrasonic Pulse Velocity Measurements 96 7.4.11 Stimulation 97 7.4.12 Impulse and Momentum Conservation 99 7.4.13 Energy Conservation 100 7.4.14 Estimation of the Eigenfrequency of the Cuboids 101 8 Damping Layer Variation in Cuboid Experiments 103 8.1 Fracture and Damage Process 103 8.2 Impactor Velocity, Deceleration, and Force 105 8.3 Impactor Indentation 108 8.4 Vertical Cuboid Deformation, Velocity, and Acceleration 110 8.5 Lateral Cuboid Deformation, Velocity, and Acceleration 113 8.6 Relative Cuboid Elongation in X- and Y-Direction 115 8.7 Path and Derivative of the Support Forces 118 8.8 Ultrasonic Pulse Velocity Measurements 120 8.9 Stimulation With the Impulse Hammer 121 8.10 Stimulation With the Steel Impactor 124 8.11 Overview Over Forces, Stresses, Strains, and Their Rates 128 8.12 Impulse and Momentum Conservation 133 8.13 Energy Conservation 135 8.14 Dimensioning of the Required Damping Layer Thickness Depending on the Loading Velocity 136 8.15 Conclusions 137 9 Cover Layer Variation in Cuboid Experiments 139 9.1 Fracture and Damage Process 139 9.2 Impactor Velocity, Deceleration, and Force 141 9.3 Impactor Indentation 144 9.4 Vertical Cuboid Deformation, Velocity, and Acceleration 145 9.5 Lateral Cuboid Deformation, Velocity, and Acceleration 147 9.6 Relative Cuboid Elongation in X- and Y-Direction 149 9.7 Path and Derivative of the Support Forces 150 9.8 Ultrasonic Pulse Velocity Measurements 152 9.9 Stimulation With the Impulse Hammer 153 9.10 Stimulation With the Steel Impactor 155 9.11 Overview Over Forces, Stresses, Strains, and Their Rates 157 9.12 Impulse and Momentum Conservation 162 9.13 Energy Conservation 163 9.14 Conclusions 164 10 Conclusions of the Cuboid Experiments 167 10.1 Main Findings 167 10.2 Most Relevant Sensor Positions and Measurements 167 10.2.1 Digital Image Correlation (DIC) of the Impactor 167 10.2.2 Lateral Acceleration 167 10.2.3 Digital Image Correlation (DIC) of the RC Cuboid 168 10.2.4 Ultrasonic Pulse Velocity (UPV) Measurements 168 10.2.5 Stimulation With the Impulse Hammer and the Steel Impactor 168 10.3 Suggested Improvements to the Setup 168 10.3.1 High-Speed Cameras (HSC) 168 10.3.2 Acceleration Sensors 169 10.3.3 Support Forces 169 10.3.4 Strain Gauges 169 10.3.5 Temperature Sensors 169 10.4 Comparison of the Material Behavior in Compressive SHB and Cuboid Experiments 169 10.4.1 Scattering of Measured Values 169 10.4.2 Failure Modes 170 10.4.3 Loading and Strain Rates 170 10.4.4 Influences of Inertia 170 10.4.5 Forces and Stresses 171 10.4.6 Energy Absorption 171 11 Summary and Conclusions 173 11.1 Compressive SHB Experiments 173 11.2 Tensile SHB Experiments 173 11.3 Damping Layer Variation in Cuboid Experiments 174 11.4 Cover Layer Variation in Cuboid Experiments 174 11.5 Conclusions 175 12 Outlook 177 12.1 Split Hopkinson Bar Testing 177 12.2 Strengthening Procedure 177 12.3 Large-Scale Impact Testing 177 12.4 Design 178 Bibliography 179 List of Figures 193 List of Tables 199
4

Aplica??o de dois modelos de balan?o h?drico para estudo de Camada de cobertura de aterro sanit?rio utilizando solo e Res?duo da constru??o civil (RCC)

Rios, Daiane do Carmo 14 September 2016 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2017-07-12T01:22:06Z No. of bitstreams: 1 Disserta??o Daiane do Carmo.pdf: 4697687 bytes, checksum: a37b7f9d37bd854f2fb6862074c46fd4 (MD5) / Made available in DSpace on 2017-07-12T01:22:06Z (GMT). No. of bitstreams: 1 Disserta??o Daiane do Carmo.pdf: 4697687 bytes, checksum: a37b7f9d37bd854f2fb6862074c46fd4 (MD5) Previous issue date: 2016-09-14 / Funda??o de Amparo ? Pesquisa do Estado da Bahia - FAPEB / The water balance is an important aspect on development of a landfill project, and the choice of material for the cover layer will influence the generation of percolated liquids. Considering the composition and characteristics of cover layers, it becomes necessary the conventional material substitution. Therefore, this study compared the construction civil waste (CCW) to the soil from the university campus - UEFS in Feira de Santana/BA as used in evapotranspiration cover layer for landfill, using the water balance models Fenn et al. (1975) and S?o Mateus et al. (2012). The results showed that both materials have the same behavior for the Fenn et al. (1975) method, where the CCW generates less liquid than MSW to the ground. By the method of S?o Mateus et al. (2012), the CCW and the soil allow the passage of water to the MSW in different behaviors, and the soil promoted greater liquid infiltration, about 95.5% higher than the CCW. When the methods were compared, S?o Mateus et al. (2012) presented higher water infiltration to the MSW in the simulation with the soil, in relation to the method of Fenn et al. (1975), and smaller with the CCW, this occurs due to the distinction of the input parameters for the materials, highlighting the influence of the permeability coefficient in the water balance. / O balan?o h?drico ? parte importante no processo de elabora??o de um projeto de aterro sanit?rio, visto que a escolha do material para a camada de cobertura influenciar? na gera??o de l?quidos percolados. Tendo em vista a necessidade da utiliza??o de materiais para a composi??o das diversas camadas dos sistemas de cobertura, torna-se indispens?vel o estudo de materiais alternativos para a substitui??o dos materiais usados originalmente. Para tanto, este trabalho comparou o res?duo da constru??o civil (RCC) com o solo do campus universit?rio da UEFS em Feira de Santana/BA utilizados como camada de cobertura para aterro sanit?rio, utilizando os modelos de balan?o h?drico de Fenn et al. (1975) e S?o Mateus et al. (2012). Os resultados mostraram que, pelo m?todo de Fenn et al. (1975), ambos os materiais possuem comportamento semelhante, sendo que o RCC infiltrou menor quantidade de ?gua para o res?duo s?lido urbano (RSU) do que o solo. Pelo m?todo de S?o Mateus et al. (2012), o RCC e o solo permitem a passagem de ?gua para o RSU em comportamentos distintos, sendo que o solo promoveu maior infiltra??o de l?quidos, cerca de 95,5% maior do que o RCC. Quando comparados os m?todos, S?o Mateus et al. (2012) apresentou maior infiltra??o de ?gua para o RSU na simula??o com o solo, com rela??o ao m?todo de Fenn et al. (1975), e menor com o RCC, isto ocorre devido ? distin??o dos par?metros de entrada para os materiais, destacando-se a influ?ncia do coeficiente de permeabilidade no balan?o h?drico.
5

Avaliação de emissões fugitivas de biogás na camada de cobertura do aterro sanitário da CTR de Nova Iguaçu e do Lixão de Seropédica, Rio de Janeiro. / Monitoring and evaluation of biogas emission through the final cover layer of the waste treatment center of Nova Iguaçu and Dump of Seropédica, Rio de Janeiro.

Ana Carolina Eugênio de Oliveira 17 April 2013 (has links)
No Brasil, se espera ter até 2014, de acordo com o prazo da Política Nacional de Resíduos Sólidos, todos os lixões erradicados e os resíduos sólidos urbanos gerados depositados em aterros sanitários. Atualmente, os projetos de aterros sanitários dão oportunidade para um nicho de mercado, o da fonte de geração de energia. Um parâmetro de controle da poluição do ar causada pelos aterros sanitários são as chamadas camadas de cobertura. Nesse contexto, é de fundamental importância o estudo de camadas de cobertura de resíduos por ser um importante elemento de projeto para evitar ou minimizar a poluição do ar devido aos gases gerados em aterros sanitários de resíduos sólidos, já que é o elo existente entre o ambiente interno dos resíduos e a atmosfera. A presente pesquisa aborda o comportamento dos gases em relação à camada de cobertura existentes na CTR de Nova Iguaçu e no Lixão remediado de Seropédica. Foram realizados ensaios de Placa de Fluxo, medição de pressão e concentração dos gases no contato solo-resíduo e emissões dos gases pelos drenos, além das análises de solo in situ e em laboratório. Os ensaios foram realizados de outubro a novembro de 2012. Os resultados indicaram uma inexistência de fluxo de gases pela camada de cobertura, que possui 1,10 m de espessura, do lixão de Seropédica, sendo encontrado apenas fluxo nos drenos. Na CTR Nova Iguaçu, foi verificada que praticamente a inexistência de fluxo de gases com o sistema de gás ligado, mesmo possuindo uma camada de cobertura de 0,8 m. / In Brazil, according to the timeframe given by the National Policy of Solid Waste, by 2014, every dump will be eradicated and every municipal solid waste generated will be deposited in landfills. Currently, the landfill projects provide an opportunity for the market, which is a source of energy. A parameter of control of the air pollution caused by landfills is called cover layers. In this context, it is important the study of the cover layers to avoid or minimized the air pollution due to gases generated in landfills, which is the link between the solid waste and the atmosphere. This research addresses the behavior of the gases in relation to the cover layers on the CTR Nova Iguaçu and Dump of Seropédica. Six test trials of the Flux chamber, pressure measurement and concentration of gases in the soil-residue contact and emissions of gases through the drains, in addition to in situ soil analysis and laboratory analysis. The tests trials were performed from October, 2012 to November, 2012. The results indicated no gas flow through the cover layer, which has a thickness of 1.10 m, of the dump of Seropédica, where the gas flow was only encountered through the drains. In CTR Nova Iguaçu, the gas flow was almost inexistent, even having a cover layer of thickness of 0.8 m.
6

Avaliação de emissões fugitivas de biogás na camada de cobertura do aterro sanitário da CTR de Nova Iguaçu e do Lixão de Seropédica, Rio de Janeiro. / Monitoring and evaluation of biogas emission through the final cover layer of the waste treatment center of Nova Iguaçu and Dump of Seropédica, Rio de Janeiro.

Ana Carolina Eugênio de Oliveira 17 April 2013 (has links)
No Brasil, se espera ter até 2014, de acordo com o prazo da Política Nacional de Resíduos Sólidos, todos os lixões erradicados e os resíduos sólidos urbanos gerados depositados em aterros sanitários. Atualmente, os projetos de aterros sanitários dão oportunidade para um nicho de mercado, o da fonte de geração de energia. Um parâmetro de controle da poluição do ar causada pelos aterros sanitários são as chamadas camadas de cobertura. Nesse contexto, é de fundamental importância o estudo de camadas de cobertura de resíduos por ser um importante elemento de projeto para evitar ou minimizar a poluição do ar devido aos gases gerados em aterros sanitários de resíduos sólidos, já que é o elo existente entre o ambiente interno dos resíduos e a atmosfera. A presente pesquisa aborda o comportamento dos gases em relação à camada de cobertura existentes na CTR de Nova Iguaçu e no Lixão remediado de Seropédica. Foram realizados ensaios de Placa de Fluxo, medição de pressão e concentração dos gases no contato solo-resíduo e emissões dos gases pelos drenos, além das análises de solo in situ e em laboratório. Os ensaios foram realizados de outubro a novembro de 2012. Os resultados indicaram uma inexistência de fluxo de gases pela camada de cobertura, que possui 1,10 m de espessura, do lixão de Seropédica, sendo encontrado apenas fluxo nos drenos. Na CTR Nova Iguaçu, foi verificada que praticamente a inexistência de fluxo de gases com o sistema de gás ligado, mesmo possuindo uma camada de cobertura de 0,8 m. / In Brazil, according to the timeframe given by the National Policy of Solid Waste, by 2014, every dump will be eradicated and every municipal solid waste generated will be deposited in landfills. Currently, the landfill projects provide an opportunity for the market, which is a source of energy. A parameter of control of the air pollution caused by landfills is called cover layers. In this context, it is important the study of the cover layers to avoid or minimized the air pollution due to gases generated in landfills, which is the link between the solid waste and the atmosphere. This research addresses the behavior of the gases in relation to the cover layers on the CTR Nova Iguaçu and Dump of Seropédica. Six test trials of the Flux chamber, pressure measurement and concentration of gases in the soil-residue contact and emissions of gases through the drains, in addition to in situ soil analysis and laboratory analysis. The tests trials were performed from October, 2012 to November, 2012. The results indicated no gas flow through the cover layer, which has a thickness of 1.10 m, of the dump of Seropédica, where the gas flow was only encountered through the drains. In CTR Nova Iguaçu, the gas flow was almost inexistent, even having a cover layer of thickness of 0.8 m.
7

Análise do desempenho de um solo compactado utilizado na camada de cobertura de um aterro sanitário.

ARAUJO, Pabllo da Silva. 12 April 2018 (has links)
Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-04-12T20:13:37Z No. of bitstreams: 1 PABLLO DA SILVA ARAUJO – DISSERTAÇÃO (PPGECA) 2017.pdf: 6927035 bytes, checksum: 9da5e680617a44b7eff618d9c75ffcf3 (MD5) / Made available in DSpace on 2018-04-12T20:13:37Z (GMT). No. of bitstreams: 1 PABLLO DA SILVA ARAUJO – DISSERTAÇÃO (PPGECA) 2017.pdf: 6927035 bytes, checksum: 9da5e680617a44b7eff618d9c75ffcf3 (MD5) Previous issue date: 2017-03-29 / Capes / Uma das formas de tratamento de Resíduos Sólidos Urbanos (RSU) que mais se destaca são os aterros sanitários, que possui como vantagens, a facilidade de operação, menor custo quando comparado às outras técnicas (triagem, tratamento biológico, incineração, entre outras) e a existência de um plano de monitoramento contínuo. O aterro sanitário utiliza uma camada de cobertura final de solo compactado com a finalidade de isolar os resíduos do meio externo, minimizar a entrada de água para o interior do maciço sanitário, reduzir as emissões de gases para a atmosfera, evitar a proliferação de roedores e vetores de doença, entre outras. As Normas Brasileiras não regulamentam o tipo de solo a ser utilizado, nem técnicas de execução de camadas de coberturas de aterros, nem a forma de monitoramento, possuindo como única exigência o atendimento de um coeficiente mínimo de permeabilidade à água. Diante disso, este trabalho tem como objetivo analisar o desempenho do solo compactado utilizado na camada de cobertura final de um aterro de resíduos sólidos, tendo como campo experimental o Aterro Sanitário de Campina Grande/PB. Para isso foi realizada a caracterização física do solo utilizado na camada, verificação de seus parâmetros quanto à viabilidade para uso em aterros sanitários, análise físico-química e mineralógica, obtenção da curva de retenção de água no solo e análise dos pontos experimentais da curva aos ajustes propostos na literatura. Foi verificado o comportamento do solo frente aos processos de umedecimento/secagem e expansão/contração, observação da relação entre a umidade ótima de compactação e o ponto de entrada generalizada de ar (GAE), além da verificação da variação da umidade do solo em um perfil experimental da camada de cobertura por meio de sensores capacitivos. Os resultados demonstraram que, o solo possui permeabilidade à água admissível para uso em aterros sanitários segundo as normas nacionais e internacionais. O ajuste da curva de Van Genuchten aos pontos experimentais da curva de retenção atendeu às condições de concordância a partir dos parâmetros estatísticos analisados. A umidade ótima de compactação do solo possui valor próximo ao GAE, onde se inicia a dessaturação do solo, no qual o ar começa a entrar nos maiores poros formados pela drenagem da água e perda de umidade. Deve-se realizar a compactação do solo na energia proctor normal obedecendo à adição de água suficiente para atingir a umidade ótima, em um intervalo aceitável de ± 2%. Pode-se concluir que, o tipo de camada de cobertura final (solo argiloso compactado) utilizado é inadequado para a região do aterro devido às características climatológicas a que o solo está submetido e a ausência de proteção vegetal superficial. A aplicação da energia proctor normal para compactação do solo da camada de cobertura do aterro sanitário proporciona condições favoráveis à redução da permeabilidade à água do solo. A curva de retenção de água no solo da camada de cobertura do aterro sanitário apresenta comportamento unimodal e possui características de um solo argiloso. A utilização de sensores capacitivos se mostrou como uma técnica eficaz para aquisição automática da umidade do solo e verificação da sua variação ao longo do tempo, bem como, o monitoramento da sucção pela espessura da camada de cobertura final de solo compactado. / One of the forms of treatment of Municipal Solid Waste (MSW) is the landfill, which has the advantages of ease of operation, lower cost when compared to other techniques (sorting, biological treatment, incineration, among others) and the existence of a continuous monitoring plan. The landfill uses a final cover layer of compacted soil to isolate residues from the external environment, minimize the entry of water into the landfill, reduce the emission of gases into the atmosphere, prevent the proliferation of rodent and vectors of disease, among others. The Brazilian Regulations do not regulate the type of soil to be used, nor techniques for implementing layers of landfills, nor the form of monitoring, having as sole requirement the attendance of a minimum coefficient of water permeability. The objective of this work is to analyze the performance of the compacted soil used in the final cover layer of a landfill, with the Landfill Campina Grande/PB as an experimental field. The physical characterization of the soil used in the layer, verification of its parameters regarding the feasibility for use in landfills, physical-chemical and mineralogical analysis, obtaining the water retention curve in the soil and analysis of the experimental points of the curve were performed adjustments proposed in the literature. The behavior of the soil was verified in relation to the wetting/drying and swell/contraction processes, observation of the relation between the optimum compaction humidity and the Generalized Air Entry (GAE), besides the verification of soil moisture variation in one experimental profile of the cover layer by means of capacitive sensors. The results showed that the soil has permeability to water admissible for use in landfills according to national and international standards. The adjustment of the Van Genuchten curve to the experimental points of the retention curve met the conditions of agreement from the statistical parameters analyzed. The optimum soil compaction humidity has a value close to GAE, where soil desaturation begins, in which the air begins to enter the larger pores formed by water drainage and moisture loss. Soil compaction must be carried out in normal proctor energy by adding sufficient water to achieve optimum moisture, within an acceptable range of ± 2%. It can be concluded that the type of final cover layer (compacted clay soil) used is unsuitable for the landfill region due to the climatological characteristics to which the soil is subjected and the absence of surface vegetation protection. The application of normal proctor energy to soil compaction of the landfill cover layer provides favorable conditions for the reduction of soil water permeability. The water retention curve in the soil of the final cover layer of the landfill presents unimodal behavior and has characteristics of a clay soil. The use of capacitive sensors proved to be an effective technique for automatic acquisition of soil moisture and verification of its variation over time, as well as the monitoring of suction by the thickness of the final cover layer of compacted soil.
8

Možnosti využití různých druhů popílků při výrobě oxidovaných asfaltových izolačních pásů / Possibilities of utilisation different types of fly ashes in the production of oxidized asphalt insulation strips

Sklenářová, Radka January 2019 (has links)
Reducing the impact of modern industrial production on the environment and reducing the waste generated is undoubtedly one of the most discussed topics of the present time. In the production of fossil-fueled electricity, a large amount of fine-grained waste fly ash is generated. The possible use of ash as secondary raw materials in the construction and building materials industry is one of the many environmental challenges that the energy industry is concerned with. The aim of this diploma thesis was to verify possibilities of utilization of different kinds of power station fly ash as filler in asphalt mixtures for the production of oxidized asphalt insulation strips. The main emphasis was put on the clarification of the influence of the properties of the different types of fly ashes on the resulting rheological behavior of the mixture of asphalt binder and power fly ash, which is professionally called mastic. Mastic forms a technology-critical insulating layer in the asphalt insulation strip. The prediction of the rheological properties and therefore the workability of mastic appears to be an essential element in the management of production, especially under the conditions of the variability of input raw materials. In order to solve the assigned task it was necessary to perform detailed analyzes of fly ash properties, to select the corresponding quantification variable for assessment of the mastic processability and to find the signal fly ash properties, which appears to be a control parameter of workability. As a suitable method for assessing the processability of mastic, a shear viscosity measurement method was chosen. On the basis of the findings, it is possible to state that the use of fly ash from the production of oxidized asphalt bands is not recommended as the mastic prepared from these fly ashes are unprocessed at the assumed concentrations. The negative effect of fly ash after denitrification on the mastic processability has not been demonstrated.

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