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Improvement of the shear strength parameters of an expansive soil using recycled glass powder and polypropylene fibersMacHuca, Joao Rodriguez, Pusari Quispe, Oscar, Ramirez, Gary Duran, Fernandez Diaz, Carlos 30 September 2020 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / n this article, the geotechnical behavior of the reinforced soil is studied through additions of polypropylene fiber and recycled glass powder, this in order to obtain a homogeneously reinforced soil matrix to reduce possible structural failures, differential settlements and increase capacity bearing. The sample used was classified as a clay soil with low plasticity (CL) and with moderately expansive characteristics, based on the values of the Liquid Limit, Plastic Limit and Plasticity Index. The effect of the 1% polypropylene fiber and different amounts of recycled glass powder (0%, 4%, 5%, 6.5%), with respect to dry weight is analyzed in this soil. The purpose of varying the quantity of these materials is to find a trend of the strength parameters and obtain the optimal percentages that provides improvements in geotechnical behavior. Modified Proctor and Direct Shear tests were carried out, this latter to obtain the shear strength parameters of the mixtures and compare them with the clay soil. Finally, the optimal result for soil improvement was the mixture made by 1% polypropylene fiber and 4% glass powder, which achieved an increase of the angle of friction and cohesion.
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Recycled Aggregate & Robotic Contour CraftingCampbell, Andrew S. 25 June 2019 (has links)
No description available.
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Grout Impregnation Of Pre-Placed Recycled Concrete Pavement (Rcp) For Rapid Repair Of Deteriorated Portland Cement Concrete Airfield PavementsMann, Travis A 09 December 2006 (has links)
The U.S. military must have the ability to rapidly deploy troops and equipment anywhere in the world as part of a contingency operation. Recent military operations have highlighted the critical need for rapid repair procedures and materials for military use on sub-standard, in-theater airfields. The U.S. Army Corps of Engineers, Engineer Research and Development Center is currently addressing these problems through a program titled ?Joint Rapid Airfield Construction?. This study involves the development of a method using rapid setting grouts and recycled concrete pavement (RCP) to repair portland cement concrete (PCC) pavements. A laboratory study was conducted to evaluate material properties in order to gain an understanding of expected field performance. Eight full scale repairs were constructed using two rapid setting grouts, two types of equipment, and two concrete slabs. The repairs were successfully trafficked with simulated C-17 aircraft wheel loads to verify the structural capacity, and ultimately the procedures.
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The Role of Detritivorous Fish in Supporting New Phosphorus and Primary Production in Reservoir EcosystemsLaurich, Leah Marie 05 August 2005 (has links)
No description available.
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EVALUATION OF INTERLOCKING CONCRETE BLOCK PAVEMENT WITH RECYCLED MATERIALS BASED ON EXPERIMENTAL AND FINITE ELEMENT ANALYSISNi, Xinyue 11 1900 (has links)
To address the challenges associated with urban expansion and environmental changes, innovative interlocking concrete block pavement (ICBP) is being researched for usage in urban areas. The ICBP is designed to have higher durability and better long-term performance compared to traditional asphalt pavement. Using recycled concrete aggregates (RCA) and supplementary cementing materials (SCMs) can provide many environmental benefits. The objective of this research is to investigate the mechanical properties of concrete with recycled materials. This also involves the assessment of deflection and stresses associated with ICBP using the finite element method.
Four concrete mixtures with different RCA and SCMs contents were designed and cast. The RCA replacement levels were 20% and 40%, while slag and glass pozzolan were added to improve mechanical properties. The results showed that the use of RCA had adverse impacts on workability. The 28 days compressive strength of the Control Mix was 40 MPa. The compressive strength of Mix 3 was 40.5 MPa which was the highest strength among all mixtures. It demonstrated that a 40% RCA replacement level could have a non-negative effect on mechanical properties when the SCMs are added.
A three-dimensional pavement model was established using ABAQUS software. The orthogonal experimental design was used to evaluate the effects of the length/width ratio of blocks, the block thickness, the elastic modulus, and the laying pattern of blocks on the deflection and von Mises stress of all ICBP models under the vertical load. Considering the deflection of the loading area, the length/width ratio had the greatest effect, then comes with thickness, elastic modulus, and laying pattern according to the Range Analysis. The bigger block size and higher elastic modulus of blocks could provide even better performance. Overall, the herringbone laying pattern is recommended as the optimum laying pattern with minimum deflection. It also contributes to better load spreading. / Thesis / Master of Applied Science (MASc)
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Investigation of Testing Methods to Determine Long-Term Durability of Wisconsin Aggregate Resources Including Natural Materials, Industrial By-Products, and Recycled/Reclaimed MaterialsWilliamson, Gregory Scott 04 May 2005 (has links)
The Wisconsin Department of Transportation (WisDOT) uses approximately 11,000,000 tons of aggregate per year for transportation projects. Being able to select durable aggregates for use in transportation projects is of considerable importance, if the aggregate deteriorates then the constructed facility requires premature repair, rehabilitation or replacement. Realizing the importance and also that deficiencies in the current WisDOT testing protocol may exist, it has been concluded that the durability-testing program for Wisconsin aggregates needs to be updated. For example, WisDOT is currently using the Sodium Sulfate Soundness Test (ASTM C 88) to measure durability, a test that was put in place in 1960. The ability of this test to predict durability performance and simulate field conditions is questionable and it has also been criticized for its lack of precision.
It should also be noted that the use of recycled and reclaimed aggregates has increased in recent years and not all typical durability tests can be used for testing these aggregates. The Sulfate Test in particular cannot be used for testing Recycled Concrete Aggregates (RCA) because the chemical reaction produces erroneous and misleading results.
This project has identified recent advances in the understanding and testing of aggregate durability. An in depth literature review has been conducted and from the compiled information a laboratory testing program was developed. Selection of the tests was based upon the tests' precision, efficiency, and predictive capabilities. In the laboratory-testing phase of this project the proposed durability tests along with current WisDOT durability tests were used to evaluate the full range of Wisconsin aggregates.
From the test results it was found that the WisDOT aggregate testing protocol could be reduced substantially by eliminating many of the testing requirements for aggregates that have a vacuum saturated absorption of less than 2%. Also, the addition of several tests was ruled out due to their lack of correlation with field performance records. The Micro-Deval abrasion test is recommended for inclusion in WisDOT testing protocol as a test to measure the abrasion resistance of aggregate while the L.A. Abrasion test is better suited as a measure of aggregate strength. Additional conclusions were made based on the durability testing conducted and an overall testing protocol has been developed and is recommended for implementation by WisDOT. / Master of Science
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Effect of solid-state shear milled natural rubber particle size on the processing and dynamic vulcanization of recycled waste into thermoplastic vulcanizateInnes, James R., Shriky, Banah, Allan, S., Wang, X., Hebda, Michael J., Coates, Philip D., Whiteside, Benjamin R., Benkreira, Hadj, Caton-Rose, Philip D., Lu, C.H., Wang, Q., Kelly, Adrian L. 29 March 2022 (has links)
Yes / Natural rubber (NR) and crosslinked polyethylene (XLPE) waste streams were devulcanized by solid state shear milling (S3M), producing a fine powder that may be more easily reprocessed. Understanding devulcanization and the nature of decrosslinked thermoset materials is of utmost importance for turning these waste steams into functional products. It was found that the devulcanized powders contained significant concentrations of radicals, which may be active in the subsequent revulcanization process. The produced devulcanized powders were converted into recyclable thermoplastic vulcanizates (TPVs) by twin screw extrusion. Reprocessing of these powders into value-added products is an important step in recycling and the use of extrusion allows for high throughput and industrial viability. Herein, we demonstrate that the optimal conditions for reprocessing are dependent upon the particle size of the devulcanized powder. Furthermore, dynamic vulcanization is affected by the nature of these recyclate powders. The successfully prepared TPVs showed similar properties to virgin materials, with a high elongation to failure. Therefore, the conversion of waste rubber into the rubber phase of a TPV shows significant promise in moving towards sustainable products, providing the revulcanization step can be well controlled. / EPSRC and NSFC for their funding of this work through the Joint UK-China Low Carbon Manufacturing Grant, Grant number EP/S018573/1.
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Development of Concrete Mixtures Based Entirely on Construction and Demolition Waste and Assessment of Parameters Influencing the Compressive StrengthYildirim, Gurkan, Ozcelikci, E., Alhawat, Musab M., Ashour, Ashraf 22 March 2023 (has links)
Yes / Demolition and reconstruction of degrading structures alongside with the repetitive repair, maintenance, and renovation applications create significant amounts of construction and demolition waste (CDW), which needs proper tackling. The main emphasis of this study has therefore been placed on the development of concrete mixtures with components (i.e., aggregates and binder) coming entirely from CDW. As the binding phase, powdered CDW-based masonry units, concrete and glass were used collectively as precursors to obtain geopolymer binders, which were then incorporated with CDW-based fine and coarse concrete aggregates. Together with the entirely CDW-based concretes, designs were also proposed for companion mixtures with mainstream precursors (e.g., fly ash and slag) occupying some part of the CDW-based precursor combination. Sodium hydroxide (NaOH), sodium silicate (Na2SiO3) and calcium hydroxide (Ca[OH]2) were used at various concentrations and combinations as the alkaline activators. Several factors that have impact on the compressive strength results of concrete mixtures, such as mainstream precursor replacement rate, al-kaline molar concentrations, aggregate-to-binder ratios and curing conditions, were considered and these were also backed by the micro-structural analyses. Our results showed that through proper optimiza-tion of the design factors, it is possible to manufacture concrete mix-tures entirely out of CDW with compressive strength results able to reach up to 40 MPa under ambient curing. Current research is believed to be very likely to promote more innovative and up-to-date techniques to upcycle CDW, which are mostly downcycled through basic practices of road base/sub-base filling, encouraging further research and increas-ing the awareness in CDW issue.
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Placas recicladas de embalagens longa vida: caracterização, design e propostas projetuais / Recycled plates from cartoon packaging: characterization, design and project proposalsCunha, Érica Cristina 30 September 2011 (has links)
Esta tese apresenta o estudo das placas recicladas provenientes de embalagens Longa Vida. São compostas principalmente por polietileno de baixa densidade, alumínio e resíduos de papel. Embora as placas recicladas sejam tratadas como sustentáveis e aplicadas nas edificações com resultados positivos, são poucos os dados publicados que apresentam sua caracterização geral. Outros problemas foram identificados, como a necessidade de melhoria na tecnologia para produção, dificuldade na aceitação estética e pouco design incorporado aos produtos e objetos resultantes. Apesar dos problemas, a observação do uso crescente dessas placas resultou no traçado da hipótese desta pesquisa: as placas podem ser mais eficientes e atrativas para especificação, se utilizadas com design incorporado aos componentes arquitetônicos. A partir disso, o trabalho busca dois objetivos essenciais: traçar um perfil de caracterização técnica e de design relacionados ao material e, a partir desse repertório, apresentar propostas projetuais alternativas para uso na arquitetura. Para tanto, foram estudadas as conceituações sobre materialidade, as abordagens técnicas, estéticas e culturais e a reciclagem e produção das placas, além de ensaios térmicos de condutividade térmica e calor específico, absortância, envelhecimento acelerado em câmera de UV e o ensaio complementar de transição vítrea. A caracterização estética gerou dados sistematizados sobre textura, tamanho, espessura e estudos compositivos com outros materiais. Por fim, foram criadas três propostas projetuais como indicativos de novas possibilidades de uso das placas. Este estudo concluiu que as placas de polietileno-alumínio podem ser utilizadas em várias superfícies arquitetônicas, desde que cuidadosamente incorporadas aos sistemas, prezando-se a qualidade da produção, projeto, design e acabamento. / This thesis presents the study of plates from recycled cartoon packaging. They are composed mainly of low density polyethylene, aluminum and paper waste. Although the plates are treated as recycled and sustainable, applied in building with positive results, there are few published data to show their general characterization. Other problems were identified: need for improvement of production technology, difficulty in accepting some design aesthetics and few design incorporated to the products and the resulting objects. Despite the problems, the observation of the growing use of these plates resulted in the design of the hypothesis of this research: the plates can be more efficient and attractive to specification if used with design incorporated into the architectural components. Based on this, the work seeks two essential goals: a profile of technical characterization and design-related material, and from this repertoire, present proposals about design alternatives for use in architecture. To this end, were studied the concepts of materiality, in technical, aesthetics and cultural approaches and the recycling and production of plates, besides the thermal tests of thermal conductivity and specific heat, absorptance, accelerated aging and UV camera and additional test of glass transition. The aesthetic characterizations generated systematic data on texture, size, thickness and compositional studies with other materials. Finally, were created three project proposals as indicative of new possibilities to use the plates. Through this study it can be concluded that the polyethylene-aluminum plates can be used in various architectural surfaces, as long as they are carefully incorporated into the systems, maintaining the quality the quality of production, design and finish.
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Placas recicladas de embalagens longa vida: caracterização, design e propostas projetuais / Recycled plates from cartoon packaging: characterization, design and project proposalsÉrica Cristina Cunha 30 September 2011 (has links)
Esta tese apresenta o estudo das placas recicladas provenientes de embalagens Longa Vida. São compostas principalmente por polietileno de baixa densidade, alumínio e resíduos de papel. Embora as placas recicladas sejam tratadas como sustentáveis e aplicadas nas edificações com resultados positivos, são poucos os dados publicados que apresentam sua caracterização geral. Outros problemas foram identificados, como a necessidade de melhoria na tecnologia para produção, dificuldade na aceitação estética e pouco design incorporado aos produtos e objetos resultantes. Apesar dos problemas, a observação do uso crescente dessas placas resultou no traçado da hipótese desta pesquisa: as placas podem ser mais eficientes e atrativas para especificação, se utilizadas com design incorporado aos componentes arquitetônicos. A partir disso, o trabalho busca dois objetivos essenciais: traçar um perfil de caracterização técnica e de design relacionados ao material e, a partir desse repertório, apresentar propostas projetuais alternativas para uso na arquitetura. Para tanto, foram estudadas as conceituações sobre materialidade, as abordagens técnicas, estéticas e culturais e a reciclagem e produção das placas, além de ensaios térmicos de condutividade térmica e calor específico, absortância, envelhecimento acelerado em câmera de UV e o ensaio complementar de transição vítrea. A caracterização estética gerou dados sistematizados sobre textura, tamanho, espessura e estudos compositivos com outros materiais. Por fim, foram criadas três propostas projetuais como indicativos de novas possibilidades de uso das placas. Este estudo concluiu que as placas de polietileno-alumínio podem ser utilizadas em várias superfícies arquitetônicas, desde que cuidadosamente incorporadas aos sistemas, prezando-se a qualidade da produção, projeto, design e acabamento. / This thesis presents the study of plates from recycled cartoon packaging. They are composed mainly of low density polyethylene, aluminum and paper waste. Although the plates are treated as recycled and sustainable, applied in building with positive results, there are few published data to show their general characterization. Other problems were identified: need for improvement of production technology, difficulty in accepting some design aesthetics and few design incorporated to the products and the resulting objects. Despite the problems, the observation of the growing use of these plates resulted in the design of the hypothesis of this research: the plates can be more efficient and attractive to specification if used with design incorporated into the architectural components. Based on this, the work seeks two essential goals: a profile of technical characterization and design-related material, and from this repertoire, present proposals about design alternatives for use in architecture. To this end, were studied the concepts of materiality, in technical, aesthetics and cultural approaches and the recycling and production of plates, besides the thermal tests of thermal conductivity and specific heat, absorptance, accelerated aging and UV camera and additional test of glass transition. The aesthetic characterizations generated systematic data on texture, size, thickness and compositional studies with other materials. Finally, were created three project proposals as indicative of new possibilities to use the plates. Through this study it can be concluded that the polyethylene-aluminum plates can be used in various architectural surfaces, as long as they are carefully incorporated into the systems, maintaining the quality the quality of production, design and finish.
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