RESUMOO objetivo deste trabalho foi verificar a influência da adição de resíduos de poli (tereftalato de etileno) -PET -sobre a resistência mecânica em concreto de cimento Portland. O PET foi utilizado no formato encontrado em indústria de reciclagem de embalagens. Os resíduos foram utilizados como substitutos de parte dos agregados do concreto e, para cada um dos resíduos, foram preparados quatro traços (10%, 20%, 30% e 40%, em volume). Para a preparação dos traços foi utilizado cimento Portland de Alta Resistência Inicial (CPV -ARI) fornecido pela Votoran. A partir de cada uma das misturas obtidas foram confeccionados quinze corpos-de-prova em formato cilíndrico conforme a norma NBR 5738. Foram preparados também corpos-de-prova sem substituição de agregados que serviram como material de referência. Os ensaios de compressão foram realizados de acordo com a norma NBR 5739, nas idades de um, três e sete dias e, em cada uma destas idades, foram testados cinco corpos-de-prova de cada traço. Para todos os traços obtidos e, em todas as idades das amostras ensaiadas, pode-se notar uma tendência de redução da resistência mecânica com o aumento da fração volumétrica de substituição de agregados. O maior valor de resistência à compressão axial com a idade de sete dias foi apresentado pelo traço sem substituição de agregados (15,38 MPa), e o menor valor, para a mesma idade, foi apresentado pelo traço com 40 % de substituição de agregados por resíduos de PET (1,94 MPa).Palavras-chaves: concreto, cimento Portland, resíduos, poli (tereftalato de etileno) -PET. Evaluation of concrete made of Portland cement containing PET wastes ABSTRACTThis work aims to verify the influence of poly (ethylene terephthalate) -PET -wastes additions on the concrete mechanical strength. The concrete used was prepared with a Portland cement. The PET was used in the as received shape from the packing recycling industry. The wastes were used as substitutes of concrete aggregates. For each waste type four mixtures (10, 20, 30 and 40 vol-%) were prepared. In order to prepare mixtures, high early strength Portland cement (CPV -ARI) was used, supplied by the Votoran Company. From each mixture obtained fifteen cylindrical shaped samples were prepared. The samples were prepared in accordance to the NBR 5738 Brazilian Standard. As reference materials, samples without wastes were also prepared. Mechanical strength tests were performed according to the Brazilian Standard NBR 5739. In this case, the following ages were tested: one, three and seven days. For each age, five samples were tested from each mixture prepared. For all mixtures obtained and for each sample age tested, a reduction in the mechanical strength occurred as the PET waste additions were increased. The highest mechanical strength value, 15.38 MPa, was obtained using sample with seven days age and mixture without aggregates. The lowest strength value, 1.94 MPa, was also obtained using sample with seven days age but with 40 vol-% PET waste addition.
comparing scenarios with 10%, 15% and 20% of biodiesel in this composition. This comparison was carried out by means of simulation of a computational model developed by the researchers based on the methodology proposed by Sterman (2000). In the definition of the equations and their relations of the simulation model, a time horizon of ten years was considered. The results show that, from a financial perspective, there is a great difference between the different percentages of biodiesel in fuel composition, showing advantages in the use of biodiesel with higher percentage.
O processamento de dados georreferenciados obtidos a partir de Veículos Aéreos Não Tripulados (VANT’s) requer técnicas e ferramentas específicas, visando produzir informações adequadas para as mais diversas finalidades. O surgimento recente de diferentes ferramentas para esse tipo de manipulação de dados torna esse processo mais acessível e flexível. Neste sentido, o presente trabalho realiza um estudo comparativo entre ferramentas de software de processamento de dados georreferenciados para manipulação e tratamento de dados e imagens coletados com o uso de VANT’s. Este trabalho apresenta algumas ferramentas atualmente disponíveis, detalhando suas principais características de modo a orientar futuros usuários na escolha do software conforme suas necessidades. Foram testadas as ferramentas Drone Deploy, Pix4DMapper, Agisoft e Photomodeler, e os aspectos tempo de processamento, geração de ortofoto, possibilidade de trabalho offline e custo de licença. As ferramentas analisadas possuem recursos semelhantes, mas com diferentes aspectos operacionais que podem ser determinantes para a escolha do usuário.
Purpose – This paper aims to compare rail and road modes of transport to carry Municipal Solid Waste using a simulation based on the Systems Dynamics of the financial and environmental differences between both. Design/methodology/approach – For modeling, the methodology proposed by Law (2015) based on Systems Dynamics was adopted. As such, the Systems Dynamics methodology helped to map structures for the system developed, seeking to examine its interrelation in a broad context. Through this simulation, the applied dynamics sought to understand how the system in question evolved over time and how changes in its parts affect its behavior. From this understanding, the system could be diagnosed and predicted, in addition to allowing more scenarios to be simulated over time. The time horizon used was eleven years. Findings – The findings show that, as seen from a financial perspective, there is a large difference between road and rail modes of transport to carry MSW. Therefore, it demonstrates the importance of valuing the railroads, in addition to being another option for managers to collect and transport waste generated in the municipalities studied. Originality/value – The model developed can be used by managers in the area of Municipal Solid Waste as a focus to help in the decision-making process to choose logistical options to transport waste. Keywords – Municipal Solid Waste; Modes of Transport; Systems Dynamics; Rail, Road.
This paper presents a computer simulation model to analyze energy saving in waste recycling. This simulation aims to support environmental decision-making process especially in regards to issues as agenda setting for Environmental Policy and its evaluation. The proposed model is based on the following parameters: population growth rate, solid waste and recycling rates, gravimetric composition of the material in the total waste generated, Per capita waste generation and, electrical energy saving materials. . For modeling and system implementation the Vensim software from Ventana Systems was used. Through the results generated by the model, it is expected that environmental managers will be able to, for example, set incentives to reduce the total generation of waste and produce campaigns emphasizing reuse and recycling. Model validation was made through the analysis of future scenarios for a given city in southern Brazil.
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