<p>  </p> <p>Concrete is the second most consumed material in the world after water and is an essential element of constructed infrastructure. Over 14 billion m3 of concrete are being produced annually, resulting in a serious impact on the environment. The production of cement, which is the main component of concrete, is responsible for 5 – 8 % of global CO2 emissions. As a result, several global initiatives have been undertaken to achieve carbon neutrality by 2050. This carbon neutrality target coincides with the Paris Agreement's goal to limit global warming to 1.5 °C. A well-known, and successful strategy to reduce CO2 emissions in the concrete industry is to use supplementary cementitious materials (SCMs) as a partial replacement for cement. However, it is projected that in 2030 the demand for two of the most commonly used SCMs, fly ash and slag cement, will exceed their supply. Using nontraditional and natural pozzolans (NNPs) can help to close this supply gap, but there is a lack of knowledge regarding the reactivity and long-term performance of these materials.</p> <p>The purpose of this research was to perform experiments on several NNPs, some of which can be supplied in commercially viable quantities with the objective of evaluating their performance in cementitious systems (mortars and concretes) with the goal of accurately assessing their potential for use as alternative SCMs. The mortar study was performed using a total of 11 different NNPs, belonging to 4 distinctive groups and distributed as follows: 3 from the group of calcined clays (CCs) - CC1, CC2, and CC3, 3 from the group of natural pozzolans (NPs) - NP1, NP2 and NP3, 2 from the group of fluidized bed combustion (FBCs) ashes - FBC1 and FBC2, and 3 from the group of bottom ashes (GBAs) - GBA1, GBA2, and GBA3.</p> <p>The concrete study was performed on 4 different materials, one from each of the previously mentioned groups. The materials selected for concrete study were the worst-performing members of each group, as determined by the analysis of the test results obtained from mortars. These included CC2, NP3, FBC1, and GBA3 materials. This approach was adopted under the assumption that achieving adequate concrete characteristics with lowest-quality materials will all but assure satisfactory performance of concretes with higher-quality materials. </p> <p>The findings generated from this research indicate that several of the NNPs used in this study present a viable alternative to traditional SCMs. As an example, out of the 11 NNPS, 9 were found to conform to the requirements of the ASTM C618-19, the standard specification currently used to assess the suitability of coal fly ash and raw or calcined natural pozzolans for use in concrete. Results obtained from tests performed on mortars demonstrated that, when used at the replacement level of 25%, all 11 NNPs produced mixtures with characteristics similar to those obtained from the plain cement (OPC) mortar. For that reason, this level of replacement was selected to prepare concrete specimens. The results collected from concrete specimens showed that, when compared to plain concrete, mixtures with all 4 NNPs attained comparable (or improved) mechanical (compressive and flexural strength), durability (freeze-thaw resistance), and transport (formation factor and rate of water absorption) properties. As in the case of traditional SCMs, the mixtures with NNPs were found to require extended curing times to fully realize their property-enhancing potential associated with pozzolanic reactions. Overall, the best performing materials were those from the CCs group, followed by those belonging to, respectively, NPs, GBAs, and FBCs groups. </p>

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Made available in DSpace on 2016-03-15T19:34:24Z (GMT). No. of bitstreams: 1 Leandro Moreira Valente Barbas.pdf: 3080773 bytes, checksum: 5224fe793510ae5cce0c2781893d8c66 (MD5) Previous issue date: 2015-08-05 / Fundo Mackenzie de Pesquisa / The scenario of tough competition, typical of any market economy, stimulates the creativity of its players when building brand identities. The search for signs that separate from the traditional model based on a visual static mark, classified as a sole design, word or mixed mark is increasingly common. Law cannot remain idle in witnessing this scenario, since those new distinctive signs have their own particularities that are not contemplated by the Brazilian Industrial Property Law. The protection of the consumer market, of free competition and even of the owners private property of the signs themselves depend necessarily on having clear answers from the Law regarding the issue. Otherwise, the trademark system may become unstable. Therefore, this work aims at defining basic concepts regarding the theme and analyzing the main legal issues related to nontraditional marks, having international experiences on the matter as a basis. / O cenário de acirrada competição típico de qualquer economia de mercado estimula a atividade criativa de seus participantes quando da construção de identidades marcárias. É cada vez mais constante e comum a busca por sinais que fogem ao modelo tradicional de marca visual estática, figurativa, mista ou nominativa. Estes sinais recebem o nome geral de marcas não tradicionais . O Direito não pode aí quedar-se inerte, uma vez que estes novos sinais distintivos têm peculiaridades próprias que fogem, em boa medida, à sistemática determinada pela Lei de Propriedade Industrial. Logo, a proteção do mercado consumidor, da livre concorrência e mesmo da propriedade privada dos titulares dos sinais passam necessariamente por uma obtenção de respostas claras do Direito neste tema, sob pena de instabilizar-se o sistema marcário. Esta obra tem o objetivo de delinear conceitos básicos sobre o tema das marcas não tradicionais e analisar as principais problemáticas jurídicas envolvidas, baseando-se em experiências internacionais na matéria.