This research examined the influence of the compositions between coconut fiber (Cocos nucifera) and wood particles (Pinus taeda L. and Eucalyptus saligna) on physico-mechanical properties of homogeneous particleboards. The exploratory study was carried out under Tukey’s contrast test of means, at 5% significance level, with the following compositions: 100% coconut fiber (F100 P0 E0); 50% coconut fiber, 25% pine particles, and 25% eucalyptus particles (F50 P25 E25); and 50% of pine particles and 50% of eucalyptus particles (F0 P50 E50), with particle moisture content between 0% to 2% and 10%, in mass, of polyurethane-castor oil (PU-Castor) resin. Three panels were produced for each composition. The physico-mechanical properties such as density, moisture content, swelling in thickness after 24 h of immersion in water, perpendicular tensile strength, static bending strength, and modulus of elasticity were evaluated using standard methods. The results obtained indicated the potential for using coconut fiber for the production of homogeneous particleboards in view of the minimum criteria required by the normative documents, with emphasis on the physical property of swelling after 24 hours, which obtained a statistically equivalent average relative to the treatment that contained only wood particles.

<p class="Normal1">Atualmente a utilização de madeiras de florestas plantadas para fabricação de derivados vem crescendo, sendo as espécies <em>Hevea brasiliensis </em>e <em>Tectona grandis </em>alternativas devido à abrangência de seus reflorestamentos no Brasil. Considerando seus ciclos de produção em torno de 30 anos, essas espécies podem ser alternativas de matéria-prima para fabricação de derivados de madeira. O objetivo desse trabalho foi produzir painéis aglomerados utilizando as referidas espécies, aglutinando-as com adesivo poliuretano derivado do óleo de mamona. Os painéis foram avaliados de acordo com suas propriedades físico-mecânicas, com base na ABNT NBR 14810 - 1 e 2 e demais literaturas nacionais e internacionais. Foram considerados dois tratamentos empregando-se 10% e 5% de adesivo, ambos com mistura de 30% de seringueira e 70% de teca. Para cada tratamento foram produzidos três painéis e avaliados suas densidades, teor de umidade, inchamento em espessura, módulo de resistência à flexão estática, módulo de elasticidade e resistência à tração perpendicular. Os resultados obtidos evidenciaram potencialidades de uso das duas espécies de madeira para a produção de painéis aglomerados. Os painéis produzidos com 10% de adesivo apresentaram melhores resultados em comparação aos painéis com 5%, entretanto, o emprego de 5% de adesivo atende às exigências normativas brasileiras.</p>

This work describes proposed experimental methods for the characterization of concrete in fresh and hardened state, with the purpose of contributing to the experimental characterization of concrete. The main objective was to identify the rheological behavior of high performance (HP) and self-compacting (SC) concretes. Initially, a ordinary concrete composition was proposed, from which, silica fume (5, 10 and 15% in mass) and superplasticizer (0.6% in mass) were added to obtain HPC and SCC. Furthermore, for the self-compacting concretes, a modification in granular skeleton was proposed, with a reduction of total aggregate percentage by 22.73% in relation to the other compositions. The interference of these modifications was evaluated on the behavior of fresh concrete though the flow and slump test and hardened concrete through mechanical properties. The results showed that the modification in the granular skeleton of ordinary concrete contributed directly to the reduction of inertia factors of SCC, favoring the mobility conditions. For both self-compacting and high performance concretes, consistency and mechanical strength gain over ordinary concrete were influenced when the silica fume and superplasticizer concentration was increased, limiting your properties gains to these additions.

The society's development provides consequences such as the increasing generation of industrial waste. In the city of Franca, São Paulo's inland city, there are footwear industries that generate a large amount of leather waste during their production process. In most cases, there's no use of this waste and they're disposed of in landfills. A reuse alternative is the production of particleboards used in construction sectors. Therefore, one of the biggest challenges is the use of this leather waste adding value to the product and enabling the production of sustainable material. This work proposes the production of particleboards from Eucalyptus wood and leather fibers using castor oil polyurethane adhesive. In addition, the assessment of the leather fiber influence on modulus of rupture and elasticity obtained from a static bending test. The study investigated the proportion of 10%, 25% e 50% leather waste in relation to Eucalyptus particles and 10% castor oil polyurethane adhesive. The mechanical performance of the panels was evaluated based on ABNT NBR 14810-1 and 2 (2013;. The results allowed us to ascertain that the incorporation of 10% leather waste in particleboard rated them, according to NBR 14810-1 and 2 (2013; 2018), as structural panels of type P4 for use in dry conditions.

O crescimento do consumo humano tem causado inúmeros transtornos para o meio ambiente, inclusive pelo descarte inapropriado de materiais inorgânicos de longa vida útil. A incorporação de potenciais resíduos na fabricação de painéis aglomerados à base de madeira se apresenta como uma alternativa a essa problemática. Esta pesquisa teve por objetivo avaliar os efeitos da substituição parcial de partículas de madeira por partículas de poliestireno expandido aglutinados com poliuretano de mamona. As partículas de madeira (50% de Pinus + 50% de Eucalipto) foram substituídas por 25 e por 50% (em massa) de partículas de poliestireno expandido visando aprimorar as propriedades físicas e mecânicas de painéis fabricados com 5% de adesivo poliuretano à base de óleo de mamona. Os compósitos fabricados com 50% de partículas de poliestireno resultaram nos melhores valores das propriedades físicas e mecânicas avaliadas (ABNT NBR 14810 e EN 312), designando credibilidade à produção de painéis com a substituição parcial de partículas de madeira por partículas de poliestireno.