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O objetivo do presente estudo foi caracterizar tecnologicamente painéis particulados produzidos com resíduo de beneficiamento de cinco espécies tropicais comerciais: angelim (Hymenolobium sp. / Andira sp.), cambará (Qualea sp.), canelão (Nectandra sp. / Ocotea sp.), cedro (Cedrelinga cateniformis) e itaúba (Mezilaurus itauba). Foram confeccionados três painéis de cada espécie, além de três painéis com a mistura das cinco espécies em iguais proporções (mix), totalizando 18 painéis com massa específica nominal de 0,65 g/cm³. Os painéis foram compostos por 12% de resina ureia formaldeído e 1% de emulsão de parafina. O ciclo de prensa utilizado foi de 160°C de temperatura, pressão de 40 kgf/cm² durante 8 minutos. Os dados foram submetidos à análise de variância e teste de Tukey a 95% de confiabilidade. Todas as madeiras, exceto o cedro, apresentaram massas específicas maiores e razões de compactação menores que o intervalo proposto pela literatura, o que refletiu em valores baixos de resistência e rigidez. Todos os painéis apresentaram resultados satisfatórios quanto à estabilidade dimensional dos painéis. As madeiras de angelim, cambará e canelão apresentaram resultados promissores. O cedro, apesar de resultar na maior razão de compactação, não apresentou resultados mecânicos na mesma magnitude, exceto para ligação interna. Recomenda-se a incorporação de espécies com menor massa específica básica, bem como o controle da granulometria das partículas e o aumento da massa específica nominal dos painéis. Palavras-chave: espécies alternativas, uso de resíduos, painéis de média densidade.

The objectives of this study were to evaluate the thermal comfort and the similitude between prototypes and reduced models, using non-conventional coverage with green roof and expanded clay aggregate, supported on wood frame structure. For this, were determined the Black Globe Temperature and Humidity Index (BGHI), the Human Discomfort Index (HDI), Effective Temperature (ET), Air Temperature (Tair) and Radiant Thermal Load (RTL), from March 2013 to December 2014. The results showed that there were no statistical differences to 5% significance in predicting heat indices between the prototypes and models. Observing all indexes simultaneously, it was observed that January was the month what led to the worst heat conditions, while June and July showed the worst cold conditions. It can be concluded that the use of reduced models is possible (1:2) compared to the prototype (1:1), with green roofs and expanded clay as covering element, for the prediction of thermal indexes, minimizing construction costs and use of spaces.

In the production of glue-laminated timber (GLT), boards derived from planted forest wood with easy workability are glued on top of one another. The main objective of the present work was to evaluate the performance of paricá timber GLT beams (5 × 10 cm) on GLT. Three procedures were performed: (1) GLT beams (5 × 10 cm) were produced using natural lamellae without chemical preservatives; (2) the individual lamellae (2.5 × 5 cm) were chemically treated, and then glued together; and (3) the beams formed from the glued natural lamellae (5 × 10 cm) were treated chemically. The positions of lamellae on the beams were determined by their modulus of elasticity values (MOE), which were estimated by a non-destructive bending test with a three-point load. The analytical bends, determined by the homogenized section method, and the experimental bends, measured by the four-point bending test, were compared. The differences between the bends were statistically evaluated, and it was found that the experimental bend (21.65 mm) was less than the analytical bend (34.02 mm). There was no significant loss of shear strength or MOE. The axial strength of the chemically untreated beams (49.18 MPa) was significantly higher than that of the untreated beams fabricated from natural lamellae (40.48 MPa). The results indicate that the gluing of treated lamellae does not affect beam performance.

This research was conducted with the objective of evaluating the thermal inertia and hysteresis of the following materials in a wind tunnel: hollow copper sphere with 150.0 mm diameter used as standard in globe thermometers, hollow brass sphere with 75.0 mm diameter, and two hollow plastic spheres with 115.5 and 69.7 mm diameter. The results showed that the thermal inertia and hysteresis for the hollow copper sphere were approximately 24 and 28 min, respectively; these values were bigger than those obtained for the other spheres, implying faster responses of these. While there were no statistical differences in the measurements conducted by globe thermometers which are used to indicate the black globe temperature with the different types of spheres mentioned above under indoor environment conditions, i.e., with no wind and solar radiation, the wind causes faster cooling in smaller spheres under outdoor environment conditions, which may denote erroneous interpretations of the measurements at those instants. It was concluded that it is possible to replace the hollow copper sphere of diameter 150 mm by other types of spheres to measure the black globe temperature. However, this requires knowledge of the response times of the spheres as well as corrections to be made in the measurements with respect to the globe thermometer standard.

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RESUMO-A Madeira Laminada Colada-MLC é um produto inovador de alto valor agregado, porém ainda não participa de programas de qualidade a exemplo do Programa Nacional de Qualidade da Madeira-PNQM e Programa Brasileiro da Qualidade e Produtividade do Habitat-PBQP-H. O presente trabalho visou oportunizar maior visibilidade ao produto em MLC, aferir maior segurança na sua concepção e utilização, estimular a participação das empresas produtoras de MLC em programas nacionais de qualidade. Para tanto, foram realizadas pesquisas sobre os produtos ofertados pelas empresas brasileiras de MLC, visitas às indústrias, consultas às normas técnicas e resoluções do Instituto Nacional de Metrologia, Qualidade e Tecnologia-INMETRO. Com base nesse levantamento foi elaborada esta proposta de um programa de qualidade voltado para produtos em MLC de uso estrutural e não estrutural. A implantação desta proposta de programa de qualidade facilitará a obtenção de subsídios às empresas e estimulará o consumo de MLC no mercado da construção civil. Palavras-chave: mercado; padronização; madeira certificada; madeira laminada colada; certificação. ABSTRACT-The GLT is an innovative product with high added value, but it still does not participate in quality programs such as the National Quality Wood-PNQM, and the Brazilian Program of Quality and Productivity Habitat-PBQP-H). This work aimed to create opportunities for greater visibility to the MLC product, assess their safer design and use, encourage the participation of companies producing MLC in national quality programs. Thus, we conducted a research on the products offered by Brazilian companies MLC, visits to industries, consultations to technical standards and resolutions of the National Institute of Metrology, Quality and Technology-INMETRO. Based on this survey we designed a program focused on MLC quality products structural and non-structural use. The implementation of the proposed quality program will facilitate obtaining grants to businesses and stimulate the consumption of MLC in the construction market.

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