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The objective of this work is to show the effect of carbonation at early stages on fiber-cement composites and impact on hydration, chemical and dimension stability. Carbonation increased the content of CaCO 3 polymorphs and consumed Ca(OH) 2 and other hydrated calcium phases. Micrographs and energydispersive spectrometry showed the CaCO 3 formed is precipitated in the pore structure of the matrix, decreasing diffusion of Si, S, and Al during hydration. Therefore, a refining process of pore sizes is produced, and fiber-matrix interface in carbonated composites was improved, leading to volume stabilization of the composite, as indicated by lower drying shrinkage and lower porosity.

This work aimed to investigate the feasibility of using and mixing Toona ciliata, Eucalyptus grandis/ urophylla and Pinus oocarpa woods in OSB production. Three one-species and four mixed-species combinations were compared. Layer structure varied by positioning different wood species in the surface and core of the panels. Phenol-formaldehyde (PF) adhesive was applied at 9% for all OSB panels. Three-layer mats with mass proportion of 25/50/25% for surface/core/surface were produced. Pressing time was 8 min, under a 4 MPa pressure and temperature of 180 ˚C. Physical and mechanical properties were evaluated and compared to EN (300) commercialization standard. Most OSB panels did not fully attain such requirements. OSB panels made with Eucalyptus grandis/urophylla and Pinus oocarpa woods have potential to be commercialized as OSB/1 and OSB/2 types, respectively. Among panels made with T. ciliata wood, those produced with this species in the surface and Eucalyptus grandis/urophylla wood in the core met the requirements established for OSB/1 commercialization. Eucalyptus wood has great potential to substitute Pinus wood in OSB production. The utilization of T. ciliata wood for OSB production decreased mechanical performance, but remarkably enhanced water resistance properties.

A análise ergonômica do trabalho visa avaliar, diagnosticar e corrigir uma situação real de um posto de trabalho, proporcionando ao operador melhores condições de trabalho e produtividade. Este trabalho objetivou avaliar o ambiente de trabalho em uma serraria no município de Jerônimo Monteiro-ES, visando à melhoria da saúde, do bem-estar, da segurança e da produtividade dos trabalhadores. Na serraria, determinou-se o nível de ruído por meio de dosímetros e decibelímetro; a iluminação, com auxílio de luxímetro e fotocélula, e o conforto térmico, com base nas médias de temperaturas registradas pelo Índice de Bulbo Úmido e o Termômetro de Globo (IBUTG). Os dados mostraram que o nível de ruído é inaceitável, assim como o sistema de iluminação é inadequado para tal atividade produtiva. O conforto térmico atendeu as conformidades da norma. Assim, é fundamental alterar o sistema de iluminação, utilizando melhor a iluminação natural e reestruturando a iluminação geral e específica nos equipamentos; faz-se também necessário promover o uso de protetores auriculares e instalar dispositivos que minimizem a emissão de ruídos nas máquinas.