Mestrado em Ciências Florestais

URI Permanente para esta coleção

http://repositorio.ufes.br/handle/10/17467

Nível: Mestrado Acadêmico
Ano de início: 2008
Conceito atual na CAPES: 4
Ato normativo: Ofício N. 39-12/2007/CTC/CCA/CAPES de 31/07/2007 Homologado pelo CNE (Portaria Nº 656 de 22/05/2017) Publicação DOU em 27/07/2017, Seç. 1, Pag. 36.
Periodicidade de seleção: Semestral
Área(s) de concentração: Ciências Florestais
Url do curso: https://cienciasflorestais.ufes.br/pt-br/pos-graduacao/PPGCFL/detalhes-do-curso?id=1424

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    Caracterização do bambu laminado colado como alternativa tecnológica industrial
    (Universidade Federal do Espírito Santo, 2013-07-30) Rosa, Rafael Amorim; Segundinho, Pedro Gutemberg de Alcântara; Vidaurre, Graziela Baptista; Paes, Juarez Benigno; Oliveira, Ana Karla Freire de; Gonçalves, Fabrício Gomes
    This study aimed to verify the technological properties of the Dendrocalamus giganteus and Bambusa vulgaris bamboo; evaluate the physical and mechanical properties of glued laminated bamboo (BLC) according to the species, the adhesives and the preservant treatments; correlate both the module break and the modulus of elasticity - MOE of BLCs obtained by means of nondestructive methods with destructive method.. For this, were produced bamboo slivers with dimensions 0,5 x 3,0 x 70,0 cm (thickness, width and lenght) with B.vulgaris and D. giganteus species over three years old. One of these bamboo slivers were immersed in water and the other part in Timbor, lasting 15 days for both treatments. The adhesives used were based emulsion polymer isocyanate (EPI), melamine urea formaldehyde (MUF); cross polyvinyl acetate (PVAc) and resorcinol formaldehyde (RF). The non-destructive methods were used Stress Wave (SW), longitudinal vibration (vib. long.) and transverse vibration (vib. trans.). It was observed that the BLCs made from B. vulgaris demonstrated greater dimensional instability than those produced with the D. giganteus. However, MUF adhesive and RF conferred greater dimensional stability for the BLCs produced with both species. Both BLCs D. giganteus and B. vulgaris in relation to the two treatments had the lowest average failure in bamboo bonded with EPI and PVA. For BLCs produced from D. giganteus bamboo, the Stress Wave method proved not to be suitable for estimating the elastic modulus to BLCs adhered with EPI, MUF, PVA and RF. The vib. Long. and vib. trans. Methods demonstrated good possibility of estimating the MOE for BLCs of D. giganteus for any adhesive. For non-destructive methods performed with BLCs B. vulgaris bamboo, Stress Wave technique proved to be suitable for the BLCs bonded with MUF and PVA. In the vib. Long. Method, the BLCs made from B. vulgaris and bonded with MUF, PVA and RF had high estimation error. Already vib.trans.method provided high coefficient of Pearson correlation (R²), proving to be the most recommended. The vib.trans.method proved to be the best in the estimation of the modulus of elasticity for both BLCs made from D. giganteus and B. vulgaris, providing the smallest errors and the highest R². According to the physical and mechanical results obtained, it can be affirmed that BLCs made with both the species of D. giganteus or B. vulgaris may be employed for the furniture production
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    Desempenho da madeira laminada colada de eucalipto
    (Universidade Federal do Espírito Santo, 2018-02-27) Oliveira, Rafael Gonçalves Espósito de; Segundinho, Pedro Gutemberg de Alcântara; Gonçalves, Fabricio Gomes; Oliveira, José Tarcísio da Silva; Oliveira, Michel Picanço; Azevedo, Macksuel Soares de
    The objectives of this work were to produce bonded laminated wood (MLC) elements from the wood of Eucalyptus grandis x E. urophylla clones and to evaluate their behavior when submitted to the normal compression stress to the fibers. For the production of bonded laminated wood (MLC), the wood was classified based on the apparent density of the boards, in two groups (1: <0.587 g / cm3, 2: = 0.587 g / cm3). The MLC elements were glued with two adhesives, resorcinol-formaldehyde, "Cascophen", and another, a bi-component, castor-based polyurethane adhesive. The moisture content of the boards, the apparent density and the shrinkability, and mechanical tests of normal compression to the fibers, parallel shear to the fibers, shear in the glue line and delamination were determined. For anatomical characterization and collage quality evaluation, histological slides were prepared to visualize the anatomical elements of the species and to measure the glue line. It was observed that the evaluated wood presented satisfactory results to be used in the manufacture of MLC, especially in those boards of higher apparent density and bonded with the resorcinol-formaldehyde adhesive, with higher values for the mechanical stresses evaluated. The higher density boards presented vessels with larger diameters, high and wide radii, making the structure propitious for mobility and penetration of the adhesive. The density showed a correlation with the mechanical properties, the thickness of the main glue line showed correlation with the adhesive and with the percentage of failure in the wood, the adhesive also presented correlation with the percentage of wood failure. The normal fiber compression showed a correlation with the shearings parallel to the fibers and in the glue line. The latter showed a correlation with the apparent density, adhesive, secondary glue line and vessel diameter. The shear parallel to the fibers showed a correlation with the shear strength in the glue line and the vessel diameters. The height and width of the rays had a correlation with the number of cells.
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    Desenvolvimento de calços de madeira laminada colada a partir de resíduos de eucalipto
    (Universidade Federal do Espírito Santo, 2019-02-27) Lopes, Nayara Franzini; Gonçalves, Fabricio Gomes; Pedro Gutemberg de Alcântara Segundinho; Alves, Rejane Costa; Oliveira, José Tarcísio de Silva
    Timber dunnage are used as separators between steel plate and metal profiles in the stowage and storage and are currently made up of pieces of solid sawn timber. However, the reduction of the offer of native species wood to and the inability of the reforestation species to provide pieces of wood with good quality to the market led to the use of alternative techniques for better use of wood. Then there is the technique of glued laminated timber (Glulam) which is the gluing of woods from the association of pieces that are selected and arranged with the fibers parallel to each other for gluing using adhesives and pressing, that can to substitute the solid wood. It is known that this technique has a relevant appeal in terms of the potential of use already established in wood structures. So, this work aimed to develop a type of dunnage with the use of the technology of gluing eucalyptus wood waste from sawmills capable of ensure the safe storage and stowage of steel plates and metal profiles. For this, we made a characterization of the physical properties of the wood, determining the apparent density, the moisture content and the shrinkability. The mechanical tests were performed aiming to evaluate the resistance to normal compression to the fibers, the resistance to parallel compression, the shear strength in wood and in the glue line in two conditions of humidity (dry and saturated), besides the delamination test. Non- destructive tests of free transverse vibration, longitudinal vibration and stress wave in the dunnage were performed. Eucalyptus urophylla x grandis wood has good physical properties, which allows its use for making Glulam elements. Results showed a high resistance of the adhesives in the dry condition, not being found the same performance when tested in the saturated condition. Dunnage made of waste presented satisfactory results when compared to the Glulam dunnage made with an entire lamina, being a good substitute for the existing ones.
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    Efeito da termorretificação nas propriedades tecnológicas do bambu
    (Universidade Federal do Espírito Santo, 2013-02-26) Brito, Flávia Maria Silva; Arantes, Marina Donária Chaves; Oliveira, José Tarcísio da Silva; Paes, Juarez Benigno; Vidaurre, Graziela Baptista; Fantuzzi Neto, Humberto
    This work aimed to evaluate the physical and anatomical characteristics of bamboo "in natura", analysing the effects of thermal treatment on the technological properties of glued laminated bamboo thermo-modified (GLBT) and in your natural durability. A total of four culms were collected in age adulthood and cut every to 2.0 m and divided into four lengthwise sections that were immersed in water for 10 days and air-dried. The sections were transformed into flights with dimensions of 0.5 x 3,5 x 45 cm (thickness x width x length) and thermal treated to 100, 140, 160, 180 and 200 °C for one hour for each temperature. T he adhesives used were “Cascophen RS-216-M”, based resorcinol – formaldehyde, “Cascamite PL-2030”,based on urea - formaldehyde, both thermoset and thermoplastic based on one polyvinylacetate, “Cascorez 2500”. The flights thermal treated were scaled according to each proposed test. It was observed that the bamboo culms have a frequency of 0 to 4 vessels.mm-2, whith mean of vessels.mm-2, with long and narrow fibres with length average of 2.72 mm. The basic specific gravity was of 0.66 g.cm-3 and volumetric shrinkage of 15.41%. The total extractives and lignin contents increased as the temperature increase, and holocellulose content has been reduced. Since the temperature of 160 °C was a gain in durability natural bamboo and the dimensional stability of GLBT adhered to RF, but there was a decrease in the values of specific gravity and mechanical properties of the material.