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Made available in DSpace on 2021-07-14T10:30:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-12-05. Added 1 bitstream(s) on 2021-07-14T11:31:46Z : No. of bitstreams: 1 S1678-86212020000100277.pdf: 996165 bytes, checksum: 9855a82ce1fbbc91dac748074b6cd567 (MD5) As gridshells são estruturas leves, que permitem a obtenção de grandes vãos livres, além de uma ampla variedade de formas arquitetônicas. No entanto, no Brasil, não existem registros da construção desse tipo de estrutura (em caráter permanente) nem muitas informações bibliográficas sobre o seu comportamento estrutural. Neste manuscrito, são apresentados os principais aspectos teóricos, como também os detalhes de projeto e de construção de uma gridshell, construída em madeira, em escala real. Os custos de construção também foram relacionados neste caso. Na confecção da estrutura utilizou-se uma configuração de malha quadrangular plana, formada por ripas duplas de madeira de Lyptus (Classe D40), unidas ortogonalmente entre si por parafusos com diâmetro de 6,35 mm. A malha plana (com dimensões totais de 9 m x 9 m) foi deformada até a obtenção da forma curva desejada e, posteriormente, travada por contraventamentos diagonais. A bagagem de conhecimento adquirida como resultado dessa aplicação prática levou a um aperfeiçoamento significativo da ideia de projeto inicial, relacionada ao controle da forma da estrutura durante as fases de montagem e à otimização das estratégias executivas. As recomendações de construção aqui apresentadas enriquecerão a literatura nacional sobre o assunto tendo-se em vista a carência de textos dessa natureza. Gridshells are light structures that allow the obtention of large spans, as well as the use of a wide variety of architectural shapes. However, in Brazil, there are no records of the construction of this type of structure, neither literature available on this type of structural composition. This paper presents the main theoretical aspects, as well as design and construction details of a gridshell built in wood in real scale. The construction costs are also reported. The structure was built by using a quadrangular flat mesh configuration, formed by double slatted Lyptus wood (Class D40), joined orthogonally, using 6.35 mm diameter screws. The plane mesh (with total dimensions of 9 m x 9 m) was bent until the desired curve was achieved. The system was subsequently locked by diagonal bracing elements. The knowledge obtained through this practical application led to a significant improvement in the original design idea related to controlling the shape of the structure during the building phase and the the optimisation of the executing strategies. The building recommendations presented in this paper will be a contribution to the scarce literature on the subject currently available in Brazil. Universidade Estadual Paulista Rewood - Soluções Estruturais em Madeira Laminada Colada Universidade Estadual Paulista

Glued laminated timber is a structural engineered product that requires precision and strict quality control in its manufacture. For ensure that produced elements properties are in compliance with regulatory requirements, final product must be tested under laboratory conditions. Determining factors in final glulam pieces cost are the type and the quantity of adhesive used in structural elements manufacture. This study aimed to investigate, aided by three point static bending tests and variance analysis (ANOVA), influence of glue lines (3, 5, 7) and lamellae (4, 6, 8) on strength (MOR) and stiffness (MOE) properties of glulam beams manufactured with Pinus oocarpa (CCA treated) and bonded with Phenol Resorcinol resin (Cascophen RS-216-M). These beams presented nominal dimensions 90mm wide; 100mm height; and 1350mm length. For 100 mm fixed height, three beams configurations were tested (a) with four lamellae of 25 mm (3 glue lines); with 6 lamellae of 16,7 mm (5 glue lines) and 8 lamellae of 12.5 mm each (7glue lines), being fabricated 6 beams for experimental condition. In addition to investigating influence of glue lines and lamellae number, possibility of estimating MOE and MOR based on apparent density was also evaluated. ANOVA results showed no significance about glue lines number (or lamellae thickness) in strength and stiffness values, implying, for economic reasons, be configuration with four 25mm lamellae the best among tested beams. From regressions, apparent density was only significant in MOE estimating (R 2 = 46.90%), indicating not be possible to estimate the stiffness and strength values of the glued laminated timber evaluated by the apparent density.

Glued laminated timber (glulam) is an engineered product that requires manufacturing precision in all its stages. The finished product can only be tested in laboratory conditions; however, it is necessary to provide the quality control in production to ensure that glulam properties are appropriate to the product specified requirements in accordance with proper codes. This research aimed to evaluate the proposed trials conducted with combinations of Parica (Schizolobium amazonicum, a tropical wood species coming from a certificate reforestation area), three adhesives (polyurethane, phenol resorcinol formaldehyde, melamine formaldehyde) and two types of treatment (CCA, CCB). The shear strength and delamination test results of all the treated samples showed the good performance of Parica glulam, which can be used to indoor and outdoor applications.

http://dx.doi.org/10.5902/1980509816612A Madeira Laminada Colada (MLC) apresenta uma grande gama de aplicações. No Brasil, o seu emprego na forma de cruzetas para postes de rede aérea de distribuição de energia elétrica tem despertado a atenção de companhias do ramo, motivadas pelo potencial de emprego deste material. Dentre os fatores que influenciam o desempenho mecânico de soluções em MLC destacam-se a eficiência e a afinidade dos adesivos para com as espécies de madeiras utilizadas, o tipo de tratamento e o teor de umidade das lâminas de madeira, motivando o desenvolvimento de novas pesquisas nesta temática. Este trabalho objetivou investigar, via Método de Planejamento Fatorial de Experimentos (DOE), a influência dos fatores tipo de madeira (pinus; teca; eucalipto), adesivo (Purbond; Cascophen) e tratamento (CCA; CCB; CCBS) nas variáveis respostas resistência ao cisalhamento e à delaminação, consistindo nos mesmos fatores e combinação avaliados no projeto de Pesquisa e Desenvolvimento da ANEEL/EESC-PD220-07: Cabeça de Série da Cruzeta de MLC. Os resultados da análise estatística revelaram que o fator tipo de madeira expressou efeito significativo para ambas as variáveis respostas avaliadas, o mesmo não ocorrendo com os fatores tipo de adesivo e de tratamento. Já o teor de umidade mostrou ser significativo em todas as espécies de madeira quando analisada a resistência ao cisalhamento, apresentando a madeira de teca a maior resistência ao cisalhamento e à delaminação.

Made available in DSpace on 2018-12-11T16:47:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-01-01 In this work was evaluated by numerical simulation, from the use of ANSYS software, version 10.0, the be-havior of steel connections made by self-tapping screws with diameter of and 11 mm, in X position, in specimens made with reforested wood of the type Eucalyptus urograndis. The stiffness k (force versus displacement) of the connection system was evaluated, in this case, by direct shear testing simulation (direct shear), considering ½ structure with applied load until the rupture of the specimen. The strategy of using ½ symmetrical structure of specimen aimed to reduce the time of numeric processing of the specimen. In the modeling of wood and steel connectors was used the finite element solid45. The numerical analysis results were com-pared with results obtained from experimental tests on wood specimens with same configuration and loadings used in experimental analysis. The calibration of the numerical model was made from the comparison of numerical and experimental curves “applied force” versus “obtained displacement”. The numerical results for the strength and stiffness k of the connection system analyzed X showed a good agreement with the experimental results and the values of experimental results were fairly smaller than the numerical values. As a result presents mainly the entire numerical modeling strategy used in this case. Laboratório de Madeiras e Estruturas de Madeiras LaMEM SET/EESC/USP Laboratório de Propriedades Mecânicas dos Materiais UNESP Laboratório de Propriedades Mecânicas dos Materiais UNESP

Wood is a renewable source of structural material with high relative strength/weight, low energy production, which kidnaps and stores carbon in its production. The large use of wood is due to its special qualities as raw material for other products manufactured in residential construction or major works such as bridges, has been widely used in roofing for industrial and commercial buildings. Commercially there are limitations on the length of the wood, resulting from the extraction of tree trunks, thus requiring the adoption of binding elements is the use of self-tapping screws efforts required by side and which can be axial, shear, tensile or compression. Whereas in Brazil does not yet exist and the promising future of the product, this research aims to study the behavior of self-tapping screws together with Brazilian reforestation species ofPinusoocarpaandLyptus(softwood and hardwood). Rothoblaas self-tapping screws had a good penetration in both woods without requiring pre-drilling, the species of Lyptus wood showed the highest values of strength and the inclination of the screws, at 45 degrees showed the best results on either species of wood.

The segment of wood preservation is responsible for considerable waste generation, typically consisting of products not approved by quality control or post-consumer. Another type of waste to be considered is tire rubber, which accumulate due to deficiencies in logistics and fiscalization. Although it has been classified as intractable, tire rubber enables to add properties in products that promote the use of materials in particulate form. This study aimed producing and characterization of particulate composites containing CCB-treated Pinus sp. with addition of tire rubber, and castor oil-based polyurethane resin. Properties of particleboards were obtained according to Brazilian Code NBR 14810:2006. The results were compared by statistical analysis. It was observed that addition of tire rubber waste resulted in higher densities, and rubber proportion of 50% showed greater internal bond. In some cases, strength in bending of panels was in accordance with standards requirements and commercial products destined for acoustic conditioning, enabling different applications.

Parica (Schizolobium amazonicum Herb.), is a native species from Amazon region, with very susceptible wood to xylophagous agents attacks. Therefore, to know the permeability of this species is information to define the chemical treatment suitable for the durability of this wood in use. For this study, it sawed wood from planted areas of the amazon region was used. It is possible to determine the permeability with the aid of proper equipment. The specimens, used in this research, were obtained randomly from pieces, 6 specimens for each one of the fluids tested: atmospheric air, distilled water and CCA chemical preservative. The value of atmospheric air permeability was 504.15 cm³/cm.atm.s with variation coefficient of 7.78%. For distilled water, the permeability and the variation coefficient were 10.84 cm³/cm.atm.s and 23.16%, respectively. Regarding the CCA, the permeability was 228.69 cm³/cm.atm.s and the variation coefficient 61.97%.

MDF in Brazil is an almost recent product, available in the market from the late '80s. The resin content appears as one of the factors that most influence the final properties of MDF panels. Identification of how these factors interact is very useful for improving performance and energy inputs, determining ideal resin content based on the desirable properties. This paper analyzes the most important properties of a MDF panel in the industry, in directions: perpendicular and parallel to the direction of production, thus verifying the homogeneity throughout the panel, according to EN 622-5, by determining the MOE and MOR in bending, draw perpendicular, swelling and water absorption. In the same way, it was analyzed if there is a direct relationship between the bending and tensile perpendicular to face properties. Results showed that the panels studied cannot be considered within the normative standards, despite having attended many of these requirements, for example, in presenting an MOE greater than the relevant standard. Through the analysis of variance, we observed the uniformity of properties in both directions studied. As a result of feedback from the wheel perpendicular and thickness swelling, can admit a bad distribution of the patch panel and a larger amount of paraffin, which was observed by the inconsistency between these properties. Through the low value in the analysis of R², we can say that there isn’t a correlation between the MOR in bending and tensile strength perpendicular.

The Edge-Glued Panel is produced using sawn wood, i.e., lumber, with or without butt joints and edge-glued lumber. It can be composed with one layer, but the most common is with three layers (two external longitudinal and one transversal). This panel is used in Europe for furniture and forms of concrete structures. The resin applied in the gluing is based on urea-formaldehyde and phenol-formaldehyde. Due to the importance of this panel, this research aims to analyze the use of Transversal Vibration techniques for EGP grading. For this purpose, twelve EGP panels of three layers were produced and tested in order to determine the modulus of elasticity and modulus of rupture in static bending and dynamic modulus. The results showed nonexistent correlations among the dynamic modulus of elasticity with EGP density and between the modulus of rupture in static bending with the dynamic modulus, providing just a good correlation between statistic and dynamic modulus of elasticity.

Glued laminated timber is an engineered product that requires precision manufacturing in all its stages. The finished product can only be tested in laboratory conditions. However, it is necessary to have quality control in the production to ensure that the properties of the glulam are appropriate to the product specified requirements in accordance with the standards. In Brazil is still no specific standard of qualification for the manufactures of Glulam. In this context, different kinds of wood, adhesives and preservative treatments in the composition of Glulam can be used. This paper aims to evaluate the proposed trials conducted with combinations of four Brazilian reforestation species, three adhesives and three types of preservative treatment. As a result was observed that combinations, which showed the best performance, were pine and parica wood, with any type of adhesive or treatment investigated, which can be used in exterior applications. Lyptus ® wood for any combination of treatments falls into the internal use class. Teak wood can be used indoors (adhesive polyurethane and all kinds of treatment) or external (phenol resorcinol formaldehyde adhesive and all kinds of treatment).

Made available in DSpace on 2018-11-12T17:27:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-01-01. Added 1 bitstream(s) on 2021-07-14T17:51:20Z : No. of bitstreams: 1 S1678-86212016000100221.pdf: 349423 bytes, checksum: 82fc08265ff05fc3ef7688af1d56a8bc (MD5) Resumo A utilização de elementos estruturais de madeira laminada (ou lamelada) colada (MLC) requer um estudo experimental das combinações entre a espécie de madeira e o adesivo utilizado. Este trabalho objetivou o estudo da combinação espécie-adesivo na resistência a tração e na falha da linha de cola de corpos de prova de madeira de maçaranduba (Manilkara huberi) confeccionados com e sem emendas dentadas finger joint. As colagens foram realizadas com lâminas sem tratamento preservativo, com aproximadamente 12% de umidade e com o emprego do adesivo mono-componente do tipo poliuretano Purbond HB 712. A gramatura de adesivo utilizada nas emendas dentadas foi linha simples de cola com aproximadamente 200 g m-2 e pressão de contato igual a 10 MPa. Após sete dias de cura do adesivo foram realizados testes de tração nos corpos de prova com e sem emendas dentadas, possibilitando julgar, também por meio da análise de variância, a eficiência das emendas testadas. Os resultados da experimentação revelaram a ineficiência da interface entre o adesivo e a madeira de analisada, pois a ruptura ocorreu na linha de cola, categorizando modo de ruptura do tipo 1, que corresponde à pior situação de falha. Abstract The use of glued laminated timber structural elements requires an experimental study of combinations of wood species and the adhesives used. This aim of this study was to investigate the wood species-adhesive combination in the tensile strength and failure modes of Manilkara huberi wood species manufactured with and without finger joints. The assemblies were made with untreated layers of wood with approximately 12% moisture using the polyurethane-based mono-component adhesive model Purbond HB 712. The amount of adhesive used in the finger joint was a single line of glue with 200g m-2 and pressure of 10 MPa. After 07 days of curing the adhesive, tensile tests were performed on specimens with and without finger joints, allowing the assessment of the efficiency of the joints also through variance analysis. The results of the tests revealed the ineffectiveness of the interface between the adhesive and the Manilkara huberi wood, since the rupture occurred on the glue line, configuring a type 1 failure mode, representing the worst rupture situation. Universidade Estadual Paulista Universidade de São Paulo Universidade Federal de São Carlos Universidade Estadual Paulista

The dimensions of test specimens employed in wood characterization are always established searching situations where friction interference is annulled in deformation measurements. NBR 7190 norm (ABNT, 1997) - Annex B adopts specimens to compression parallel to grain tests with 1:3 ratio between the side (50 mm) of cross section and length, while COPANT 464 (COPANT, 1972) and ASTM D 143 (ASTM, 1982) establish 1:4 ratio. The purpose of this research was to determine whether 1:3, 1:4 and 1:5 ratios in the specimens, referring respectively to 150, 200 and 250 mm lengths could influence the E c0 obtained in compression parallel to grain test. Analyses were performed in ‘Canelao’ (Nectandra membranacea), Corymbia citriodora and ‘Angelim’ (Vatairea sp.) species. E c0 values for the mentioned species were statistically equivalent at 5% significance level, demonstrating that length variation did not affect the property values analyzed.

A Madeira Laminada Colada (MLC) é um produto engenheirado que requer precisão de fabricação em todos os seus estágios. O produto acabado pode somente ser testado em condições laboratoriais, entretanto é necessário o controle de qualidade na sua produção para assegurar que suas propriedades sejam conformes aos requisitos especificados para o produto de acordo com as normas vigentes. Considerando que no Brasil ainda não existe uma norma específica de qualificação para a MLC e o potencial que esse material tem de ocupar espaço no mercado futuro, este trabalho tem por finalidade propor recomendações metodológicas para os ensaios de controle de qualidade de elementos estruturais de MLC, tendo como pontos de partida as Normas Canadenses CSA 0177-2006, Estadunidenses AITC A190.1-2007, Européia EM 386-2001 e Chilena NCh2148.cR2010, com ênfase principal no sistema de controle de qualidade dos materiais empregados na produção de MLC. Para a avaliação do método proposto foram realizados ensaios com três combinações de espécie-adesivo-tratamento, os mesmos utilizados no projeto de Pesquisa e Desenvolvimento da ANEEL/EESC: \"PD220-07 - CABEÇA DE SÉRIE DA CRUZETA VERDE DE MLC\". Os resultados mostram que o método proposto é adequado e de suma importância no estudo de MLC estrutural em função da sensibilidade de combinação espécie-adesivo-tratamento. The Glued Laminated Wood is an engineered product that requires precision manufacturing in all its stages. The finished product can only be tested in laboratory conditions, however it is necessary to quality control in their production to ensure that the properties of the MLC are appropriate to the requirements specified for the product in accordance with the standards. Considering that in Brazil there is still no specific standard of qualification for the manufacturers of Glulam and the promising future market, this paper aims to propose some methodological recommendations for quality control testing of structural elements of Glulam-based Canadian Standards CSA 0177 - 2006, AITC A190.1-2007 American, European and Chilean NCh2148.cR2010 AT 386-2001, with primary emphasis on the control system of quality of materials used in the production of Glulam. For the evaluation of the proposed trials were conducted with combinations of three species - adhesive - treatment that were used in the design of Research and Development ANEEL/EESC \"PD220-07 - HEAD OF SERIES CROSSHEAD MLC\". The results show that the proposed method is suitable and of paramount importance in the study of structural MLC according to the sensitivity of species combination - adhesive - treatment.

A madeira é um material estrutural de fonte renovável, com alta relação resistência/peso, baixo consumo energético de produção, sequestra e armazena carbono em sua produção. A aplicação da madeira como material de construção civil é fundamental, pois além de ter qualidades muito especiais como matéria prima para outros produtos industrializados na construção de residências ou em obras de grande porte como pontes e passarelas, vem sendo utilizada amplamente em coberturas para edifícios industriais/comerciais. Comercialmente, existem limitações do comprimento das peças de madeira, fruto de sua extração de troncos de árvores, requerendo assim a adoção de elementos de ligação das peças estruturais. Uma das mais recentes alternativas para as ligações com elementos estruturais de madeira é a utilização de parafusos auto-atarraxantes solicitados por esforços que podem ser laterais e axiais, de cisalhamento, tração ou compressão. Considerando que no Brasil ainda não existe, e com o mercado futuro promissor, este trabalho tem por finalidade realizar um estudo teórico, numérico e experimental das ligações com parafusos auto-atarraxantes com diâmetros de 9 mm e 11 mm e espécies de reflorestamento de Pinus Oocarpa e Lyptus®, com a finalidade de propor os critérios de dimensionamento para estas ligações. Os resultados obtidos mostram que os ângulos de 45º entre a força aplicada e a posição de penetração do parafuso conduz aos melhores valores de resistência e rigidez das ligações. Alem disto, com base na experimentação realizada, conclui-se que o critério proposto pelo EuroCode5 se mostra adequado para o dimensionamento das citadas ligações. Wood is a renewable source of structural material with high relative strength/weight, low energy production, kidnaps and stores carbon in its production. The use of wood as a construction material is critical because besides having very special qualities as raw material for other industrialized in building homes or large works such as bridges and walkways, product has been widely used in roofing for industrial buildings and commercial buildings. Commercially there are limitations on the length of the wood, resulting from the extraction of trees, thus requiring the adoption of binding elements of the structural parts. One of the newest alternatives for connections with wooden structural elements is to use self-tapping screws requested by efforts that may be lateral and axial, shear, tensile or compressive. Whereas in Brazil does not yet exist and the promising future market, this study aims to make a theoretical, numerical and experimental study of connections with self tapping screws with diameters of 9 mm and 11 mm and two species of reforestation Pinus oocarpa and Lyptus®, in order to offer a criteria for these connections. The results obtained show that the 45° angle between the applied force and the position of the screw penetration leads to a better strength values and stiffness. Besides this, based on experiments conducted, it has concluded that the criteria proposed by Eurocode5 prove suitable for this type of connection.

This research aims to study the shear strength of species-adhesive-moisture-waterproofing combinations and delamination of Glued Laminated Timber (Glulam) made with Parica (Schizolobium amazonicum Herb) and Lyptus Wood species, using two different adhesives, the bicomponent resorcinol-formaldehyde based adhesive (CASCOPHEN RS-216-M) with catalyst FM-60-M and the bicomponent melamine-urea based adhesive with catalyst AkzoNobel MUF 1242/2542, both in a proportion of 100 parts/adhesive mass and 20 parts/catalyst mass and waterproofed by the commercial product ProtectGuard. Shear strength tests in adhesion line were performed according to North American Standard AITC 190: 2007 and delamination tests were carried out obeying Canadian Code CSA 0177: 2006. The results show that average values of great shear strength were obtained in tests on the glue line of the specimens treated with the waterproofer, however, within them, the timber was dry. Lyptus Glulam beams did not present a performance in delamination that was compatible to external applications, but Parica beams are fit to this use, once they are previously treated.

O controle da qualidade é fundamental no processo de fabricação de peças de madeira laminada colada (MLC), e uma das formas desse controle pode ser por meio da avaliação não destrutiva do módulo de elasticidade. O objetivo deste trabalho foi comparar os valores de módulo de elasticidade das peças de MLC obtidos por meio do ensaio de vibração transversal livre e do ensaio de flexão estática, ambos feitos antes e após tratamento preservativo (contra a ação de agentes biológicos), realizado pelo processo de Célula Cheia. No total, foram produzidas 54 peças de MLC de dimensões nominais de 9 cm x 9 cm x 200 cm, com três espécies de madeira de reflorestamento coladas com dois adesivos de aplicação estrutural e tratadas com três preservantes. Foi obtida uma correlação significativa entre os valores do módulo de elasticidade obtidos pelos dois métodos (r variou entre 0,85 e 0,99). Concluiu-se que o ensaio de vibração transversal livre pode ser utilizado para avaliação do módulo de elasticidade de peças de MLC, sendo uma alternativa ao ensaio de flexão estática

Esse trabalho tem como objetivo avaliar a resistencia ao cisalhamento na linha de cola de madeira laminada colada (MLC) fabricadas com tres especies florestais: Tectona grandis, Pinus oocarpa e Eucalyptus sp .. As colagens foram realizadas com lamelas sem qualquer tratamento quimico preservativo, utilizando-se de adesivo bicomponente a base de melamina-ureia-formaldeido (MUF). Foram feitos ensaios de resistencia ao cisalhamento na linha de cola para madeira nas condicoes de umidade de equilibrio local e alta umidade, bem como ensaios de delaminacao. Os resultados obtidos a partir dos ensaios de resistencia ao cisalhamento na linha de cola na condicao seca e dos ensaios de delaminacao apontam para o melhor desempenho da especie Pinus oocarpa. Concluiu-se que ha potencialidade dessa especie para producao de MLC utilizando o adesivo MUF.