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Corporate representativeness is an important issue for engineering and its industrial sectors, considering that producer associations can defend represent the rights and ambitions of their members. This study aims to investigate timber housing producer participation in generalist organizations, as well as to identify which examples of class entities could be created to consolidate this industry in the Brazilian scenario. A short survey was personally applied to entrepreneurs from the timber house production sector in Brazil. This survey was based in four qualitative queries, whose responses were converted into percentage. The studied producers revealed that the sector does not have an official organization to represent them, forcing them to search for different representation mechanisms from other sectors related to this industry. The lack of corporate and/or labor representation is visible to the point where several interviewed entrepreneurs declared the need to create unions for workers, as well as class associations for producers. Thus, suggestions for a new organization were described to establish a direction for organizing this sector in Brazil. RESUMEN La representatividad corporativa es un tema importante para la Ingeniería y sus sectores industriales, teniendo en cuenta que la asociación de productores puede defender los derechos y ambiciones de sus miembros. Este estudio tiene como objetivo investigar la participación de los productores de viviendas de madera en organizaciones generalistas, así como identificar qué ejemplos de entidades de clase podrían ser creadas para consolidar esta industria en el escenario brasileño. Se aplicó personalmente una breve encuesta a los empresarios del sector de producción de casas de madera en Brasil. Esta encuesta se basó en dos consultas cualitativas, cuyas respuestas se convirtieron en porcentajes. Los productores estudiados revelaron que el sector no tiene una organización oficial que los represente, lo que tiene obligado en buscar diferentes mecanismos de representación de otros sectores relacionados con esta industria. La falta de representación corporativa y/o laboral es visible al punto en que muchos empresarios entrevistados declararon la necesidad de crear sindicatos para los trabajadores y asociaciones de clase para los productores. Así, se describieron sugerencias de nuevas organizaciones para establecer una dirección en la organización de este sector en Brasil.

This research aimed to produce and determine physical and mechanical properties of three-layered particleboard produced with Pinussp. wood particlesand three different times of press, i.e., 3, 5 and 7 minutes. Recommendations of the Brazilian standard ABNT NBR 14810 [1] were adopted to fundament physical and mechanical tests. The properties evaluated were the modulus of rupture (MOR) and modulus of elasticity (MOE) in static bending; internal bond; thickness swelling; water absorption; moisture content and apparent density.The mean values showed, for the physical properties, that all the panels manufactured achievedthe requirements of theBrazilian standard, and for mechanical properties, only the panelsmanufacturedwith 7minutesofpressing timemet therequirements. From the Tukey test results, timesof the pressingcycleinfluencedsignificantlyin allinvestigatedphysical and mechanicalproperties, showed better results the panels madewithseven minutesof the pressingcycle, implyingthat the time ofseven minutesof the pressingcycle is thebest among theinvestigatedperiodsin the manufactureofparticleboard.

The objective of the present work was to study the use of bamboo foils as structural reinforcement for MDP wooden panels. Four wooden panels of homogeneous layer were produced using particles of GT1 and RRIM 600 clones ofHevea brasiliensis(rubber tree), and glued with urea-formaldehyde resin (UF). These panels were also overlaid with foils ofPhyllostachys edulis(mossô bamboo). The tests were realized to evaluate the physical-mechanical characterization according to European standards (EN). The production of the particleboards with reinforcement of bamboo improves the physical-mechanical characteristics of these commercial wooden panels.

These research objectives the development and evaluation of physical and mechanical properties of a hybrid composite manufactured epoxy resin reinforced by Eucalipto sp. wood sawdust and treated piassava fibers. The evaluated properties were modulus of elasticity (MOE) and modulus of rupture (MOR) in static bending, water absorption after 24 hours, porosity and apparent density. Three factors with two levels was evaluated: thickness (3 mm and 4 mm), volumetric resin fraction (45% and 50%) and the use or not of laminate piassava fibers reinforcement, leading to a factorial design of 23 type. Were manufactured four panels, two with 50% and two with 55% of resin, using casting method. For the physical and mechanical properties obtained, the better conditions were the one that uses 50% of epoxy resin, 55% sawdust mass fraction and with the use of laminated piassava fibers reinforcement. The thickness was not statistically significant in obtaining the properties evaluated.

This research aimed to evaluate the influence of storage time (0, 96 hours) ofPinus elliottiipieces and the tests to obtaining modulus of elasticity (static bending and transversal vibration) in glued laminated timber beams, produced with resorcinol based adhesive and 0.8 MPa compaction pressure. After pieces were properly prepared, part of them was used in immediate three manufacturing glulam beams, tested after adhesive cure, and part stored for 96 hours under a roof with a temperature of 25°C and relative humidity of 60% for subsequent manufacturing and testing three other glulam beams. Results of analysis of variance (ANOVA) revealed that the storage period was significant influence in modulus of elasticity obtained in static bending test (8% reduction from 0 to 96 hours). This not occurred with modulus of elasticity obtained by transversal vibration test (no significant influence). ANOVA results showed equivalence of means in both test procedures.

The study aimed to analyze the longitudinal modulus of elasticity (Em), based on static bending tests, in different spans and confirm that it’s necessary adopt as 21 the ratio between span and height of the cross section of the specimen to turn no significant the influence of shear stress on vertical deflection. So, simplified equation to determine Emcan be employed. Specimens ofPinus elliottiivar.elliottiiandPinus elliottiivar. elliottii×Pinus cariabeaehondurensis(hybrid), came from Itapeva region, São Paulo State, Brazil, were considered. Bending tests were conducted in Labs of Experimental Campus Itapeva, UNESP, adapting recommendations of Brazilian Code ABNT NBR 7190. Twelve specimens of each species were tested. The trend lines for the plotted graphics showed clearly a nonlinear behavior until the neighborhood of ratio 21 and no expressive variations after this point, confirming that normative recommendations are correct.

The aim of this research was to produce three-layer Medium Density Particleboard (MDP), with the addition of impregnated paper, in the inner layer, in proportions of 1; 5 and 20%. In this study, MDP was composed with particles of small size in outer layers, and larger particles in internal layer. After panel manufacturing, physical and mechanical tests based on Brazilian Code ABNT NBR 14.810 were carried out to determine moisture content; density; thickness swelling; water absorption; modulus of rupture (MOR) and modulus of elasticity (MOE) in static bending and internal adhesion. Test results were compared to commercial panels, produced with 100% Eucalyptus, considering the requirements specified by Brazilian Code. Properties presented values close to normative specifications, indicating positively the possibility of production of MDP using addition of waste paper impregnated.

The objective of this article was to study the influence of the Pinus taeda wood moisture content to the production of EGP (Edge Glued Panel) in the bonding stage, using PVA adhesive. It was analyzed the joint resistances through shear-stress tests and rupture in the bondline. The wood moisture classes adopted to the panels were: “A” ( [8%, 9%[ ), “B” ( [9%, 10%[ ), “C” ( [10%, 11%[ ), “D” ( [11%, 12%[ ) e “E” ( [12%, 13%[ ). After the panel production, it was sawn the specimens for the resistance shear in the bondline tests by traction. The tests results show that it was statistically significant differences to the values of rupture tensions between A class and B, C, D and E classes. The wood medium rupture presented a tendency to reduce with the moisture increase, and the total rupture in the bondline presented a small tendency of a less number of occurrences with the rupture tension increases.

The waste generated by industries has been an environmental problem to be solved, even in timber chain, whereas the wood has a high potential of reuse. This paper aimed to collect and disseminate the data obtained on lignocellulosic waste generation produced by manufacturers of wood houses located at Brazilian state of Paraná. This information could help the companies with new discussions on the reuse of this waste. A simple survey composed by three questions was applied in the companies in order to verify the current situation of the theme. After the examination, it was checked that many industries do not have the habit to reuse their residual raw materials, and also all these companies do not have any type of periodic evaluation about waste generation, nor they have any kind of waste separation and quantification.

Bamboo is a renewable material that has been gaining attention in several sectors of production and research because of its potential. Its special characteristics of rapid growth, short harvest cycle, diversity and excellent mechanical properties. The objective of this work was a physical-mechanical analysis of flooring manufactured by a combination of bamboo (Dendrocalamus giganteus) laminate slats and wood (Pinus taeda) edge-glued panels (EGP). It was based on the ASTM D2394-83/1994 standard, which describes the procedures for mechanical simulation of in-service floors, such as indentation loads applied on small areas, falling ball impact, rolling load, abrasion and friction tests. The results were satisfactory when compared with those of other types of wood. The research showed lignocellulosic composite of Pine EGP with a bamboo surface, in terms of mechanical strength according the ASTM’s standard, is viable and feasible. Therefore, it results that “EGP/Bamboo” composite can be successfully applied for internal floors.

This study aimed to produce and determine physical and mechanical properties of three layers particleboards produced with Eucalyptus sp. particles, in outer layers, and Eucalyptus urograndis e Eucalyptus saligna bark, in internal layer. Recommendations of the Brazilian Code ABNT NBR 14810-3:2006 were adopted to fundament physical and mechanical tests. Properties considered were modulus of rupture (MOR) and modulus of elasticity (MOE) in static bending; internal adhesion; thickness swelling; water absorption; moisture content and density of the panels. Four different panel compositions were studied, with 5, 10, 15 and 20% of bark (related to particle mass) the internal layer. Results were compared with the requirements of: Brazilian Code ABNT NBR 14810-2; European Code EN 312 and related literature. The produced panels were adequate to all the values stipulated the cited codes and also superior to similar studies found in the literature, for all compositions of bark in internal layer, except for the moisture content test, in which only the composition of 5 % hull met the normative specifications.