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The characteristics of the behavior of building materials against the fire could realize a preponderant role in the result of an eventual burning situation, difficulting or contributing to reach a critical stage. The present study evaluated the mechanical properties in compression parallel to grain of five pieces of wood from the roof structure of a residence undergo the fire in the rural area of Itapeva/SP. The roof structure was built 25 years ago using wooden beams of the species Guarucaia (Peltophorum vogelianum), where the specimens were obtained. The objective of this work was to realize a case study about strength and stiffness in parallel compression to wood grain in a roof structure of a house located in Itapeva/SP, according to its level of thermal degradation, upon the occurrence of a real fire. In general, despite the many variables involved, the results based on woods of a real fire shown are consistent with the fire simulations provided by the literature.

This research aimed to evaluate the influence of storage time (0, 96 hours) of Pinus elliottii pieces 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.

This research aimed to develop and evaluation the mechanical properties of a particleboard produced with bamboo particles and coconut fiber in three different experimental conditions. The panels were manufactured with castor oil based polyurethane bi-component resin in three different ratios of the adhesive components (pre-polymer and polyol). Mechanical characterization was conducted to determine modulus of elasticity (MOE) and modulus of rupture (MOR) in static bending. For the static bending test the better values were to the experimental condition 2, which relate de proportion of 1:1.5 of pre-polymer and polyol, respectively. This best solution is to reduce the amount of pre-polymer in the formulation of the adhesive, due to decreased of use of chemicals most polluting.

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 use of bamboo in the production of particleboard has been gaining ground as well as other agroindustrial waste, both present a promising alternative for the development of more sustainable materials. This research aims to evaluate the physical properties of particleboard, composed of bamboo particles species Dendrocalamus giganteus and coffee husks particles in the core layer, joined by a castor oil based polyurethane resin. Physical characterization was performed based on the Brazilian Standard [1]. The physical properties of density, moisture content, water absorption during 24 hours and thickness swelling during 24 hours were evaluated. The results were compared with the Brazilian standard [1] and it was concluded that from the evaluated properties, this panel can be used commercially.

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.

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.

Abstract. 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 Em can be employed. Specimens of Pinus elliottii var. elliottii and Pinus elliottii var. elliottii × Pinus cariabeae hondurensis (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.

Alternative raw materials have been studied for the total or partial replacement of wood in wood panels, in order to decrease the use of wood and to recovery waste. The present study tested the influence on the physico-mechanical properties of the panels produced with particles of Eucalyptus saligna and macadamia nutshell. For this were produced panels in proportions of 0%, 30%, 60% and 100% with respect to the macadamia nutshells. With the obtained results it was noticed that the increasing of the nutshell proportion led to a decrease in the dimensional stability, internal bonding and bending strength. These results were primarily due to the geometry of the particles of macadamia nutshell, besides being thicker, not allowing a good interaction between them and the adhesive, they were shorter, reducing the bending strength.

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.