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ABSTRACT. This work aimed at the construction and structural evaluation of modular panel with reforested wood, particleboards of sugarcane bagasse and a bi-component resin based on castor oil, for use in lateral closing for construction of crowding pens and chutes for cattle handling facilities. The quality of the particleboards was evaluated considering the requirements of NBR 14810 (ABNT, 2006) and A208.1 (ANSI, 1999). The structural performance of the modular panel was evaluated by the soft body impact testing. The results indicate that the particleboards have physical and mechanical properties that meet the minimum recommendations of the normative documents for structural use. The modular panel shows structural performance suitable to withstand impact loads equivalent to conditions of use, and can be used in cattle handling facilities.

ABSTRACT. This paper examined the potential of manufacturing bonded particleboards using timber industry waste of Pinus spp. Panels were evaluated with 0.6 and 0.8 g cm -3 of density and produced with urea-formaldehyde resin and bi-component polyurethane resin based on castor oil. Panels were made of particles with nominal dimensions 40 x 40 cm and a thickness of 1 cm. As process parameters was adopted 2 -5% moisture content, temperature ranging from 90 to 130°C, average pressure of 5.0 MPa and resin content from 10 to 15% of the weight particles. This study determined physical-mechanical properties of the panels, following the recommendations of ABNT (2006) NBR 14810. The results indicated statistically significant difference (p < 0.05) in physical and mechanical properties of the panels studied. Panels were classified by ANSI (1993) A208.1 -Mat-formed wood particleboard: Specification, as of low and medium density. Scanning electron microscopy images (SEM) illustrated the agglomeration of particles for the different resins. The polyurethane resin based on castor oil stood out as a viable alternative in the production of particleboards with timber waste.

In order to contribute to the dissemination of lignocellulosic residues in the composite materials manufacturing, this study aimed to investigate the influence of a soaking in the presence of natural bacteria and fungi on the resistance to axial traction of açaí fibers (Euterpe oleracea Mart.). The stipulated factors and levels were the source of water, i.e., Rio Guamá, Pará Sanitation Company COSANPA and Cassava, as a catalyst and the mass concentration of water on the açaí cores, i.e., 2%, 4%, 6%. In this way, 9 different experimental conditions were performed, together with the reference condition, i.e., açaí fibers without the soaking. In all, 200 specimens were cast, with 10 of each composition. The analysis of variance results revealed that the individual factors were not significant in obtaining the axial tensile strength, providing equivalent results regardless of the concentration and type of water. However, the interaction between the factors was considered significant, showing that the best treatment for the fibers came from the use of 2% cassava scraps. The axial tensile strength was 47% greater than the axial tensile strength obtained from the reference sample. Furthermore, 59% surpassed the reference sample, showing the efficiency of the soaking in the presence of natural bacteria and fungi treatment.