Fundamentals for the fabrication of a displacement meter to determine the elastic constants of wood, considering its anisotropy

• Autor(a) principal: Carrasco, Edgar Valdimiro Mantilla
• Data de Publicação: 2022
• Outros Autores: Alves, Rejane Costa, Smits, Mônica Azevedo, Pizzol, Vinnicius Dordenoni, Oliveira, Ana Lúcia Crespo, Mantilla, Judy Norka Rodo
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Research, Society and Development
• Texto Completo: https://rsdjournal.org/index.php/rsd/article/view/31910
• topic: Portable displacement meter; Tropical wood; Elastic constants; Flexibility matrix.; Medidor de desplazamiento portátil; Madera tropical; Constantes elásticas; Matriz de flexibilidad.; Medidor de deslocamento portátil; Madeira tropical; Constantes elásticas; Matriz de flexibilidade.

The objective of this work is the development of a portable displacement meter to determine the elastic constants of Brazilian woods. The elastic constants that give rise to the flexibility matrix were determined through the compression test on specimens made with the orientation of the fibers in six directions: radial, tangential, longitudinal, longitudinal-radial, longitudinal-tangential and radial-tangential. The species used were: Dinizia excels (angelim vermelho), Apuleia leiocarpa (garapa) e Peltogyne discolor (roxinho). In order to reduce cost and time spent on gluing electrical strain gauges, a displacement meter was developed, with sufficient accuracy to determine the deformations in all directions of the fibers and that allows the reuse of the displacement meter in other tests of compression. An arc-shaped steel strip was used, on which four electrical strain gauges were glued, two at the top and two at the bottom. To obtain greater sensitivity in bending and to eliminate the influence of temperature on the deformation of the electrical strain gauges, they were configured in a Wheatstone full bridge circuit, and then connected to a data acquisition system. The results allowed to conclude that the displacement meters were efficient and effective to determine the deformations during the compression test and consequently to determine all the components of the flexibility matrix.