Utilização de viga vagão formada por peças retangulares de madeira para sustentação de fôrmas para concreto

Abstract

The system called king or queen post truss, also inverted truss beam, formed by a main beam with rectangular cross section and one or two struts tied to rods attached to the ends of the piece through the bottom of the rods, is an interesting option for use in support of formwork for concrete. System results in a lightweight, easy handling, good stiffness and good mechanical strength. This study evaluated the system numerically and experimentally. The positions of the fixation struts and rods, as well as the relationship between span and length of the struts, were the parameters considered to understand the system\'s efficiency. The numerical analysis was made by the software ANSYS® using the finite element method. The efficiency of the system was evaluated by comparison between the simple beam and the inverted trus beam. The beams mounted with Angelim Vermelho have a gain in stiffnes of 147 %, when wire rope is used as cable. This efficiency increases to 623 % when the cabe is steel rod. Beams of Pinus had a gain of 518 % for system with steel rod.