Avaliação do comportamento de ligações com parafusos auto-atarraxantes em vigas de MLC

• Ano de defesa: 2004
• Autor(a) principal: Renata de Souza Duarte
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Parafuso auto-atarraxante; Ligação rígida; Madeira laminada colada; Ensaios não-destrutivos; Ligações parafusadas; Engenharia de estruturas; Laminas de madeira; Chapas de metal
• Link de acesso: http://hdl.handle.net/1843/FACO-6AZNQ6

In this work an experimental study of moment splices between glulam beams using lag screws and metallic plates, for transmitting bending moment and shear force, was presented. Glulam beams made of Eucalyptus grandis (Brazilian species) were used for the real advantages of this material when compared to solid sawn lumber. In order todefine new techniques for the glulam manufacturing, non-destructive tests were performed and evaluated to determine the elasticity modulus of the planks. With the average speed of the ultrasonic waves, the density and the moisture content of the plank it was possible to find a consistent equation to determine its modulus of elasticity and compression strength parallel to grain. Found the plank modulus of elasticity it was possible to set up the planks in the glualm beans. The method defined to manufacture glulam beams will make it possible to better the woods quality and usage, and also to decrease the variability in the wood properties. And all this with a small implementation cost. The lag screws and the connection arrangement chosen for the experimental studywere supported by an extensive bibliographic review in order to improve and make possible an evolution in the Brasilan practices. An experimental study on the influence of the number of lag screws in the beam stiffness through flexural tests with different quantities of lag screws in the connection was performed. Based on the experimentalresults, it was possible to define the necessary number of lag screws to recover the flexural beam stiffness. When the number of lag screws is more than necessary, the flexural stiffness is higher than the original beam stiffness. Thus, the connection is working also reinforcing the beam. The rotational stiffness was determined by the experimental results. This allowed defining the connection as rigid or semi-rigidaccording to the number of lag screws. The experimental results ensure the efficiency and the great potential of utilization of both the defined methodology for manufacturing of glulam peaces and the connection arrangement using lag screws.