Estudo comparativo dos critérios de dimensionamento de ligações em estruturas de madeira considerando a norma europeia EUROCODE 5 e a norma brasileira NBR 7190

Abstract

As a structural material obtained from a renewable source, the use of wood as a civil construction material is of great importance, mainly due to its physical and mechanical properties. Due to the length limitations of trees related to its extraction, alternatives were created that could overcome these restrictions. Thus, the use of connections between the wooden pieces is fundamental for the construction of structural elements. The types of connections most used in wooden structures are metal pins such as nails and steel bolts. Standards code NBR 7190:1997 and EUROCODE 5:2004, present in their formulations, dimensioning criteria for connections with metallic pins, with significant differences between each standard. It is observed that the main difference is the failure modes for this type of connection. Thus, the objective of this monograph was to carry out a comparative study between the design criteria between NBR 7190:1997 and EUROCODE 5:2004 standards guideline. Using examples for analysis and comparison of results, an electronic spreadsheet for automatic calculation of connections with metallic pins was created. The major differences observed are related to the fact that the Brazilian standard has only two failure modes, while the European standard has a greater number of possible collapse modes for these connections. Other differences were observed, such as in the cases of connections with different wood species, and, unlike the European standard, the Brazilian standard does not address guidelines on this topic in its text. Thus, it is observed the importance of a comparative evaluation in relation to the guidelines for the dimensioning of connections of the different normative codes.