Análise do efeito de grupo em ligações com parafusos passantes na madeira da espécie Apuleia leiocarpa

Abstract

Wooden buildings are designed and built with the union of several structural elements such as beams, collun, etc. The structural elements as well as the connections that unite them must be designed in order to meet certain requirements such as economy and safety. The wooden connections, in particular those formed by metallic pins, present a characteristic phenomenon called group effect, which consists in the reduction of structural efficiency depending on the number of pins in line. This phenomenon has been studied for years and is already foreseen in normative documents, however, with significant differences. Considering that the brazilian norm for the design of wooden structures is currently under review, the opportunity arises to experimentally verify the group effect and compare the results with the recommendations of the normative documents. In this work, connections with M10-ISO8.8 hexagonal bolts were evaluated, in wood of the Apuleia leiocarpa species (garapeira), with 5d spacing, varying the number of screws in line. The results indicated that the european normative document is in favor to safety and the brazilian and north american normative documents are opposed to safety.