CONNECTIONS IN PIECES OF WOOD WITH LAG SCREWS

摘要

The objective of this paper is to verify the acting of connections that use a model of lag screw, solicited by efforts of axial withdrawal. It also presents evaluation of connection strength of the screws fastened in the parallel or perpendicular direction in relation to the fibers of the wood, the strength of the connection in function of the number of lag screws, the strength of the connection in function of the spacing between the lag screws and the strength of the connection with the variation of both density and humidity. The wood species used as base for this research were Pinus Taeda (Pinus Taeda L.), Eucalipto Grandis (Eucalyptus Grandis) and Cupiuba (Goupia glabra). This paper offers information for the lag screw design, which is not found in the Brazilian Code "NBR 7190 -Projeto de Estruturas de madeira".