Simplified Methods to Obtain Efforts in The Joint Lines of Metal Connectors of Wood Truss Conference Paper uri icon

abstract

  • This paper presents a simplified method to obtain the distributions efforts in the joint lines in a wood truss node connected by metal plates fasteners, as function on the efforts transferred by each wooden element to the connection node. Although this verification is simple to solve in cases of simple joint geometries and/or symmetrical loading in relation to the node. The problem becomes complex in cases where the connection is composed of more than one joint line, without axis of symmetry and/or cases in which the loads are not symmetrical in relation to the node. This work aims to verify and compare three method to obtain the distribution efforts in the joint lines. Method 1 is based on the static balance between the efforts in anchors and their distribution over the adjacent joint lines. Method 2 (fictitious line) was presented to obtain the distributions efforts in the rupture lines from the distribution of efforts into composite lines (ensuring the balance of efforts on the fictitious line and the transmission of these efforts to the various rupture lines). Method 3 (obtaining the distribution by numerical models, in this case the MEF) allows to obtain the distribution along the line(s) for any configuration and composition of this(s), in addition it also allows to introduce the real stiffness of the plate and consequently a more realistic deformation/stress. The checks are carried out through Eurocode 5 EN 1995-1-1: 2004 [1] and through the CSI (Combined Stress Index), which represents the structural efficiency, in order to conclude the veracity of the method.
  • This paper presents three simplified methods to obtain the distributions efforts in the joint lines in a wood truss node connected by metal plates fasteners, as function on the efforts transferred by each wooden element to the connection node. Although this verification is simple to solve in cases of simple joint geometries and/or symmetrical loading in relation to the node. The problem becomes complex in cases where the connection is composed of more than one joint line, without axis of symmetry and/or cases in which the loads are not symmetrical in relation to the node. This work aims to verify and compare three methods to obtain the distribution efforts in the joint lines. Method 1 is based on the static balance between the efforts in anchors and their distribution over the adjacent joint lines. Method 2 (fictitious line) was presented to obtain the distributions efforts in the rupture lines from the distribution of efforts into composite lines (ensuring the balance of efforts on the fictitious line and the transmission of these efforts to the various rupture lines). Method 3 (obtaining the distribution by numerical models, in this case the MEF) allows to obtain the distribution along the line(s) for any configuration and composition of this(s), in addition it also allows to introduce the real stiffness of the plate and consequently a more realistic deformation/stress. The checks are carried out through Eurocode 5 EN 1995-1-1: 2004 [1] and through the CSI (Combined Stress Index), which represents the structural efficiency, in order to conclude the veracity of the method.

publication date

  • January 2020