Materials and Structures

, 34:100 | Cite as

Pull-out behaviour of steel rods bonded into timber

  • J. G. Broughton
  • A. R. Hutchinson
Scientific Reports

Abstract

Connections for timber structures using concealed bonded-in rods offer one possible solution to the development of more efficient joining methods. However the importance of certain basic joint characteristics, and the influence of adhesive type and properties, are not yet fully understood and as such design criteria are lacking. This paper describes a comprehensive experimental and numerical investigation into the fundamental material and joint geometry characteristics of rods bonded in to timber. The adhesive type and performance are both considered, along with test configuration and joint parameters that included rod embedment length, rod diameter, annular bondline thickness, multiple rods and rod spacing. A novel approach that involved end-profiling of the bond area was also investigated. It was found that epoxy adhesives out-performed all other types investigated, and pull-out strengths can be significantly improved through careful selection and optimisation of the joint geometry.

Keywords

Timber Failure Load Epoxy Adhesive Laminate Veneer Lumber Bond Area 

Résumé

L'assemblage des structures en bois de construction au moyen de tiges en acier enfoncées à l'intérieur du bois offre une solution possible à l'élaboration de méthodes plus efficaces pour relier ces types de structures. Cependant, l'importance de certaines caractéristiques de base des joints et l'influence du type et des propriétés de l'adhésif ne sont pas encore entièrement assimilées: il manque des critères de conception. Cet article décrit une recherche expérimentale et numérique sur les caractéristiques foundamentales des matériaux ainsi que sur la géométrie d'assemblage des tiges en acier fixées au bois de construction. Le type et la performance de l'adhésif ont été considérés, ainsi que le mode d'essai (tiges simple, multiples et espacement des tiges multiples) et les paramètres des joints comprenant: le diamètre, la longueur d'enfoncement et l'épaisseur annulaire d'adhérence de la tige. Une nouvelle approche qui mettait en application une méthode visant à profiler l'aire d'adhérence des tiges a également été étudiée. On a constaté que les adhésifs époxydes ont surpassé tous les autres types étudiés, et leur résistance peut être améliorée de façon significative par la sélection et l'optimisation de la géométrie d'assemblage.

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Copyright information

© RILEM 2001

Authors and Affiliations

  • J. G. Broughton
    • 1
  • A. R. Hutchinson
    • 1
  1. 1.Joining Technology Research CentreOxford Brookes UniversityOxfordUK

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