Postelastic Behavior of Single- and Double-Bolt Timber Connections
Publication: Journal of Structural Engineering
Volume 131, Issue 1
Abstract
A nonlinear numerical model is developed to study the behavior of single- and double-bolted timber connections with relatively low member thickness-to-fastener diameter ratios. These structural joints tend to fail in a brittle fashion. Nonlinear geometry due to increased sliding contact between the bolt and the hole is modeled using the Lagrange multiplier algorithm. A plasticity-based constitutive compressive material model is developed to predict the nonlinear wood behavior in the contact zone(s). Numerical simulations of postelastic deformations of one- and two-bolt connections are compared to experimental results from tensile tests undertaken on double shear steel to glued-laminated-timber to steel connections. The established model is capable of tracing the inelastic deformations locally and globally and predicting unequal load fractions that are transferred by each bolt in two-bolt connections. Connection capacities estimated with the new elastoplastic model are bounded by classical elastic and fully plastic model predictions. Implementation of the new model is via finite element approximation representations.
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Acknowledgments
The work was carried out with financial assistance from the Natural Sciences and Engineering Research Council of Canada (NSERC), the Canadian Wood Council, and participating universities. Work reported is part of the completed NSERC Collaborative Grant Project “Failure mechanisms for structural connections in wood-fibre composites” led by Professor Ian Smith, University of New Brunswick. All new experiments were carried out at the Structure Laboratory of the Royal Military College of Canada (RMC), Kingston, Ontario according to an experimental design by the first writer and with assistance from Dr. Mohammad Mohammad from RMC (now Forintek Canada Corp., Sainte-Foy, Quebec).
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 131 • Issue 1 • January 2005
Pages: 188 - 196
Copyright
© 2004 ASCE.
History
Received: Nov 4, 2002
Accepted: Jun 9, 2004
Published online: Jan 1, 2005
Published in print: Jan 2005
Notes
Note. Associate Editor: Daniel Dolan
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