Behavior of dowelled and bolted steel-to-timber connections exposed to fire

Abstract This study focuses on the load distributions among fasteners in steel-to-timber connections loaded in tension parallel-to-grain under fire exposure. The experimental results of some types of connections with various geometrical configurations are available. The influence of the type of fasteners (bolt, dowel) on the thermo-mechanical behavior of the connections is studied. A three-dimensional finite element model validated on the basis of experimental results is used. Good agreements were observed between the simulated and the experimental values of temperatures and failure times. The type of metal fasteners is crucial to the thermo-mechanical behavior of connections. In the studied connections, one bolt is used in each row of fasteners to prevent the separation between the assembled members. The presence of the bolts greatly influences the behavior of the connections mainly under fire. Various geometrical configurations of connections with only dowels or changing the positions of the bolts are studied. An analytical approach is proposed, from a specific type of connections, by varying some influent geometrical characteristics. A numerical experimental design is realized from the calculated time to failure of the connections.

[1]  Thomas Lee Wilkinson.  Load Distribution among Bolts Parallel to Load , 1986 .

[2]  E. Gaylord,et al.  Design of Steel Structures , 1972 .

[3]  Ulf Wickström,et al.  Comments on calculation of temperature in fire-exposed bare steel structures in prEN 1993-1-2: Eurocode 3—design of steel structures—Part 1–2: general rules—structural fire design , 2005 .

[4]  Abdelhamid Bouchaïr,et al.  Thermo-mechanical analysis of the fire performance of dowelled timber connection , 2010 .

[5]  Chanakya Arya,et al.  Design in timber to BS 5268 , 2009 .

[6]  H. J. Larsen,et al.  DS/ENV 1995-1-1 NAD National Application Document for Eurocode 5: Design of Timber Structures, Part 1-1: General Rules and Rules for Buildings , 1994 .

[7]  M. Taazount,et al.  Numerical investigations on the thermo-mechanical behavior of steel-to-timber joints exposed to fire , 2011 .

[8]  A. Vergne,et al.  Effet des conditions aux limites sur le comportement des assemblages bois boulonnés , 1996 .

[9]  P. Racher,et al.  Analysis of dowelled timber to timber moment-resisting joints , 2007 .

[10]  Jean-François Bocquet.  Modelisation des deformations locales du bois dans les assemblages broches et boulonnes , 1997 .

[11]  Andrew H. Buchanan.  Fire performance of timber construction , 2000 .

[12]  Karine Laplanche.  Etude du comportement au feu des assemblages de structures bois : approche expérimentale et modélisation , 2006 .

[13]  Marie Johansson,et al.  Design of Timber Structures , 2011 .

[14]  M. Taazount,et al.  Numerical and experimental analyses of multiple-dowel steel-to-timber joints in tension perpendicular to grain , 2009 .

[15]  G. Lantos.  Load distribution in a row of fasteners subjected to lateral load , 1969 .