Design of steel-wood-steel connections at the ambient and elevated temperature

Document Type : Research Paper


Department of Mechanical Engineering, Insituto Politécnico do Porto. ISEP, Instituto Superior de Engenharia do Porto, 4249-015 Porto, Portugal


The goal of this work is to study steel-wood-steel (S-W-S) connections in double shear with steel dowels submitted to fire. The design at the ambient temperature was based in Eurocode 5 part 1-1 to determine the number of dowels required based on the connection characteristics. To analyze the influence of these characteristics, connections with dowels diameters with 6, 8, 10 and 12 mm, wood type GL20h, GL24h, GL28h and GL32h and the applied load of 10, 15 and 20 kN were studied. The design at the elevated temperatures was based on the Eurocode 5 part 1-2 and Eurocode 3 part 1-2, to obtain the protection thickness required for fire safety. The protection materials used were the glued laminated timber (Glulam) and type F gypsum plasterboard. The analysis of different parameters and how they influence the connection, was studied clearly using the finite element method. The temperature field allows to determine the char layer in the connections with different wood densities, when unprotected, and compare the protection efficiency with two different types of materials. As conclusion, decreasing the dowels diameter and increasing the applied load, the number of the dowels will increase. With the increasing of the dowel diameters and the wood density, it is possible to observe that the fire capability in the S-W-S connections increases.


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Volume 52, Issue 1
March 2021
Pages 85-101
  • Receive Date: 21 December 2020
  • Revise Date: 20 January 2021
  • Accept Date: 21 January 2021