Modelling of unstiffened flush end-plate bolted connections in fire

The present paper studies the behaviour of flush end-plate bare-steel connections at elevated temperatures using the general purpose finite element software ABAQUS. The finite element model was used to establish the moment–rotation characteristics of the connections under the combined loading of a concentrated force and elevated temperature. The connection components were modelled using three-dimensional brick elements, while contact between the various components was modelled using Coulomb friction. Materials for steel members and connection components were considered to behave nonlinearly. Degradation of steel properties with increasing temperature was assumed in accordance with EC3 recommendations. Finite element results and experimental tests conducted on flush end-plate connection in fire conditions were compared, and these showed good agreement. The obtained simulated failure modes and moment–rotation–temperature characteristics of the connections compared well with the experimental data.