A Component Approach to Modelling Steelwork Connections in Fire: Behaviour of Column Webs in Compression

Abstract

This paper outlines some of the main results in an ongoing project aimed at developing hightemperature models for the behaviour of the main components of steel end-plate beam-tocolumn connections in fire. In this particular phase of the work the emphasis is on the compression zone in the column web, when transverse compression acts concurrently with axial compression due to superstructure loading. The ultimate objective is to be able to construct component-based models of end-plate connections within global numerical modelling of steel and composite building structures in fire conditions. This is the only feasible analytical approach to connection modelling under the simultaneous effects of loading, thermal degradation of materials and forces due to restraint to thermal expansion. A simplified semi-empirical model has been validated against ANSYS modelling and isothermal high-temperature experiments.

Performance of beam-to-column joints in fire—A review

“…1). Block et al [19,20] further developed the work on the compression zone, conducting over tests at elevated temperatures and refining the analytical model for this zone. Lou and Li [21] recently reported the results of two cruciform tests conducted on 16 mm thick extended end plates with M20 bolts under ISO834 fire curve conditions.…”

Parametric study and analytical characterization of the bolt–column (BC) joint for single-layer reticulated structures

“…By assembling the contributions of individual components that represent the joint as a set of rigid and deformable elements, the entire behaviour of the joint may be determined. Based on the component method, the initial stiffness and ultimate capacity of each component is determined and assembled to form a spring model for some beam-to-column joints [11][12][13][14]. In the model, the joint components are treated as springs with predefined characteristics such as initial stiffness and ultimate capacity.…”

Experimental study and spring-component modelling of extended end-plate joints in fire

“…Each zone of the joint can be further divided into a number of components, each of which is simply a nonlinear spring, possessing its own strength and stiffness in flexure, tension, compression or shear, and will be reduced with elevation of temperature. For each component, the initial stiffness and ultimate capacity is determined and assembled to form a spring model [15], which is adopted to simulate the rotational behaviour of the whole joint. An idealised representation of the extended end-plate bare-steel joint is shown in Fig.…”