Component-based mechanical models for axially-loaded through-diaphragm connections to concrete-filled RHS columns

• A component-based model to predict the load–deformation response.
• Contribution of membrane action and strain hardening was considered and quantified.
• The hand calculation of yield and ultimate deformation was developed.
• Good agreement was obtained between experimental results and predicted model.

This paper presents the results of theoretical studies into the behavior of the through-diaphragm to concrete-filled rectangular hollow section (RHS) columns subjected to tensile force. Component-based models have been developed and used for predicting the strength of the column component of concrete-filled RHS columns under tensile load imparted through a through-diaphragm connection. The strength models are based upon defining a rigid plate deformation pattern for the column face and then applying the virtual work principle, taking into account the membrane action and strain hardening. The hand calculation procedures for yield and ultimate deflection were also developed. The load–deformation curve consists of three segments: the first representing the elastic behavior from the classic plate theory, the second obtained by plotting the deformation at the ultimate strength against the maximum load, and the third a horizontal line stretching to the failure point. The mechanical models were compared with a large range of experimental results and good agreement was shown between them. The proposed method can be used in the component-based method for connections involving a through-diaphragm component in tension.