Ultimate behavior of bolted T-stubs. I: Theoretical model

The work presented in this paper represents the first step of a research ac tivity aimed at the prediction of the plastic rotation supply of partial-st rength bolted connections, starting from the knowledge of their geometrical and mechanical properties, by means of the component approach. As the main sources of plastic deformation of such connections are due to the componen ts commonly modeled by means of an equivalent T-stub, the prediction of the plastic deformation capacity of bolted T-stubs is of primary importance wi thin the framework of the component approach. Therefore, a theoretical mode l for predicting the plastic deformation capacity of bolted T-stubs is pres ented in this paper. The collapse mechanism topologies of bolted T-stubs ar e analyzed, and the corresponding formulations for predicting the ultimate value of the plastic displacement are given. Although the primary aim of th e model is the prediction of the plastic deformation capacity, it can also be used for an approximate evaluation of the whole force-displacement curve . To evaluate the accuracy of the proposed model, an experimental program h as been carried out. The experimental results and the comparison with the t heoretical predictions are presented in a companion paper, providing a sati sfactory agreement between theoretical results and experimental evidence.