Axial stiffness prediction of non-preloaded T-stubs: An analytical frame approach

Analytical frame approach for the rotational stiffness prediction of beam-to-column angle connections

“…For the recently proposed frame approaches [13,14], a 2D representation of the T-stub problem was adopted. The idealization suggested by Annex J of Eurocode 3 consists in modelling the top angle as a bolted Tstub whose width is equal to half of its geometrical width.…”

“…The frame problems were solved by matrix structural analysis assuming linear and elastic material and small displacements. The solution for the T-stub axial stiffness relating to non-preloaded T-stubs [13] was expressed as…”

“…Faella et al [10] had proposed the evaluation of the effective width for stiffness calculations considering an equivalent cantilever whose section was based on a 45°spreading of the concentrated action due to the bolts, starting from the bolt edge. In recent research, two proposals, based on finite element parametric studies, have been suggested to evaluate the T-stub effective width relating to stiffness calculations [13,14]. These approaches, introduced in the analytical frame solutions described in Section 2, have been validated by comparisons with the experimental results from Faella et al [10] and Bursi and Jaspart [15] for preloaded and non-preloaded T-stubs, proving to be satisfactory in most cases.…”

“…In order to achieve a mechanical proposal that takes into account compatibility requirements, prying forces and bolt elongation, but preserving simplicity, an equivalent frame representing the T-stub has been lately proposed, both in non-preloaded [13] and preloaded [14] cases. These models include an effective width for stiffness calculation based on plate finite element parametric studies.…”

New proposals on the calculation of the flexural resistance in angle connections

“…This force increases the axial tension in the bolts, and reduces the load that can be safety applied to the connection [14,10].…”