Double shear bolted bracket moment connections, part 2: Four-bolt configuration response evaluation: Fid-Bau Portal

Double shear bolted bracket moment connections, part 2: Four-bolt configuration response evaluation

Mirzaie Abar, Bahram / PhD Ghobadi, Mohammad Soheil / PhD Ahmady Jazany, Roohollah

Abstract The design methodology of a new Double Shear Bolted Bracket (DSBB) moment connection was introduced in Part I of this research. The DSBB connection is a bolted bracket connection that profits from double shear performance of stem bolts. In Part II of this research, a response evaluation is conducted by designing and modeling various parametric study specimens to evaluate the efficiency of the proposed design method. In the finite element modeling of the parametric study specimens, the adequacy of size and thickness of the bracket flanges, stems, and stiffeners, and the adequacy of bolt diameter of the bolted bracket are evaluated. In order to check the qualification of the DSBB connection based on AISC 358–18 connection code criteria, the double-tee and end-plate prequalified moment connections in the aforementioned code are also considered as reference connections beside the DSBB connection. For all specimens, the cyclic responses are provided and compared. In the following, the energy dissipation in the beam and connection of the specimens is compared. Eventually, stress state indices including rupture index and plastic equivalent strain index, in the defined critical lines and points of all specimens are calculated and discussed. Comparing the performance of the DSBB connection specimens with the end-plate and double-tee connections indicates that the risk of failure, concentration of stresses and strains, and out of plane and buckling deformations in the DSBB connection are less than that of the prequalified end-plate and double-tee connections; therefore, DSBB can be a qualified moment connection.

Graphical abstract Display Omitted

Highlights • The hysteresis curve of the DSBB connection indicates ideal and efficient performance. • The total energy dissipation of the DSBB connection happened in beam plastic hinge. • The damage probability in the protected zone of the DSBB connection is almost zero. • The failure risk in the DSBB bolts is lesser than the prequalified end-plate connection. • The failure risk in the DSBB bolts is lesser than the prequalified double-tee connection.