Abstract
The 2008 Wenchuan-China earthquake showed the importance of considering the bidirectional seismic action as a cause of failure in column hinge mechanisms. Subsequently, the large 2011 Tohoku-Japan earthquake revealed that Special Moment Frames buildings, made of tubular columns (Hollow Structural Section or Built-up Box Section) and rigid connections with I-beams, did not suffer serious damage. However, only the ConXtech® ConXL™ moment connection has been prequalified according to the (American Institute of Construction) AISC Seismic Provisions for use with tubular columns and the rest of connections do not consider biaxial resistance. The research reported herein investigated the cyclic response of box-columns joints, connected to I beams using the four-bolt extended endplate connection, subjected to bidirectional bending and axial load on the column. To conduct the study, complex nonlinear finite element models (FEMs) of several I beam to box column joint configurations were constructed and analyzed under cyclic loading using the ANSYS software. The results reveal that the failure is concentrated in the beams of all joint configurations except for the columns with axial load equal to 75% of the column capacity, where a combined failure mechanism is achieved. The energy dissipation capacity of joints with a greater number of beams is lower than joints with fewer beams. The bidirectional effect of the seismic action and the level of axial load must be considered to avoid the formation of a column-hinge fragile failure mechanism also the behavior exhibited by 3D joints is more realistic than 2D joints according to real structures.
Highlights
The 2008 Wenchuan China Earthquake evidenced the importance to consider bidirectional seismic action in the performance of columns and its incidence in the failure mechanism [1]
Metals 2020, 10, 523 restraints about the principle axes, a rectangular tube can be selected with proportions that provide the same column slenderness ratio about the major and minor axes, thereby providing the most efficient use of material, (ii) the torsional stiffness of the closed shape and the high weak axis moment of inertia minimize the requirements for lateral bracing of tubular beams and (iii) significant ductility for post-Northridge connections is sometimes provided by panel zone yield deformation, but excess panel zone deformation causes a potential for early connection fracture due to excess local inelastic deformation
This paper describes the research conducted to study the cyclic response of end-plate moment connections between wide flange beams and box columns
Summary
The 2008 Wenchuan China Earthquake evidenced the importance to consider bidirectional seismic action in the performance of columns and its incidence in the failure mechanism [1]. A recent research conducted by [10], performed an analytical, numerical and experimental study of and end-plate moment connection between a wide flange beam and a hollow structural section column (EP-HSS). An experimental research involving the testing of ten full-scale moment resisting connections with wide flange beam to square concrete filled steel tube column under simulated seismic loading conditions was performed by [13]. This paper describes the research conducted to study the cyclic response of end-plate moment connections between wide flange beams and box columns For this purpose, numerical models of end-plate moment connections, that were calibrated from previous tests [10], were generated for different joint configurations expanding to 3D joints, 2D joints and several levels of axial load. Previous research has focused on welded connections between wide flange beam and tubular column (hollow structural section or Box section), tubular beam to tubular column (welded for this type) and wide flange beam to wide flange column (welded and bolted for this type)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
