Numerical study of the robustness of steel moment connections under catenary effect

This research work presents new details for moment connections in precast concrete structures satisfying both design and practice criteria. In this paper the results of the numerical study on the connections are presented. For the analysis, the ANSYS software is selected because of its diversity in nonlinear analysis. By calculating the monotonic load-displacement curve of each connection, the connections are evaluated for their stiffness, strength, and ductility. The compressive strength of the connection concrete is taken to be 30, 35 and 40 MPa, for each round of analysis. The results of the analysis show that the proposed connections are stiff enough to be moment resisting and to be emulating an equivalent monolithic, or basic connection. It is illustrated that the connections are stronger but somewhat less ductile than the basic connection regardless of the concrete strengths examined. Moreover, it is shown that in each precast connection while increasing the compressive strength of concrete does not affect the connection stiffness considerably, it increases the ultimate load and ductility of the connection. As a main result of this study, the suggested connection details are categorized based on their stiffness, strength, and ductility. The suggested connections can be used in moment resisting precast concrete buildings based on the desired strength and ductility.

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A Finite Element Study of Non-Orthogonal Bolted Flange Plate Connections for Seismic Applications

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.763.525 ◽

2018 ◽

Vol 763 ◽

pp. 525-532 ◽

Cited By ~ 5

Author(s):

Zachary D. Hunn ◽

Gian Andrea Rassati ◽

James A. Swanson ◽

Thomas M. Burns

Keyword(s):

Numerical Study ◽

Plastic Hinge ◽

Vertical Plane ◽

Stress Distributions ◽

Moment Connections ◽

Rotation Capacity ◽

Current Design ◽

Plate Connections ◽

Bolted Flange ◽

Element Study

The current design approach for moment connections in many seismic specifications worldwide focuses on providing energy dissipation to achieve a collapse prevention objective. Most specifications only provide guidance for the design of beam-column connections in orthogonal configurations. However, it is not uncommon that for architectural reasons beams be required to frame into columns at an angle, either with respect to the horizontal (sloped connections) or with respect to a vertical plane (skewed connections), for the design of which little guidance is available. This paper presents a numerical study focusing on Bolted Flange Plate connections in non-orthogonal configurations. The response of these connections was compared to extant experimental results, using orthogonal configurations as a baseline. Investigating the connections response in terms of moment-rotation capacity, stress distributions, plastic strain demands, and plastic hinge locations, some recommendations for the design of non-orthogonal Bolted Flange Plate connections are presented. Secondarily, a study of the influence of specific details on the response of the connections was performed, resulting in practical detailing recommendations.

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Cyclic Behavior of Steel Beam-to-Column Moment Connections Using Different Sizes of Flange Plates and Reinforced by a Single Rib Plate

Civil Engineering Journal ◽

10.28991/cej-030975 ◽

2018 ◽

Vol 4 (1) ◽

pp. 138

Author(s):

Abbas Haghollahi ◽

Hassan Ahmadi

Keyword(s):

Numerical Study ◽

Plastic Hinge ◽

Equivalent Plastic Strain ◽

Cyclic Behavior ◽

Bottom Flange ◽

Moment Frames ◽

Moment Connections ◽

Element Analysis ◽

Beam Geometry ◽

Special Moment Frames

This paper presents a numerical study on the behavior of connection between steel I-beam and H-column when are affected by cyclic loading. The connection used the flange plates to connect the beam flanges to the column flange. They were welded to the top and bottom flange plates and created a welded flange plate (WFP) connection. Specimens were six models of WFP connections with different beam geometry and flange plate sizes which were modeled and their cyclic behavior were investigated using finite element analysis in ABAQUS program. Three of them were reinforced by a vertical triangular top and bottom rib plates, and others remained unreinforced. The results showed that reinforcement with a vertical triangular rib plate attached to the top and bottom flange plates can improve cyclic behavior of WFP connections. By using a rib plate, the equivalent plastic strain was increased and showed better plastic hinge formation compared to those with no vertical rib plate. Those models with IPB beam sections had the best cyclic behavior compared to those with IPE beam sections and satisfied the acceptance criteria of AISC seismic provisions for intermediate and special moment frames. We concluded that those WFP connections which did not satisfy the criteria of AISC seismic provisions for special moment frames, can be upgraded by a vertical triangular rib plate in order to be used in special moment frames.

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A NUMERICAL STUDY OF PRECAST BEAM-COLUMN MOMENT CONNECTIONS UNDER COLUMN REMOVAL SCENARIO

Journal of Al-Azhar University Engineering Sector ◽

10.21608/auej.2017.19259 ◽

2017 ◽

Vol 12 (42) ◽

pp. 175-185

Author(s):

Mariam Ehab ◽

Hamed Salem ◽

Mohamed Abdel-Mooty

Keyword(s):

Numerical Study ◽

Moment Connections ◽

Column Removal ◽

Column Removal Scenario

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Cyclic Behavior of Hollow Section Beam–Column Moment Connection: Experimental and Numerical Study

Metals ◽

10.3390/met10121608 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1608

Author(s):

Eduardo Nuñez ◽

Nwar Boainy ◽

Freddy González ◽

Ronald Torres ◽

Ricardo Picón ◽

...

Keyword(s):

Numerical Model ◽

Large Scale ◽

Numerical Study ◽

Local Buckling ◽

Cyclic Behavior ◽

Steel Buildings ◽

Moment Connections ◽

Hollow Section ◽

Moment Connection ◽

Ductile Behavior

Steel buildings with tubular columns showed a satisfactory performance during the Honshu (2011) earthquake, unlike steel buildings in the 1994 Northridge and 1995 Kobe earthquakes, where welded moment connections showed damage in their joints. In this research, a lateral joint using a hollow structural section (HSS)-beam and HSS-column subjected to cyclic displacement was performed. Three large-scale specimens were tested and a numerical model was calibrated, reaching a good adjustment. Later, several configurations of beams and columns were evaluated using finite element (FE) models from the numerical model previously calibrated. A flexural resistance higher 0.80 Mp at 0.04 [rad] was obtained for all cases studied. The ductility factor in the 3 specimens was lower than 2.5, therefore a non-ductile behavior was controlled in the connection. This aspect is very important although a 0.8 Mp at 0.04 [rad] was achieved. Finally, the typical welded moment connection can be improved using the bolted moment connection, which allows the concentration of inelastic incursion in the beam compared with the welded solution. However, a non-ductile behavior derived from local buckling in flanges of a tubular beam can affect the seismic performance.

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Cyclic Behavior of Bolted Extended End-Plate Moment Connections with Different Sizes of End Plate and Bolt Stiffened by a Rib Plate

Civil Engineering Journal ◽

10.28991/cej-030979 ◽

2018 ◽

Vol 4 (1) ◽

pp. 200 ◽

Cited By ~ 2

Author(s):

Abbas Haghollahi ◽

Reza Jannesar

Keyword(s):

Cyclic Loading ◽

Numerical Study ◽

Equivalent Plastic Strain ◽

Cyclic Behavior ◽

Moment Frames ◽

Moment Connections ◽

Element Analysis ◽

Inertia Moment ◽

End Plate ◽

Extended End Plate

This paper presents a numerical study on the behavior of prequalified Bolted Extended End Plate (BEEP) moment connections when are affected by cyclic loading. Specimens were six four-bolt extended end-plate connections consist of H-shaped columns and I-shaped beams with different geometry as well as different end-plate size and bolt diameter; three of them were stiffened by a triangular rib plate welded to the top and bottom of the beam flanges, and others remained unstiffened. They were modeled in ABAQUS software and their cyclic behavior was evaluated using finite element analysis. Responses of specimens were examined by presenting their equivalent plastic strain, stress distribution, and moment-rotation hysteretic curves. Results revealed that with the increase of beam height and inertia moment in equal story drift rotations, the reduction of connection strength occurred earlier due to the occurrence of local buckling in the beam web and flange after subjecting to cyclic loading. By comparing moment-rotation hysteretic responses of specimens, it was found out that in unstiffened BEEP connections with thinner end-plate, the use of single vertical rib stiffener can slightly improve their cyclic behavior, but in connections with thicker end plate, it showed no considerable effect. It was concluded that the BEEP connections whose dimensions are not based on the tenth code of the Iranian national building regulations, cannot satisfy the criteria of AISC seismic provisions for both special and intermediate steel moment frames, although they experienced no local beam web and flange buckling.

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