Analysis and design of a hybrid re-centring energy dissipation device for steel moment frames

Open circular holes with a certain size in beam web at 1/6 span is a new method to improve the seismic behavior of steel moment frames. Based on the results of elasticity theory, analytical model of frame with opening web is proposed, and analysis and verification with nonlinear finite element method (FEM) are conducted. Results show that, beam with opening web at 1/6 span can significantly reduce the axial stress of beam flange near the beam-column connections. It is helpful to achieve the design criterion of strong connection and weak member, and also to simplify the connection construction. If the diameter of web opening is appropriate, beam plastic hinges can move inward to beam section at opening web, and has little effect on bearing capacity, stiffness, energy dissipation capacity and ductility of frames. The method of web openings and the size range are presented at the end of this paper.

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Increasing Seismic Energy Dissipation of Steel Moment Frames Using Reduced Web Section (RWS) Connection

Journal of Earthquake Engineering ◽

10.1080/13632469.2016.1210057 ◽

2016 ◽

Vol 21 (7) ◽

pp. 1090-1112 ◽

Cited By ~ 4

Author(s):

Saeed Erfani ◽

Vahid Akrami

Keyword(s):

Energy Dissipation ◽

Seismic Energy ◽

Moment Frames ◽

Steel Moment Frames

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Behavior and Design Recommendations of Splice Connection in Weak-Axis Column-Tree Steel Moment Frames

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1025-1026.902 ◽

2014 ◽

Vol 1025-1026 ◽

pp. 902-905

Author(s):

Kang Min Lee ◽

Liu Yi Chen ◽

Yang Yang ◽

Keun Yeong Oh ◽

Sung Bin Hong

Keyword(s):

Energy Dissipation ◽

Plastic Hinge ◽

Moment Frames ◽

Steel Moment Frames ◽

Cross Sectional ◽

Design Recommendations ◽

Rotation Capacity ◽

Story Drift ◽

Ductility Capacity ◽

Plastic Rotation Capacity

The main objectives of this paper was to investigate the cyclic performance of splice connection in weak-axis column-tree connections with the formation of plastic hinge assumed at splice connection and provide some design recommendations. By reducing the cross-sectional area of the splice plates, the splice connection in this test are designed as a weaken component to utilize the ductility capacity and energy dissipation. The results showed that it could develop the plastic rotation capacity in the beam splice connection and portion in the link beam but not increase the energy dissipation capacity during the same story drift ratio.

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Effects of Fling Step and Forward Directivity on Seismic Response of Buildings

Earthquake Spectra ◽

10.1193/1.2192560 ◽

2006 ◽

Vol 22 (2) ◽

pp. 367-390 ◽

Cited By ~ 255

Author(s):

Erol Kalkan ◽

Sashi K. Kunnath

Keyword(s):

Seismic Response ◽

Ground Motions ◽

High Amplitude ◽

Moment Frames ◽

Steel Moment Frames ◽

Damage Potential ◽

Near Fault ◽

Forward Directivity ◽

Fling Step ◽

Far Fault

This paper investigates the consequences of well-known characteristics of near-fault ground motions on the seismic response of steel moment frames. Additionally, idealized pulses are utilized in a separate study to gain further insight into the effects of high-amplitude pulses on structural demands. Simple input pulses were also synthesized to simulate artificial fling-step effects in ground motions originally having forward directivity. Findings from the study reveal that median maximum demands and the dispersion in the peak values were higher for near-fault records than far-fault motions. The arrival of the velocity pulse in a near-fault record causes the structure to dissipate considerable input energy in relatively few plastic cycles, whereas cumulative effects from increased cyclic demands are more pronounced in far-fault records. For pulse-type input, the maximum demand is a function of the ratio of the pulse period to the fundamental period of the structure. Records with fling effects were found to excite systems primarily in their fundamental mode while waveforms with forward directivity in the absence of fling caused higher modes to be activated. It is concluded that the acceleration and velocity spectra, when examined collectively, can be utilized to reasonably assess the damage potential of near-fault records.

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