Performance Evaluation of Friction Damped Braced Steel Frames under Simulated Earthquake Loads

This paper presents the results obtained from tests of a new friction damping system, which has been proposed in order to improve the response of steel Moment Resisting Frames (MRF) and Braced Moment Resisting Frames (BMRF) during severe earthquakes. The system consists of a mechanism containing brake lining pads introduced at the intersection of frame cross-braces. Seismic tests of a three storey Friction Damped Braced Frame (FDBF) model were performed on an earthquake simulator table. The experimental results are compared with the findings of an inelastic time-history dynamic analysis. The results clearly indicate the superior performance of the FDBF compared to conventional building systems.

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Seismic fragility of steel moment-resisting frames in Vancouver and Montreal designed in the 1960s, 1980s, and 2010

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2014-0492 ◽

2015 ◽

Vol 42 (11) ◽

pp. 919-929 ◽

Cited By ~ 2

Author(s):

Lucía Valentina Díaz Gómez ◽

Oh-Sung Kwon ◽

Mohammad Reza Dabirvaziri

Keyword(s):

Numerical Models ◽

Fragility Curves ◽

Time History ◽

Steel Moment Resisting Frames ◽

Moment Resisting Frames ◽

Nonlinear Time History Analyses ◽

Moment Resisting ◽

The 1960S ◽

Steel Mrfs ◽

Nonlinear Time History

Typical steel moment-resisting frames (MRF) of six-storey buildings in Vancouver and Montreal were designed for three different provisions of the National Building Code of Canada (1960s, 1980s, and 2010). Numerical models were developed in OpenSees to understand the seismic performance of the structures. These models accounted for strength and stiffness degradation through appropriate representations of the beam–column connection behaviours, which were calibrated against experimental results available in the literature. The behaviour of the buildings was evaluated through pushover and nonlinear time history analyses. The pushover analysis results showed that the 1960s and 2010 steel MRFs of both cities exhibited strong-column-weak-beam failure mode. The 1980s steel MRFs of both cities showed soft-storey mechanism. Fragility curves were developed for the steel MRFs based on the seismic demands evaluated using nonlinear time history analyses, which can be used for regional seismic impact assessment studies in the future.

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Amplified Seismic Loads in Steel Moment Frames

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.847.222 ◽

2016 ◽

Vol 847 ◽

pp. 222-232

Author(s):

Bora Aksar ◽

Selcuk Dogru ◽

Bulent Akbas ◽

Jay Shen ◽

Onur Seker ◽

...

Keyword(s):

Lateral Displacement ◽

Ground Motions ◽

Time History ◽

Load Level ◽

Steel Buildings ◽

Moment Frames ◽

Axial Loads ◽

Steel Moment Resisting Frames ◽

Moment Resisting Frames ◽

Moment Resisting

This study focuses on exploring the seismic axial loads for columns in steel moment resisting frames (SMRFs) under strong ground motions. For this purpose, the increases in axial loads are investigated at the maximum lateral load level and the corresponding lateral displacement. The results are presented in terms of maximum amplification factors (Ω0) of all frame columns under the selected ground motions and axial load-moment levels in columns. four typical steel moment resisting frames representing typical low, medium and high rise steel buildings are designed based on the seismic design requirement in ASCE 7-10 and AISC 341-10 . An ensemble of ground motions range from moderate to severe are selected to identify the seismic response of each frames. Two sets of ground motions corresponding to 10% and 2% probability of exceedance are used in nonlinear dynamic time history analyses.

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Seismic Upgrading of Steel Moment-Resisting Frames by Means of Friction Devices

The Open Construction and Building Technology Journal ◽

10.2174/1874836801408010289 ◽

2014 ◽

Vol 8 (1) ◽

pp. 289-299 ◽

Cited By ~ 5

Author(s):

Esra Mete Güneyisi ◽

Mario D'Aniello ◽

Raffaele Landolfo

Keyword(s):

Structural Response ◽

Time History ◽

Seismic Behaviour ◽

Steel Moment Resisting Frames ◽

Residual Drift ◽

Moment Resisting Frames ◽

Drift Ratio ◽

Nonlinear Time History Analyses ◽

Moment Resisting ◽

Nonlinear Time History

In recent decades, several passive energy dissipation systems have been conceived in order to minimize the damage in structural and non-structural components of either new or existing buildings. In this study, the use of friction damped tension-compression diagonal braces for seismic upgrading of a steel moment resisting frames is investigated. To this aim, nonlinear time history analyses have been carried out on a set of representative frames with and without friction damped braces. In the nonlinear time history analyses, two sets of natural accelerograms compatible with seismic hazard levels of 10% and 2% probability of exceedance in 50 years have been considered. Under these records, the structural response has been comparatively investigated in terms of the maximum inter-storey drift ratio, maximum storey acceleration, residual drift ratio and displacement demand for the friction device. The results clearly highlighted that the application of friction damped braces allows reducing the damages to the main structural elements, thus significantly improving the seismic behaviour of the frame.

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Effect of Column Base Behavior on Seismic Performance of Multi-Story Steel Moment Resisting Frames

International Journal of Structural Stability and Dynamics ◽

10.1142/s0219455419400078 ◽

2018 ◽

Vol 19 (01) ◽

pp. 1940007 ◽

Cited By ~ 1

Author(s):

Yao Cui ◽

Fengzhi Wang ◽

Satoshi Yamada

Keyword(s):

Plastic Deformation ◽

Local Buckling ◽

Time History ◽

Thickness Ratio ◽

Nonlinear Time History Analysis ◽

Steel Moment Resisting Frames ◽

Moment Resisting Frames ◽

Moment Resisting ◽

The Moment ◽

Column Base

Column base is one of the most important elements of steel structures. Exposed column base is commonly used in low-to-medium-rise steel moment resisting frames because of better constructability and low cost. To study the effect of exposed column base behavior on the seismic behavior of low-to-medium-rise steel moment resisting frames, a four-story, four-bay steel moment frame is studied by the nonlinear time history analysis. In the numerical analysis, two types of column base connections (rigid and semi-rigid) are considered. The width–thickness ratio of column and stiffness ratio of column base to column are chosen as the analysis parameters. The characteristics of structural responses, hysteresis loops, and the distribution of plastic energy dissipation are compared. It indicates that the collapse margin ratio is significantly increased when the exposed column base behavior is considered for the moment resisting frames with large width–thickness ratio. Moreover, if the column base connection is allowed to rotate and transfer a portion of the moment, the demand of plastic deformation capacity of steel columns is reduced, then subsequently strength deterioration caused by the local buckling at the bottom of column could be avoided. Also, the whole structure has a better ductility, the ability of plastic deformation and energy absorbance of the moment resisting frame under earthquake are therefore enhanced. The structure with the semi-rigid column base connection has larger potential to avoid the structural collapse caused by the local buckling of first-story columns.

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