Characterization of Behavior of Steel-Concrete Composite Members and Frames with Applications for Design

Denavit, Mark D.; Hajjar, Jerome F.

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https://hdl.handle.net/2142/55347 Copy

Description

Title

Characterization of Behavior of Steel-Concrete Composite Members and Frames with Applications for Design

Author(s)

• Denavit, Mark D.
• Hajjar, Jerome F.

Issue Date

2014-07

Keyword(s)

• Composite Construction
• Composite Frames
• Composite Beam-Columns
• Steel Concrete
• Nonlinear Analysis
• Load Transfer
• Stability Seismic

Abstract

Steel-concrete composite frames are seeing increased use in practice. Their excellent structural characteristics, including high strength, stiffness, and ductility, make them an appealing option for many building configurations. However, there exist gaps in the knowledge of behavior and the design provisions for these structures. This work seeks to document composite member and frame behavior and address key design issues through targeted studies utilizing advanced computational formulations and detailed examination of experimental results. A three-dimensional distributed plasticity beam finite element formulation suitable for nonlinear static and dynamic analyses of steel-concrete composite frames has been developed. The formulation is suitable for both concrete-filled steel tubes (CFT) and steel reinforced concrete (SRC) members, as well as steel wide-flange and hollow structural steel sections that are part of composite frames. A mixed basis for the formulation was chosen to allow for accurate modeling of both material and geometric nonlinearities. The formulation utilizes uniaxial cyclic constitutive relations for the concrete and steel that account for the salient features of each material, as well as the interaction between the two, including concrete confinement and local buckling. The accuracy of the formulation was verified against a wide variety of monotonic and cyclic experimental results of composite members, demonstrating the capability of the formulation to accurately produce realistic simulations of element and frame behavior. Aspects of the behavior of composite columns were assessed through an examination of results from a series of experiments on full-scale slender CFT beam-columns conducted by project collaborators. Additionally, comparative computational analyses were performed using the mixed beam formulation and detailed data interpretation focusing on the beam-column interaction strength was conducted. Several aspects of the design of steel-concrete composite structures were examined. The natural bond behavior of CFT columns was investigated through an examination of prior experimental work and new provisions were developed for the assessment of natural bond strength of CFT connections. The in-plane stability behavior of steel-concrete composite members and frames was assessed through a parametric study on small non-redundant benchmark frames, leading to the development of new elastic flexural rigidities for elastic analysis of composite members; new effective flexural rigidities for calculating the axial compressive strength of SRC members; new Direct Analysis stiffness reductions for composite members; and new recommendations for the construction of the interaction diagram for composite members. The seismic behavior of composite moment and braced frames was assessed through static pushover and incremental dynamic analyses. The analyses were performed on a suite of 60 archetype frames that were designed according to current design provisions. Connections were assumed to be strong; however, panel zone behavior for the moment frames and bond-slip behavior for SRC columns were included in the model. Using the analysis results, system performance factors were developed for the composite frames based on the methodology described in FEMA P695.

Publisher

Newmark Structural Engineering Laboratory. University of Illinois at Urbana-Champaign.

Series/Report Name or Number

Newmark Structural Engineering Laboratory Report Series 034

ISSN

1940-9826

Type of Resource

text

Language

en

Permalink

http://hdl.handle.net/2142/55347

Sponsor(s)/Grant Number(s)

This material is based upon work supported by the National Science Foundation under Grant Nos. CMMI-0619047 and CMMI-0530756 as part of the George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES); the American Institute of Steel Construction; the Georgia Institute of Technology; and the University of Illinois at Urbana-Champaign. Computational analyses in this work were executed in part on the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation Grant No. OCI-1053575. Any opinions, findings, and conclusions expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation or other sponsors.

Copyright and License Information

Copyright held by the authors. All rights reserved.

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