Collapse Prevention Seismic Performance Assessment of New Special Concentrically Braced Frames using ASCE 41

Area of Science:

• Structural Engineering
• Earthquake Engineering
• Seismic Performance Assessment

Background:

• Special Concentrically Braced Frames (SCBFs) are critical seismic force-resisting systems.
• Building codes like the International Building Code (IBC) and standards such as ASCE 7 and ASCE 41 guide seismic design and assessment.
• Understanding the correlation between design (ASCE 7-10) and assessment (ASCE 41-06) standards is crucial for accurate seismic performance evaluation.

Purpose of the Study:

• To evaluate the seismic performance of SCBFs designed per the 2012 IBC using ASCE 41-06.
• To investigate the correlation between seismic performance predicted by ASCE 7-10 and ASCE 41-06.
• To identify factors contributing to performance discrepancies and recommend improvements.

Main Methods:

• Designed three archetype buildings (4-, 8-, 16-story) with SCBFs.
• Utilized Equivalent Lateral Force (ELF) and Response Spectrum Analysis (RSA) procedures for seismic design.
• Conducted linear and nonlinear static and dynamic analyses for performance assessment per ASCE 41-06.

Main Results:

• Linear analyses showed minor column issues and no brace issues.
• Nonlinear analyses indicated consistent failure of SCBF braces to meet ASCE 41-06 assessment criteria.
• Discrepancies were observed between performance anticipated by ASCE 7-10 and ASCE 41-06.

Conclusions:

• Nonlinear analysis is essential for identifying critical brace performance issues in SCBFs.
• Current ASCE 41-06 criteria may not fully capture the seismic demands on SCBF braces.
• Recommendations include using advanced ground motion selection, higher fidelity brace models, and ductility/energy-based acceptance criteria for improved seismic assessment.