A performance-based design approach for retrofitting regular building frames with steel braces against sudden column loss

Abstract Progressive collapse resistance of existing building structures against sudden column loss may be increased with adequate supply of steel braces. A performance-based design approach for retrofitting regular building frames with steel braces is proposed in this study. The retrofit design approach is developed from the pseudo-static response analysis of an idealized elastic–plastic, single degree-of-freedom system. Analytical relationship between the increment of collapse resistance and structural characteristics is derived to determine the design strength and stiffness of added braces. Accuracy of the proposed approach is verified with incremental dynamic analysis. Also, its application to multi-story buildings is demonstrated with three frame models. Conservative performance is obtained with the design approach, especially for a larger resistance increment. An iterative modification technique is suggested to refine the retrofit design and only a few nonlinear static iterations are required for convergence. Nonlinear dynamic analysis results indicate that the column-loss response of the braced frames is approximated to the performance target and thus the proposed retrofit design approach is feasible for practical applications.

[1]  Kyungkoo Lee,et al.  Simplified nonlinear progressive collapse analysis of welded steel moment frames , 2009 .

[2]  Norbert J. Delatte,et al.  Ronan Point Apartment Tower Collapse and its Effect on Building Codes , 2005 .

[3]  Young-Ho Lee,et al.  Progressive collapse resisting capacity of braced frames , 2008 .

[4]  Jinkoo Kim,et al.  Fragility analysis of steel moment frames with various seismic connections subjected to sudden loss of a column , 2010 .

[5]  Jinkoo Kim,et al.  Assessment of progressive collapse-resisting capacity of steel moment frames , 2009 .

[6]  David A. Nethercot,et al.  Progressive collapse of multi-storey buildings due to sudden column loss — Part I: Simplified assessment framework , 2008 .

[7]  Donald O. Dusenberry,et al.  Best Practices for Reducing the Potential for Progressive Collapse in Buildings | NIST , 2007 .

[8]  Feng Fu,et al.  3-D nonlinear dynamic progressive collapse analysis of multi-storey steel composite frame buildings — Parametric study , 2010 .

[9]  Khaled Galal,et al.  Effect of retrofit strategies on mitigating progressive collapse of steel frame structures , 2010 .

[10]  Fahim Sadek,et al.  Progressive collapse analysis of seismically designed steel braced frames , 2009 .

[11]  Meng-Hao Tsai,et al.  Investigation of progressive collapse resistance and inelastic response for an earthquake-resistant RC building subjected to column failure , 2008 .

[12]  Qiang Xie,et al.  State of the art of buckling-restrained braces in Asia , 2005 .

[13]  Santiago Pujol,et al.  A new perspective on the effects of abrupt column removal , 2009 .

[14]  Jinkoo Kim,et al.  BEHAVIOR AND DESIGN OF STRUCTURES WITH BUCKLING-RESTRAINED BRACES , 2004 .

[15]  M. M. Alinia,et al.  Effect of tension bracing on the collapse mechanism of steel moment frames , 2009 .

[16]  Meng-Hao Tsai,et al.  An analytical methodology for the dynamic amplification factor in progressive collapse evaluation of building structures , 2010 .

[17]  Dipti Ranjan Sahoo,et al.  PERFORMANCE-BASED PLASTIC DESIGN METHOD FOR BUCKLING RESTRAINED BRACED FRAMES , 2010 .

[18]  Osama Ahmed Mohamed Assessment of progressive collapse potential in corner floor panels of reinforced concrete buildings , 2009 .

[19]  Sashi K. Kunnath,et al.  Macromodel-Based Simulation of Progressive Collapse: Steel Frame Structures , 2008 .

[20]  J. L. Liu Preventing progressive collapse through strengthening beam-to-column connection, Part 1: Theoretical analysis , 2010 .