Probabilistic evaluation of global seismic capacity of degrading structures

The present study addresses the probabilistic seismic capacity evaluation of the existing non-ductile reinforced concrete structures that are vulnerable to shear, and thus axial, failures of their columns. The probability of structural collapse at a target lateral displacement imposed by seismic hazard is estimated by reliability analysis. For this purpose, the prevalent nonlinear static procedure is extended with finite element reliability analysis. The global structural model is enhanced by incorporating probabilistic capacity and post-failure response models of individual columns. The challenges in the detection of collapse and the potential problems and remedies in the reliability analysis due to ‘gradient discontinuities’ are presented. In particular, ‘smoothing’ of the post-failure response models is implemented to represent realistic member behaviour and to avoid non-convergence in the reliability analysis. Finally, parameter importance measures are employed to identify the parameters with the highest contribution to the uncertainty in the structural performance. Copyright © 2007 John Wiley & Sons, Ltd.

[1]  Armen Der Kiureghian,et al.  Strategies for finding the design point in non-linear finite element reliability analysis , 2006 .

[2]  R. Rackwitz,et al.  Sensitivity and importance measures in structural reliability , 1986 .

[3]  Armen Der Kiureghian,et al.  Probabilistic Capacity Models and Fragility Estimates for Reinforced Concrete Columns based on Experimental Observations , 2002 .

[4]  Steen Krenk,et al.  Parametric Sensitivity in First Order Reliability Theory , 1989 .

[5]  Jack P. Moehle,et al.  Drift Capacity of Reinforced Concrete Columns with Light Transverse Reinforcement , 2005 .

[6]  Kuo-Chun Chang,et al.  Comparison of displacement coefficient method and capacity spectrum method with experimental results of RC columns , 2004 .

[7]  R. Goel,et al.  Evaluation of NSP to Estimate Seismic Deformation: SDF Systems , 2000 .

[8]  Peter Fajfar,et al.  Capacity spectrum method based on inelastic demand spectra , 1999 .

[9]  Kenneth J. Elwood,et al.  Modelling failures in existing reinforced concrete columns , 2004 .

[10]  Anil K. Chopra,et al.  A modal pushover analysis procedure for estimating seismic demands for buildings , 2002 .

[11]  Santiago Pujol,et al.  Drift capacity of reinforced concrete columns subjected to displacement reversals , 2002 .

[12]  Jack P. Moehle,et al.  Axial Capacity Model for Shear-Damaged Columns , 2005 .

[13]  Joel P. Conte,et al.  Finite element structural response sensitivity and reliability analyses using smooth versus non-smooth material constitutive models , 2006 .

[14]  Henrik O. Madsen,et al.  Structural Reliability Methods , 1996 .

[15]  A. Kiureghian,et al.  Parameter sensitivity and importance measures in nonlinear finite element reliability analysis , 2005 .