Simplified probabilistic seismic assessment of RC frames with added viscous dampers

Abstract The object of this paper is the study of simplified probabilistic procedures for the seismic assessment of nonlinear structures equipped with nonlinear fluid viscous dampers. The considered reference probabilistic approach is the SAC-FEMA method, which allows to obtain the probability of exceeding a given performance level. The specific purpose is to study the correlation between the results obtained through the probabilistic seismic assessment method for structures with and without dampers, with emphasis on these results in terms of dispersion. A wide set of recorded ground motions was therefore selected and applied to the considered RC frames. The study was performed without applying scaling factors to the earthquake records, but by selecting different sets of records for increasing values of seismic intensity. All the obtained results were examined considering different criteria, in order to determine the set of time-history analyses to be used for the probabilistic evaluation. Different methods were then applied to obtain the dispersion of the seismic demand. With reference to the application of the SAC-FEMA method, a sensitivity analysis was also performed, considering different procedures to interpolate the hazard curve. From the analyses, it was possible to derive the expressions that allow the results for structures with and without dampers to be correlated, as well as to offer suggestions for applying the SAC-FEMA method. A second purpose of the paper is to propose and apply, in the probabilistic assessment, a direct procedure. This procedure was recently presented by some of the authors as a method to be used for obtaining the response of nonlinear structures with nonlinear viscous dampers as an alternative to expensive nonlinear dynamic analyses.

[1]  Iunio Iervolino,et al.  REXEL: computer aided record selection for code-based seismic structural analysis , 2010 .

[2]  M. Fardis,et al.  Deformations of Reinforced Concrete Members at Yielding and Ultimate , 2001 .

[3]  J. Bommer,et al.  COMPATIBLE ACCELERATION AND DISPLACEMENT SPECTRA FOR SEISMIC DESIGN CODES , 1999 .

[4]  Luca Landi,et al.  A Methodology for the Direct Assessment of the Damping Ratio of Structures Equipped with Nonlinear Viscous Dampers , 2012 .

[5]  Luca Landi,et al.  Effectiveness of different distributions of viscous damping coefficients for the seismic retrofit of regular and irregular RC frames , 2015 .

[6]  W. J. Hall,et al.  Recommended Seismic Design Criteria for New Steel Moment-Frame Buildings , 2001 .

[7]  Tomaso Trombetti,et al.  On the dimensioning of viscous dampers for the mitigation of the earthquake-induced effects in moment-resisting frame structures , 2013, Bulletin of Earthquake Engineering.

[8]  Gian Michele Calvi,et al.  Developing Direct Displacement-Based Procedures for Simplified Loss Assessment in Performance-Based Earthquake Engineering , 2014 .

[9]  T. T. Soong,et al.  Passive Energy Dissipation Systems for Structural Design and Retrofit , 1998 .

[10]  Tomaso Trombetti,et al.  Force reduction factor for building structures equipped with added viscous dampers , 2013, Bulletin of Earthquake Engineering.

[11]  C. Allin Cornell,et al.  Probabilistic Basis for 2000 SAC Federal Emergency Management Agency Steel Moment Frame Guidelines , 2002 .

[12]  Dimitrios Vamvatsikos,et al.  Derivation of new SAC/FEMA performance evaluation solutions with second‐order hazard approximation , 2013 .

[13]  J. Douglas,et al.  Internet site for European strong-motion data , 2004 .

[14]  Peter Fajfar,et al.  Simplified probabilistic seismic performance assessment of plan‐asymmetric buildings , 2007 .

[15]  Keith Porter,et al.  An Overview of PEER's Performance-Based Earthquake Engineering Methodology , 2003 .

[16]  Fabio Mazza,et al.  Control of the earthquake and wind dynamic response of steel‐framed buildings by using additional braces and/or viscoelastic dampers , 2011 .

[17]  Luca Landi,et al.  A two‐step direct method for estimating the seismic response of nonlinear structures equipped with nonlinear viscous dampers , 2014 .

[18]  Timothy J. Sullivan,et al.  Towards a simplified Direct DBD procedure for the seismic design of moment resisting frames with viscous dampers , 2012 .

[19]  Stefano Sorace,et al.  Seismic Protection of Frame Structures by Fluid Viscous Damped Braces , 2008 .

[20]  Andrea Benedetti,et al.  Displacement-Based Design of an Energy Dissipating System for Seismic Upgrading of Existing Masonry Structures , 2014 .

[21]  Luca Landi,et al.  A procedure for the direct determination of the required supplemental damping for the seismic retrofit with viscous dampers , 2014 .