A method for the direct estimation of floor acceleration spectra for elastic and inelastic MDOF structures

Summary This paper deals with floor acceleration spectra, which are used for the seismic design and assessment of acceleration-sensitive equipment installed in buildings. In design codes and in practice, not enough attention has been paid to the seismic resistance of such equipment. An ‘accurate’ determination of floor spectra requires a complex and quite demanding dynamic response history analysis. The purpose of the study presented in this paper is the development of a direct method for the determination of floor acceleration spectra, which enables their generation directly from the design spectrum of the structure, by taking into account the structure's dynamic properties. The method is also applicable to inelastic structures, which can greatly improve the economic aspects of equipment design. A parametric study of floor acceleration spectra for elastic and inelastic single-degree-of-freedom (SDOF) and multiple-degree-of-freedom structures was conducted by using (non)linear response history analysis. The equipment was modelled as an elastic single-degree-of-freedom system. The proposed method was validated by comparing the results obtained with the more accurate results obtained in a parametric study. Due to its simplicity, the method is an appropriate tool for practice. In the case of inelastic structural behaviour, the method should be used in combination with the N2 method, or another appropriate method for simplified nonlinear structural analysis. Copyright © 2016 John Wiley & Sons, Ltd.

[1]  Vladimir Vukobratović.  The influence of nonlinear seismic response of structures on the floor acceleration spectra , 2015 .

[2]  Gaetano Manfredi,et al.  Seismic demand on light acceleration‐sensitive nonstructural components in European reinforced concrete buildings , 2015 .

[3]  José I. Restrepo,et al.  Earthquake‐induced floor horizontal accelerations in buildings , 2002 .

[4]  Mahendra P. Singh,et al.  Seismic Design Forces. II: Flexible Nonstructural Components , 2006 .

[5]  Timothy J. Sullivan,et al.  Towards improved floor spectra estimates for seismic design , 2013 .

[6]  Pierino Lestuzzi,et al.  Seismic response of nonstructural components in case of nonlinear structures based on floor response spectra method , 2010 .

[7]  Francisco X. Flores,et al.  Assessment of floor accelerations in special steel moment frames , 2015 .

[8]  Samit Ray-Chaudhuri,et al.  Effect of Nonlinearity of Frame Buildings on Peak Horizontal Floor Acceleration , 2011 .

[9]  Timothy J. Sullivan,et al.  Estimating floor spectra in multiple degree of freedom systems , 2014 .

[10]  Peter Fajfar,et al.  A Nonlinear Analysis Method for Performance-Based Seismic Design , 2000 .

[11]  Mahesh D. Pandey,et al.  Generate floor response spectra: Part 1. Direct spectra-to-spectra method , 2015 .

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

[13]  Peter Fajfar,et al.  A method for the direct determination of approximate floor response spectra for SDOF inelastic structures , 2015, Bulletin of Earthquake Engineering.

[14]  Peter Fajfar,et al.  Consistent inelastic design spectra: Strength and displacement , 1994 .

[15]  Peter Fajfar,et al.  The extended N2 method considering higher mode effects in both plan and elevation , 2012, Bulletin of Earthquake Engineering.

[16]  Ricardo A. Medina,et al.  Floor response spectra for light components mounted on regular moment-resisting frame structures , 2006 .

[17]  Arash E. Zaghi,et al.  Floor Accelerations in Yielding Special Moment Resisting Frame Structures , 2013 .

[18]  Armen Der Kiureghian,et al.  Response spectrum analysis for floor acceleration , 2015 .

[19]  Anil K. Chopra,et al.  Evaluation of a Modified MPA Procedure Assuming Higher Modes as Elastic to Estimate Seismic Demands , 2004 .

[20]  Eduardo Miranda,et al.  Approximate Floor Acceleration Demands in Multistory Buildings. I: Formulation , 2005 .

[21]  R. Villaverde.  Simple method to estimate the seismic nonlinear response of nonstructural components in buildings , 2006 .

[22]  Dimitrios Vamvatsikos,et al.  A MODIFIED RESPONSE SPECTRUM METHOD FOR ESTIMATING PEAK FLOOR ACCELERATION DEMANDS IN ELASTIC REGULAR FRAME STRUCTURES , 2013 .

[23]  Mahendra P. Singh,et al.  Seismic Design Forces. I: Rigid Nonstructural Components , 2006 .

[24]  Murat Saatcioglu,et al.  Floor response spectra for seismic design of operational and functional components of concrete buildings in Canada , 2010 .