Mitigation of Higher Mode Effects in Base-Rocking Systems by Using Multiple Rocking Sections

Base-rocking systems have been proposed as a way to limit the seismic forces experienced by a structure without accepting structural damage. However, structural forces can increase significantly, even when the base moment is limited, because of higher mode effects. This article suggests that these effects may be substantially reduced by designing to allow rocking to occur at multiple locations over the height of a base-rocking system. This is confirmed by a statistical study of the response of 24 systems of varying height and joint configuration to two suites of 20 earthquakes, as well as by a case study of the response of five 12-story systems designed using a displacement-based procedure. The bending moment envelope above the base of the wall is shown to be greatly reduced by providing multiple rocking sections, while the peak displacements do not increase in magnitude or in variability.

[1]  S. Pessiki,et al.  Analytical and Experimental Lateral Load Behavior of Unbonded Posttensioned Precast Concrete Walls , 2007 .

[2]  Stephen Pessiki,et al.  Seismic behavior and design of unbonded post-tensioned precast concrete frames , 1999 .

[3]  John F. Stanton,et al.  An Overview of the PRESSS Five-Story Precast Test Building , 1999 .

[4]  A. Buchanan,et al.  Experimental investigations on LVL seismic resistant wall and frame subassemblies , 2006 .

[5]  Gian Michele Calvi,et al.  Seismic design of frame-wall structures , 2006 .

[6]  José I. Restrepo,et al.  Seismic performance of self-centering structural walls incorporating energy dissipators , 2007 .

[7]  STEFANO PAMPANIN,et al.  ANALYTICAL MODELLING OF THE SEISMIC BEHAVIOUR OF PRECAST CONCRETE FRAMES DESIGNED WITH DUCTILE CONNECTIONS , 2001 .

[8]  Mervyn J. Kowalsky,et al.  Displacement-based seismic design of structures , 2007 .

[9]  Andre Filiatrault,et al.  Seismic response of self‐centring hysteretic SDOF systems , 2002 .

[10]  John B. Mander,et al.  Seismic Performance of Precast Reinforced and Prestressed Concrete Walls , 2003 .

[11]  Yahya C. Kurama,et al.  Hybrid Post-Tensioned Precast Concrete Walls for Use in Seismic Regions , 2002 .

[12]  Cyclic Soil Plasticity.  EUROPEAN SCHOOL FOR ADVANCED STUDIES IN REDUCTION OF SEISMIC RISK ROSE SCHOOL , 2002 .

[13]  Yahya C. Kurama,et al.  Seismic Design of Partially Post-Tensioned Precast Concrete Walls , 2005 .

[14]  L. Wiebe,et al.  SEISMIC RESPONSE OF SELF-CENTERING BASE-ROCKING STEEL STRUCTURES , 2007 .

[15]  M. Priestley,et al.  Dynamic Amplification of Seismic Moments and Shear Forces in Cantilever Walls , 2003 .

[16]  N. Null.  Minimum Design Loads for Buildings and Other Structures , 2003 .

[17]  Richard Sause,et al.  DESIGN OF SELF-CENTERING STEEL CONCENTRICALLY-BRACED FRAMES , 2006 .

[18]  Constantin Christopoulos.  Frequency Response of Flag-Shaped Single Degree-of-Freedom Hysteretic Systems , 2004 .

[19]  Johnny Sun,et al.  Development of Ground Motion Time Histories for Phase 2 of the FEMA/SAC Steel Project , 1997 .

[20]  Gian Michele Calvi,et al.  Displacement‐Based Design of Precast Walls with Additional Dampers , 2009 .

[21]  Akira Wada,et al.  Shaking table tests on seismic response of steel braced frames with column uplift , 2006 .

[22]  Javeed A. Munshi.  DESIGN OF PRESTRESSED FLEXURAL SECTIONS BY THE UNIFIED DESIGN APPROACH , 1999 .

[23]  Andre Filiatrault,et al.  SEISMIC SHEAR DEMAND OF DUCTILE CANTILEVER WALLS - A CANADIAN CODE PERSPECTIVE , 1994 .

[24]  D. Young,et al.  Tables of characteristic functions representing normal modes of vibration of a beam , 1949 .

[25]  Alessandro Palermo,et al.  Dynamic Testing of Precast, Post-Tensioned Rocking Wall Systems with Alternative Dissipating Solutions , 2008 .

[26]  Alessandro Palermo,et al.  Design, Modeling, and Experimental Response of Seismic Resistant Bridge Piers with Posttensioned Dissipating Connections , 2007 .

[27]  Richard Sause,et al.  Ductility demands on self-centering systems under earthquake loading , 2005 .

[28]  Alessandro Palermo,et al.  Section Analysis and Cyclic Behavior of Post-Tensioned Jointed Ductile Connections for Multi-Story Timber Buildings , 2008 .

[29]  Sri Sritharan,et al.  Preliminary results and conclusions from the PRESSS five-story precast concrete test Building , 1999 .