Report - PEER - University of California, Berkeley

(M8 and M9) and the isolated frames (M10 through M15). Importantly, the spectralpeaks of the moment-frame structures (M3 and M6) are suppressed through theaddition of viscous damping: an observation reported first by Pavlou andConstantinou (2004).Spectral acceleration (g)642010 −1 10 0 10 1 10 2Frequency (Hz)Spectral acceleration (g)8642010 −1 10 0 10 1 10 2Frequency (Hz)a. 2nd floor (A2) b. 4th floor (A4)M3M6M7M8M9M10M11M12M13M14M15Spectral acceleration (g)642010 −1 10 0 10 1 10 2Frequency (Hz)c. normalized 4 th floor (A4)Figure 9. Floor acceleration spectra for 10/50 earthquake histories.Normalized 5-percent damped 4th floor acceleration spectra are presented inFigure 9c for the 5 non-isolated buildings (M3, M6, M7, M8 and M9). The figureshows the amplification of the peak floor acceleration as a function of structuralframing system. For the same peak floor acceleration, the performance of the viscousdamped buildings, M8 and M9, is clearly superior to the traditional moment-framebuildings and the building equipped with BRBs.4. CLOSING REMARKSThe next generation tools for PBEE will recognize the substantial financialinvestment in nonstructural components and contents (Figure 1). Significant researchwork is underway at the three NSF-funded earthquake research centers to developperformance assessment tools for NCCs (Whittaker and Soong, 2003).To reduce losses in buildings in future earthquakes, the current performancebaseddesign paradigm must be updated to shift the focus to NCCs. The geometry,type and materials that comprise a structural framing system should be selected by the123