Dimensional Response Analysis of Multistory Regular Steel MRF Subjected to Pulselike Earthquake Ground Motions

Abstract

An alternative and efficient procedure to estimate the maximum inelastic roof displacement and the maximum inelastic interstorey drift ratio along the height of regular multi-storey steel MRF subjected to pulse-like ground motions is proposed. The method and the normalized response quantities emerge from formal dimensional analysis which makes use of the distinct time scale and length scale that characterize the most energetic component of the ground shaking. Such time and length scales emerge naturally from the distinguishable pulses which dominate a wide class of strong earthquake records and can be formally extracted with validated mathematical models published in literature. The proposed method is liberated from the maximum displacement of the elastic single-degree-of-freedom structure since the self similar master curve which results from dimensional analysis involves solely the shear strength and yield roof displacement of the inelastic multi-degree-of-freedom system in association with the duration and acceleration amplitude of the dominant pulse. The estimated inelastic response quantities are in superior agreement with the results from nonlinear time history analysis than any inelastic response estimation published previously.

Estimation of peak displacements in steel structures through dimensional analysis and the efficiency of alternative ground-motion time and length scales

“…(i) the Overall Normalized Error, E, estimated as [24]: 19) where N is the number of responses analysed, Π j u is the calculated displacement and Π j u is the displacement resulting from the predictive master curve (Equations 9, 11 or 12 for bilinear, PR or CB systems, respectively), and (ii) the Interquiartile-Range (IQR) calculated as the difference between the upper and lower quartiles of the error distribution which is a measure of statistical dispersion of the difference between calculated and estimated values of peak displacement.…”

“…It was shown that for given values of dimensionless yield displacement the maximum relative dimensionless deformations become self-similar and follow a single master curve. The concept of self-similarity was latter applied by Makris et al [24] and Karavasilis et al [19] to the estimation of inelastic demands in first-mode dominated structures behaving as elastoplastic systems and multi-storey regular Moment Resisting Frames (MRF) under various pulse-type excitations. The method rests upon the existence of characteristic length and time scales that mark the main energetic component of the earthquake excitation.…”

Collapse risk and residual drift performance of steel buildings using post-tensioned MRFs and viscous dampers in near-fault regions

“…Starting from the pioneer studies of Veletsos and Newmark (1960) and Bertero et al (1978), the response of yielding single-degree-of-freedom systems subjected to near-fault earthquake ground motions has been extensively studied (Chopra and Chintanapakdee 2003;Mavroeidis et al 2004 and references therein). Other studies focused on yielding frames and showed the potential of near-fault ground motions to induce large story drifts (Alavi and Krawinkler 2004;Makris and Psychogios 2006;Karavasilis et al 2010 and references therein).…”

The Dynamics of the Rocking Frame

“…It is emphasized that the persistence of the pulse, a p T p 2 = L p , is a different characteristic than the strength of the pulse which is measured with the peak pulse acceleration, a p . The reader may recall that among two pulses with different acceleration amplitudes (say a p1 > a p2 ) and different pulse durations (say T p1 < T p2 ) the inelastic deformation does not scale with the peak pulse acceleration (most intense pulse) but with the strongest length scale (larger a p T p 2 = most persistent pulse), [17,27,28]. The heavy dark line in Fig.…”