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Lateral-Torsional Response of Structures Subjected to Seismic Waves.
Wu, S. T.; Leyendecker, E. V.
June 1983, 30 p.
Identifying Number(s)
The behavior of coupled lateral-torsional systems subjected to seismic waves is investigated analytically. The report presents the numerical results of a parametric study for structures subjected to S-H waves. Case studies are provided to show the contribution of each of the selected parameters to the rotational response of the systems. These parameters are: geometric eccentricity, aspect-ratio of the foundation mat, damping ratio, and the ratio of the rotational to translational frequencies. Dynamic eccentricity is selected as an index to represent the level of the response. The sensativity due to the deviation of the input spectrum is investigated. Accidental eccentricities due to seismic waves are also evaluated. Design concerns are given on how the design eccentricity should be considered based on this study.
Seismic design; Earthquake resistant structures; Rotation; Seismic waves; Eccentricity; Structural design; Dynamic response; Earthquake engineering