This paper applies recent research on structural damage description to earthquake-resistant design concepts. Based on the primary\r\ndesign aim of life safety, this work adopts the necessity of additional protection aims for property, installation, and equipment.\r\nThis requires the definition of damage indicators, which are able to quantify the arising structural damage. As in present design,\r\nit applies nonlinear quasistatic (pushover) concepts due to code provisions as simplified dynamic design tools. Substituting so\r\nnonlinear time-history analyses, seismic low-cycle fatigue of RC structures is approximated in similar manner.The treatment will\r\nbe embedded into a finite element environment, and the tangential stiffness matrix K?? in tangential subspaces then is identified as\r\nthe most general entry for structural damage information. Its spectra of eigenvalues ???? or natural frequencies ???? of the structure\r\nserve to derive damage indicators ????, applicable to quasistatic evaluation of seismic damage. Because det K?? = 0denotes structural\r\nfailure, such damage indicators range from virgin situation ???? = 0 to failure ???? = 1 and thus correspond with Fema proposals on\r\nperformance-based seismic design. Finally, the developed concept is checked by reanalyses of two experimentally investigated RC\r\nframes.
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