The Earthquake Engineering Online Archive

Advanced seismic assessment guidelines

Bazzurro, Paolo; Cornell, C. Allin; Menun, Charles A.; Motahari, Maziar; Luco, Nicolas

PEER-2006/05, Pacific Earthquake Engineering Research Center, University of California, Berkeley, 2006, pdf (400/P33/2006-05)

This document presents guidelines for a practical assessment of the seismic performance of existing structures. Performance is measured in terms of the likelihood that a building, given a level of ground motion, can be in any one of five structural limit states after an earthquake: onset-of-damage, green tag, yellow tag, red tag, and collapse. The green-, yellow-, and red-tag states are directly related to structural post-earthquake functionality. The link between the patterns of structural damage that could be observed after a mainshock and the assignment of the appropriate limit state to each damage pattern is made using loss of capacity as the quantitative measure of performance degradation. The objective criterion used by the procedure to assign the appropriate tagging condition to a given damage pattern is the likelihood that an aftershock ground motion will exceed the specific (reduced) capacity. The loss of capacity for each damage pattern induced by a mainshock is evaluated using state-of-practice engineering analyses performed before an earthquake. The results of these guidelines are twofold. First and foremost, after appropriate consideration of uncertainty in building response and capacity, the guidelines provide a rational procedure for developing fragility curves for green, yellow, and red tags, and for collapse of an intact building. Secondly, this procedure provides the engineer inspecting the facility after an earthquake a rational criterion for deciding whether and when to permit re-occupancy.

Available online: http://peer.berkeley.edu/publications/peer_reports/reports_2006/web_PEER605_BAZZURRO_etal.pdf