SEISMIC RELIABILITY-ANALYSIS OF REINFORCED-CONCRETE STRUCTURES WITH STOCHASTIC PROPERTIES

The paper investigates the potentialities of the method of equivalent stochastic linearization (ESL) as a tool for reliability analyses of n onlinear hysteretic structures with random mechanical properties, in v iew of its possible use for the probabilistic calibration of the safet y elements used in seismic design. In particular, behavior factor a an d capacity design (CD) factors are investigated. For this purpose, the method is extended in the paper to cover the case of a response proce ss with a non-zero mean, a situation occurring even for a zero mean in put due to the combined presence of the seismic loads with the gravita tional ones, which in turn leads to unsymmetrical force-deformation la ws at both local and global level. To show the practicality of the met hod, two problems for which code provisions are still largely judgment al have been considered with a few examples: the quantification of the q values for structures with setbacks, and of the CD factors for stru ctures with relatively large vertical loads. The results allow some co nsiderations of practical interest to be drawn, while confirming the E SL: as an appropriate and economical tool for a systematic support of seismic codes. Copyright (C) 1996 Elsevier Science Ltd.