SUMMARYPerformance-based seismic design requires reliable methods to predict earthquake demands on structures, and particularly inelastic deformations, to ensure that speciÿc damage-based criteria are met. Several methods based on the response of equivalent linear single-degree-of-freedom (SDOF) systems have been proposed to estimate the response of multi-degree-of-freedom structures. These methods do not o er advantages over the traditional Veletsos-Newmark-Hall (VNH) procedure, indeed, they have been shown to be inaccurate. In this study, the VNH method is revised, considering the inelastic response of elastoplastic, bilinear, and sti ness-degrading systems with 5% damping subjected to two sets of earthquake ground motions. One is an ensemble of 51 earthquake records in the Circumpaciÿc Belt, and the other is a group of 44 records in California. A statistical analysis of the response data provides factors for constructing VNH inelastic spectra. Such factors show that the 'equal-displacement' and 'equal-energy' rules to relate elastic and inelastic responses are unconservative for high ductilities in the acceleration-and velocity-sensitive regions of the spectrum. It is also shown that, on average, the e ect of the type of force-deformation relationship of non-linear systems is not signiÿcant, and responses can be conservatively predicted using the simple elastoplastic model.

Las ciudades del cobre. Del campamento de montaña al hotel minero como variaciones de la company town **

No abstract

No abstract

No abstract