000018982 001__ 18982
000018982 005__ 20170118182252.0
000018982 04107 $$aeng
000018982 046__ $$k2017-01-09
000018982 100__ $$aCruz, Ernesto
000018982 24500 $$aEstimation of Relative Displacements on Equipment Or Secondary Structures Under Severe Earthquake Excitation

000018982 24630 $$n16.$$pProceedings of the 16th World Conference on Earthquake Engineering
000018982 260__ $$b
000018982 506__ $$arestricted
000018982 520__ $$2eng$$aThe design of equipment or substructures mounted on industrial structures is commonly addressed from the perspective of the adequacy of the anchoring system. The results for the design of the supports and anchoring devices in terms of forces, accelerations, and displacements and also for the study of the behavior of the equipment are obtained from the same analysis carried out for the primary structure, which is usually a response spectrum analysis (RSA) that considers a response modification factor to take into account in a very approximate manner the energy dissipation behavior of the primary structure. The codes allow estimating the “expected displacement” of the structures through the amplification of the displacements obtained from the RSA (for reduced earthquake action) by a factor similar or equal to the response modification factor, based mainly on the “equal displacement rule”. However, the nonlinear behavior inherent to the equipment or substructure, if it exists, is completely independent from the nonlinear behavior of the primary structure. Furthermore, in many cases the configurations of the equipment or substructure are not comparable to the configurations of the primary structures and therefore the applicability of the provisions of the codes is at best uncertain. A parametric evaluation of the displacements of a range of secondary structures has been carried out using timehistory analysis considering different levels of nonlinear behavior in the primary structure while the secondary structure has been made to remain elastic. Average results over a set of 10 ground motions have been compared with the estimations obtained from the RSA results considering the average spectrum of the ground motions, for a range of period of the primary structure and a range of ratios between the secondary and the primary structures. The results from linear and nonlinear analyses are compared first in terms of the story shears and interstory drifts of the primary structure and also in terms of the drifts in the secondary structure. The primary structure results confirm the trends in the behavior already observed by many researchers, while the set of results for the secondary structure drifts show that using the same approach for the estimation of "inelastic" values is always a "safe side assumption" but in some cases can grossly overestimate the results.

000018982 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000018982 653__ $$aSecondary systems; Industrial structures; Expected seismic demand; Relative displacements

000018982 7112_ $$a16th World Conference on Earthquake Engineering$$cSantiago (CL)$$d2017-01-09 / 2017-01-13$$gWCEE16
000018982 720__ $$aCruz, Ernesto$$iFoneron, Rodrigo$$iValdivia, Dania
000018982 8560_ $$ffischerc@itam.cas.cz
000018982 8564_ $$s649471$$uhttps://invenio.itam.cas.cz/record/18982/files/2630.pdf$$yOriginal version of the author's contribution as presented on USB, paper 2630.
000018982 962__ $$r16048
000018982 980__ $$aPAPER