Equivalent period and damping for EC8 spectral response of SDOF ring-spring hysteretic systemsFunded under: FP7-JRC
The following report presents a procedure to determine the equivalent properties of a viscoelastic linear model capable of approximating the maximum earthquake response of a SDOF ring-spring hysteretic system, representative of the cyclic behaviour of lightly reinforced concrete bridge piers, for a series of synthetic ground motions compatible with Type 1 and Type 2 Eurocode 8 spectra. The results show that the displacements obtained from the equivalent model approximate well the results obtained from the nonlinear model, and that the coefficients of the expressions for determining the equivalent properties depend on the family of earthquakes considered in the analysis. Expressions for determining the secant stiffness and equivalent damping corresponding to the energy dissipated by harmonic cycles at maximum displacement are derived for the ring-spring model and a relationship for computing a reduction factor of the maximum ductility is proposed such that the equivalent properties computed from these expressions approximate those obtained from the error minimization process. Recommendations to improve the error minimization process and the derivation of equivalent properties are proposed at the end of the report.
Bibliographic Reference: EUR 23365 EN (2008), 66 pp. Free of charge
Availability: http://bookshop.europa.eu/is-bin/INTERSHOP.enfinity/WFS/EU-Bookshop-Site/en_GB/-/EUR/ViewPublication-Start?PublicationKey=LBNA23365 (Catalogue Number: LB-NA-23365-EN-C)
Record Number: 200910057 / Last updated on: 2008-11-20
Original language: en
Available languages: en