WIT Press


On The Dynamic Response Of Hardening Systems

Price

Free (open access)

Paper DOI

10.2495/ERES090201

Volume

104

Pages

11

Page Range

217 - 227

Published

2009

Size

538 kb

Author(s)

O. Sircovich Saar

Abstract

This paper relates to hardening systems, their response to dynamic forces and their contribution to seismic isolation of buildings’ foundations. The free vibration curve for a structure of continuous gradual changing of period and frequency, the dynamic load factor (DLF) for a suddenly applied constant load, and the curve of resonance for a pulsating sinusoidal force, are analyzed from the perspective of a structural engineer, which is essentially different from that of a researcher. The paper suggests a new approach for base seismic isolation, which is a combination of a base isolation device and a hardening steel structure. While the contribution of the isolation device is its characteristically high flexibility, the contribution of the steel structure consists of a smooth reduction of the building’s base displacement under a given earthquake. The combined isolation system also provides a gradual limitation of the building’s base displacement under an unexpected increase of the earthquake’s peak ground acceleration (PGA). Keywords: seismic isolation device, hardening steel structure, smooth reduction of base displacement, limitation of base displacement. 1 Introduction This paper presents a new approach for base seismic isolation, which is a combination of a base isolation device and a hardening steel structure. According to the results of preliminary investigations, this combination is conducive to a remarkable reduction of the maximum displacement of the isolated structure and to an appreciable limitation of this displacement under and unexpected increase of the design earthquake’s PGA. The response of a linear elastic structure, (curve 1 in fig. 1), subjected to a dynamic load is very well known and its basic characteristics, such as natural

Keywords

seismic isolation device, hardening steel structure, smooth reduction of base displacement, limitation of base displacement.