An Alternative Seismic Hazard Definition for Structures Sensitive To Bi-Directional Earthquake Excitation

Abstract eng:
Although earthquake ground motions are complex three-dimensional phenomena, the seismic design of a structure is usually carried out considering horizontal ground shaking in two perpendicular directions only. While the issue of ground motion dependence on the orientation of the recording devices has been the focus of many significant developments during the last decade, the effects of directionality on the characteristics of the structure has received less attention. This paper uses three case-study structural typologies and a set of 405 ground motion pairs from the Reference Database for Seismic Ground-Motion in Europe (RESORCE) to demonstrate the relevance of accounting for directionality in the design and assessment of structures. An alternative definition of hazard that breaks down the problem into an orientation-independent and an orientation-dependent component is proposed with the aim of achieving uniformity in the likelihood of different types of buildings exceeding a certain limit state. The challenges associated with the incorporation of this new perspective to seismic codes within the context of Performance-Based Earthquake Engineering are discussed. Though the focus of this work is set on elastic response of single-degree-of-freedom (SDOF) systems, the approach presented herein is considered to be a fundamental initial step towards a design philosophy that guarantees that the seismic performance of a building does not depend on its sensitivity to the angle of incidence of ground motions.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket