Investigation of Forward Directivity on Seismic Behavior of Low-rise Reinforced

Document Type : Research Paper

Authors

1 Ph.D. of Structural Engineering, Civil Engineering, KhatamolAnbia Resercher

2 Msc Structure, Civil Engineering, Alaodoleh Semnani Institute of Higher Education

Abstract

The characteristics of earthquakes vary both in terms of amplitude and frequency of content for sites at distances close to the seismic spring and far from it. However, the 2800 standard, which is used as the basis for the seismic design of the country, does not exclude the effects of the near-fault field on loading, and therefore the necessity of studying and comparing such effects on the response of structures is very necessary. Studies on the behavior of structures under the influence of near-field earthquakes have shown that the tracing of these types of earthquakes has more effects on structures (including permanent displacement and directional effects) than accelerations far from faults. Therefore, in order to estimate the near-active faults of earthquakes, the features of the near-earthquakes should be considered in the analysis and design of structures. Accordingly, in this research, we tried to study the effect of directional earthquakes near the seismic response of short concrete structure using time histories analysis. For this purpose, firstly, the records of the various stations of the quake were determined as the basis for the selection of accelerometers, and then using the analytical methods, the response spectrum of this acceleration, taking into account the directional effect and without it, as well as the pulse isolated from these records In two directions north-south and east-west. Then, according to the time history analysis on two short concrete structures with the number of stories 10, for 7 station records of the Taiwan Chichi earthquake, the drainage (relative displacement) of floors in structure was investigated. The results of this study showed that, due to the unpredictable nature of the earthquake, in short structure, in many cases, the availability of earthquake records has little effect on the response of the structures of the structures, and in some cases, it has reduced the structure response.

Keywords

References

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New Approaches in Civil Engineering
Volume 6, Issue 1
June 2022
Pages 53-64

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