Paper Details

[ Downloads: 0 | Abstract Viewed: 116 | Pages: 9 ]

Abstract of the Article

Note: English CIVILICA is in its Trial Period so Full Texts can not be provided! Persian users can download it here

Seismic Hazard Analysis and Deaggregation Case Study: Abbas-Abad hills (north of Tehran)

Authors:
[ Mohammad Reza Ghayamghamian ] - Assistance Professor, International Institute of Earthquake Engineering and Seismology (IIEES)
[ Abdollah Sohrabi-Bidar ] - PHD Student of Seismology, Institute of Earthquake Engineering and Seismology (IIEES)

Abstract:

Tehran is located in southern part of Alborz mountains in the area with a high seismic activity and density of active faults. Hence, seismic hazards need to be realistically estimated for design of structures, especially for design of critical facilities. In engineering practice, the deterministic and probabilistic seismic hazard approaches are utilized to estimate the ground motion hazards (e.g. PGA) in specified return periods at a site. However, results of hazard calculation provide no information regarding what type of earthquakes actually produce these PGA values at a site or whether it should be a moderate event at short range or a large event at long range. In this study, we performed probabilistic seismic hazard calculations for the Abbas-Abad hills in north of Tehran using deaggregation technique. Deaggregating the hazard results reveal the contributions of different magnitude-distance pairs to the exceedance of probabilistic ground motion. It is a useful approach to define design earthquake(s) for the dominant contributor(s). Furthermore, its results serve as a guide for the selection of appropriate acceleration time histories or response spectra, particularly those involved in the dynamic analysis. Deaggregation results show that the ground motion hazard is dominated by earthquake near to M=7.0 (both return periods of 475 and 950 years) and at distance less than 30 km. The source of these earthquakes might be the North-Tehran, Mosha and Ray faults.

Keywords:

Tehran, Hazard Analysis, Probabilistic Approach, Seismic Hazard Deaggregation, North-Tehran Fault.