Seismic Hazard Assessment in Alluvial Areas West of Tehran

The purpose of this study was to determine the vulnerable and resistant areas of alluvial areas of west of Tehran against seismic hazards. The research method included the study of important fractures, effective faults, the use of sediment diagrams of drilled boreholes and geotechnical data. Samples were examined from two aspects of density and standard penetration test. Finally, an alluvial zoning map of the western regions of Tehran was prepared and plotted against seismic hazards. According to this study, the south-eastern part of the study area has the most impact in terms of intensification of seismic waves and its northern part does not have any intensification. In addition, due to the soil quality, the possibility of liquefaction in the study area is also important. Since the city of Tehran is based on alluvial formations, it is essential for designers and builders of civil engineering projects to examine the type and extent of alluviums and their response to seismic hazards in Tehran, as these data are used by planners to strengthen different urban areas and reduce seismic hazards. In this study, for the first time, the effect of seismic waves was evaluated based on the subsurface connections of faults with alluvial areas in the west of Tehran.