Document Type : Original Research Paper

Authors

1 M.Sc. Student, Department of Geology, Islamic Azad Univeristy, Sciences and Research Branch,Tehran, Iran

2 Assistant Professor, Research Institute for Earth Sciences, Geological Survey of Iran, Tehran, Iran

3 Associate Professor, Department of Geology, Islamic Azad Univeristy, Sciences and Research Branch, Tehran, Iran

4 4 Professor, Faculty of Civil Engineering, Sharif University of Technology, Tehran, Iran

Abstract

Earthquake is an undeniable phenomenon that can cause financial and social damage if occur in populated areas.  Vulnerability of buildings is not just function of magnitude and distance from the epicenter but also depends on physical properties of soil. In this study we evaluate physical properties of alluvium in an area of approximately 100 square kilometers in west of Tehran between longitudes 51 º 15´ to 51º 23´ and latitudes 35º 40´ to 35º 50´. As a first step we collected field data regarding the alluvium deposits as well as location of Quaternary faults. We then combined this information with data from 440 boreholes which were aquired from more than hundred urban development projects. We use sedimentological diagrams of the boreholes to define three zones of coarse-, intermediate- and fine-grained material in the region. We considered physical and mechanical properties of the sediments to produce seismic amplification map of the area which shows three zones of high, moderate and no amplification. Finally, we investigated liquefaction potential of sediments, considering ground water level and structure of the basin and we have concluded that there is no potential of liquefaction in the area of study.

Keywords