SOIL PROFILE IDENTIFICATION AROUND NECATIBEY SUBWAY STATION (ANKARA, TURKEY), USING ELECTRICAL RESISTIVITY IMAGING (ERI)

Abstract

In this study, multi electrode resistivity method was applied in order to identify soil profile around Necatibey Subway Station of Kızılay-Çayyolu metro line, Ankara, Turkey. The Necatibey Metro Station is located within the alluvial deposits of Dikmen stream and the so-called Ankara clay. At the metro station a number of boreholes were drilled. However, due to the spacing of the boreholes the boundary between alluvium and Ankara clay deposits could not be separated precisely. Thus, electrical resistivity studies have been planned for the delineation of the boundaries of the two deposits. For every measurement section, Schlumberger N6-Dipole Dipole N4, Dipole Dipole N6, Schlumberger N6 and Wenner Alpha arrays were used. Measured data were interpreted by using RES2DINV software and correlated with borehole logs. According to resistivity sections taken from the location of Necatibey Station, silty clay and gravelly sand units which belong to Dikmen stream channel deposits, as well as fill material overlying and clayey levels which belong to Ankara clay underlying these units were identified. Based on borehole logs and resistivity data 3-dimensional lithological subsurface model of the survey area is constructed. The resultant 3dimensional diagrams may serve engineers as a practical tool while considering construction stages, groundwater-structure interactions within short and long term, and probable remedial measures

Keywords

• multi-electrode resistivity profile
• two-dimensional resistivity survey
• 3-dimensional subsurface model
• Necatibey subway station

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