Geoelectric survey for reactivation planning from Madiun-Slahung railway track in Indonesia

Reactivation of the Madiun - Slahung railway track up grade in the medium speed category, it is necessary to know the subsurface lithology. Safety was analyzed from the measured lithology slices. Measurement of the soil reactivation path using the wenner-schlumberger configuration 2d geoelectric resistivity method. Land identification using topographic maps, land use maps, road network maps and geological maps. Data collection is based on the acquisition design in the villages of Slahung, Broto, and Menggare with a track length of 195 m and an electrode spacing of 5 m. RhoApp calculation and bad datum analysis are performed for data processing to reduce data except the trend that causes high errors. The 2D cross-sectional output of parameter inversion results can display apparent resistivity (ρ). UDS testing is in the form of triaxial UU test, volumetry, and gravimetry on soil samples taken from a depth of 0.5-1 m. Undisturbed soil sample was used to determine the measurement parameters. The result is a subsurface lithology consisting of top soil with a resistivity of 14 to 210 ωm, Clay with a resistivity of 4 to 30 ωm, and sand with a resistivity of 19 to 204 ωm. While the carrying capacity of the soil with a permit stress value of 30.6474 t / m2.