Muhammad Yanis
Geophysical and geotechnical approaches in developing subsurface model for gas power plant foundation - Vol.52(1), Feb - USA Springer 2022 - 237-247p.
A study of a foundation depth has been carried out using the geophysical method to construct a gas engine power plant, operating at 130 MW in Ladong, Aceh Province. Vertical electrical sounding (VES) is a geophysical technique that uses direct current to determine subsurface resistivity. The method was employed at three stations for subsurface soil resistivity analysis by utilizing the Schlumberger configuration. This study examines the geoelectric parameters used to evaluate the stratigraphy, structural integrity, and competence of shallow subsurface, which are helpful for building and other construction as a good engineering practice. The inversion result from VES data shows five resistivity layers up to 100 m in the subsurface, i.e. topsoil, clay to sand breccia, blocky andesite, and the last layer is blocky andesite contain groundwater. Three VES station results show the depth of the building foundation efficiently and economically is 7–17 m, dominated by blocky andesite and massif andesite having a resistivity of 13–31 Ωm. While at a depth of below 10 m, the resistivity also validated to geotechnical data acquired in the same site, at a depth of above 6 m, the borehole data have also shown a similar lithology to VES by having fine sand loam mixed with small rocks and gravel (pyroclastic deposit) characterized by texture from fine to coarse package very dense, stiff, and slightly cohesive. Moreover, it could be derived that the topsoil layer with a thickness of fewer than 1 m is classified as a corrosive zone, and a layer in the depth interval of 1– < 7 m is categorized as a highly corrosive stratum. The results indicate that the VES method can effectively provide geotechnical investigation, such as soil foundation information.
Civil Engineering
Geophysical and geotechnical approaches in developing subsurface model for gas power plant foundation - Vol.52(1), Feb - USA Springer 2022 - 237-247p.
A study of a foundation depth has been carried out using the geophysical method to construct a gas engine power plant, operating at 130 MW in Ladong, Aceh Province. Vertical electrical sounding (VES) is a geophysical technique that uses direct current to determine subsurface resistivity. The method was employed at three stations for subsurface soil resistivity analysis by utilizing the Schlumberger configuration. This study examines the geoelectric parameters used to evaluate the stratigraphy, structural integrity, and competence of shallow subsurface, which are helpful for building and other construction as a good engineering practice. The inversion result from VES data shows five resistivity layers up to 100 m in the subsurface, i.e. topsoil, clay to sand breccia, blocky andesite, and the last layer is blocky andesite contain groundwater. Three VES station results show the depth of the building foundation efficiently and economically is 7–17 m, dominated by blocky andesite and massif andesite having a resistivity of 13–31 Ωm. While at a depth of below 10 m, the resistivity also validated to geotechnical data acquired in the same site, at a depth of above 6 m, the borehole data have also shown a similar lithology to VES by having fine sand loam mixed with small rocks and gravel (pyroclastic deposit) characterized by texture from fine to coarse package very dense, stiff, and slightly cohesive. Moreover, it could be derived that the topsoil layer with a thickness of fewer than 1 m is classified as a corrosive zone, and a layer in the depth interval of 1– < 7 m is categorized as a highly corrosive stratum. The results indicate that the VES method can effectively provide geotechnical investigation, such as soil foundation information.
Civil Engineering