An Integrated geophysical approach for geotechnical site evaluation: A case study from new administrative capital, Egypt

The Egyptian government frequently pursues construction projects in East Cairo in accordance with the sustainable development plan in an effort to address the city's high population density. The study area is the New Administrative Capital, situated 45 kilometers to the east of Cairo, representing one of the most interesting new regions in Egypt. The primary goal of the current investigation is to ascertain the subsurface stratigraphy of the area, which is important for civil engineering applications such as building, by identifying the structural elements that break up the layers' continuity. 2D electric resistivity profiling (ERT) and shallow seismic refraction (SSR) surveys have been used to achieve the study's goal. Shallow seismic refraction measurements were carried out to identify the underlying ground model beneath the study area. Eleven Pwave profiles from carefully chosen locations around the area make up this seismic survey. Seismic data interpretation shows that the area's upper layer has a velocity range of 600–1000 m/sec, and the lower layer has a velocity range of 1000–4300 m/sec. 2D resistivity imaging measurements with a grid-mounted dipole-dipole electrode array. In order to investigate the nature of bedrock foundations, eleven 2D resistivity profiles were conducted at the same location as shallow seismic refraction profiles. According to the integration results, the subsurface section comprises four units: surface layer (sand, gravel, and rock fragments), sandstone, shale, and fractured limestone. There are highly fractured zones in the fractured limestone layer and clays in some places in the study zone, which could cause geotechnical problems. The study area's western region should see the majority of future expansion.