Determination of Civil Engineering Problems Using Resistivity Methods in Ramadi, Western Iraq

Abstract

Many civil engineering problems resulting from the presence of gypsum soil near the surface and the water table in shallow depth led to the solubility of the soil and creates a subsurface weak area in Ramadi city. 2D and 3D electrical resistivity imaging were applied using a Dipole-dipole array with an n-factor of 6 and a-spacing values of 2 m. Imaging data sets have been acquired along five traverses with a line distance of 4 meters. The inversion model is generated by the robust inversion model constraint method, which clearly shows that the boundary of the weak area is sharper and straighter. The results show the presence of two main zones, the first represents the topsoil layer which extends to a depth of 2.5 m with a resistivity ranging from 28 to 312 Ωm. The second zone is located at 2.5 m depth and extends to 10 m with a resistivity value ranging from 0.267 to 28 Ωm. The variation of the water table, inhomogeneity of the sediment, weak areas, and sedimentation lenses are the main reasons for the failure of civil engineering. These failures may cause many problems such as wall cracks, foundation damage, and building collapses.