Mapping of buried utilities and electrical line in order to avoid the occurrence of accidents and damages during the execution drilling research. Since the investigated land was located in an industrial site, the presence of numerous metalic elements made it impossible to use electromagnetic equipment in time domain and vertical magnetic gradient method. Georadar (GPR) method was also impossible to use because of the land deformation, boulders layer and gravel surface; all these prevent coherent and interpretable signal reception. Under these condition we used only electromagnetic induction locator with different frequencies signal. The result were very good and penetration of passive and active cables or pipelines were avoided.
Geophysical investigation through vertical magnetic gradient for highlighting and positioning burried metal objects. Since the land presented many anomalies we used electromagnetic locator with passive and active signal. In these condition has been identified electrical line that crossed the perimeter and buried concret blocks. For land with high electromagnetic noise, the results of many buried metal objects, we rezommend several complementary geophysical methods to disseminate geophysical signal. Profile positioning was performed with high precision RTK GPS.
Electromagnetic measurements for highlighting buried metal objects – utilities, UXO, unknown objects – in order to avoid possible accidents during engineering works. For investigating a perimeter of 16 ha, an EM61MK2 was used, a highly effective tool for such explorations and a RTK GPS with high precision for determining the exact measurement paths. The result of these investigations emphasized the areas with a high potential of risk for performing excavation or drilling research.
Geoelectrical investigations, namely electrical tomography, in order to determine the local geological and hydrogeological conditions which favored a landslide on the national road DN6B, Stoina-Hurezani. Investigations have revealed a possible slip plane and the particular geological conditions of the area. These investigations helped draft the design of future geotechnical drillings and works for land stabilization.
Sections of electrical tomography in order to characterize the local geological conditions in the area of development of a wind farm. For establishing the exact geological conditions, geoelectrical cross sections were designed and executed, centered on the axis of wind towers. The result helped design the geotechnical drillings and the foundations for future wind towers.
Geophysical research through electrical tomography method for highlighting a channel for rainwater collection situated under a future highway. For this research three measuring devices were used – Schlumberger, Wenner and dipole-dipole. The results are very convincing and confirm the effectiveness of using geoelectrical devices for identifying underground utilities and the specific geological characteristics of the investigated site.
Geoelectrical tomography for identifying local geological and hydrogeological conditions that favored the occurrence of landslides that endanger stability of future works developed in the research area. Geoelectrical sections helped to identify the characteristics of sliding plan and establish measures to stabilize the land. The work involved exploring through cross and longitudinal sections of a line of over 8 km of highway with high traffic areas. In these circumstances it was necessary to execute certain profiles at night to avoid disrupting works in progress and traffic.
Geoelectrical investigations to identify and characterize local geological conditions found in the area of undercrossing the Danube through horizontal directional drillings. The geoelectrical measurements were performed on water using cables and devices specially designed for this kind of work. Taking into account the Danube’s characteristics in the research area – width of 500 m, flow speed, intense sailing – the geoelectrical measurements were performed in Vertical Electrical Sounding (VES) method using two boats. Locating the exact position of VES was performed with a RTK GPS with high precision and water depth was measured using an Ohmex sonar. The results of these investigations have resulted in an interpretive geological section necessary for designing the future horizontal directional drillings.
Bathymetric measurements for drawing a bathymetric map of a Danube sector between Comasca (Romania) and Marten (Bulgaria). As required, measurements were made on alignments predefined by using Ohmex equipment and GPS GNSS. The compensation of topographic data was done with connection to the network ROMPOS.
Measurements of the variation of vertical magnetic gradient in order to identify metal objects hidden (buried or submerged) on the alignment of the horizontal directional drilling that undercrosses the Danube between Romania and Bulgaria. For the absolute positioning of measurements, a GPS Stonex GNSS equipment with high precision was used. The measuring equipment was magnetically isolated from the rest of the boat so that there would be no influence caused by boat.