(Wydawnictwa AGH, 2026) Cichostępski, Kamil; Bania, Grzegorz; Borecka, Aleksandra
The paper presents an integrated use of multichannel analysis of surface waves (MASW) and electrical resistivity tomography (ERT) to characterise the physical properties of near-surface materials, identify subsurface structures, and estimate the depth to bedrock in a planned construction area near Czernichów, close to Krakow (southern Poland). The study shows that integrating MASW and ERT provides a cost-effective and complementary approach to subsurface characterisation, delivering more reliable and less ambiguous interpretations than when the methods are applied independently, thereby reducing the need for expensive and invasive in situ geotechnical investigations. Particular emphasis is also placed on the methodological aspects of both methods. The study site is located on an alluvial plain composed of alluvial soils, sands, sand–gravel mixtures, and silty clays overlying limestone bedrock. Geophysical data were collected along five profiles. The resulting shear wave velocity models and the inverse model resistivity sections show good agreement with borehole data. The study area is characterised by a wide range of physical parameters derived from both methods. The MASW survey enabled recognition of the subsurface down to the bedrock, revealing four seismic layers differing in S-wave velocity. Nevertheless, the MASW inversion did not provide reliable estimates of the limestone S-wave velocity, although it successfully delineated its depth and morphology. The ERT survey identified three geoelectrical layers and proved to be more effective in resolving shallow geological structure, particularly in identifying the boundaries between alluvial soils and sand–gravel mixtures, whereas the depth and morphology of the limestone bedrock were constrained primarily by MASW.
Accurate detection and mapping of underground utilities in complex urban environments, particularly in intensive construction zones such as tunnel sites, presents a significant engineering challenge. This paper investigates the application of ground penetrating radar (GPR) integrated with high-accuracy real-time kinematic (RTK) GNSS positioning to identify and spatially define a damaged sewer pipeline above the Kobilja Glava tunnel construction site in Sarajevo, Bosnia and Herzegovina. Non-destructive investigation was required due to the lack of reliable underground utility documentation and wastewater ingress into the tunnel during construction. The study was conducted under complex urban and geotechnical conditions, including asphalt pavement, high soil moisture, heterogeneous subsurface layers, and proximity to the tunnel. GPR surveys were performed using a dual- channel Leica DS2000 system with 250 MHz and 700 MHz antennas, combining grid-based and free-profile measurements. Spatial georeferencing was achieved with a Topcon Hiper HR RTK GNSS receiver, which provides centimeter-level positioning of identified reflectors within the national coordinate system of Bosnia and Herzegovina. Data processing and interpretation followed standard GPR procedures. Results show that the sewer pipeline was reliably identified through hyperbolic reflections, with the depth of the pipe crown ranging from 1.1 to 1.7 m. Integration of GPR and GNSS data enabled precise reconstruction of the pipeline’s position and depth, supporting the design of a new pipeline and reducing construction risks. The study demonstrates the high effectiveness of the integrated GPR-GNSS approach in complex urban environments near tunnel structures. These findings suggest that the integration of GPR and GNSS technologies serves not only for object detection but also provides a critical methodological framework for real-time risk assessment during underground construction. The study demonstrates how precise spatial definition of damaged infrastructure can prevent broader geotechnical instabilities, elevating the work from a local case study to a universal model for monitoring urban infrastructure under stress.
A geophysical survey using electrical imaging in the Wenner–Schlumberger configuration was carried out in a crystalline basement region in central Côte d’Ivoire to improve knowledge of the aquifers in this area affected by recurrent water stress. The 2D resistivity sections, corroborated by petrographic field observations and drilling data, led to the development a 3D conceptual model of the aquifers in the study area. This model distinguishes three main lithological units: a resistant surface cover consisting of a lateritic cuirass, a conductive alteritic layer, and, at the base, a more or less fractured crystalline basement. From a structural point of view, several fracture networks have been identified, with predominantly NW–SE, NNW–SSE, and N–S orientations, constituting potential groundwater circulation zones.
(Wydawnictwa AGH, 2026) Gondek, Krzysztof; Baran, Agnieszka; Siudek, Michał
There is an ongoing search for the most environmentally friendly use of various materials as additives to improve sludge properties. The aim of this study was to analyze the effect of additive type and dose of biochar (BC), dolomite (DL), bentonite (BN) or diatomite (DT) on heavy metal immobilization, organic matter stability, biochemical activity and ecotoxicity of municipal sewage sludge (SS). Risk Assessment Code (RAC) and Ecological Risk Factor (ERF) values indicated low risk associated with heavy metal (HM) mobility. Higher non-hydrolyzing C contents, compared to SS control, were found in SS to which 1% BC (by 3.6%), 1% DL (by 38.0%), 1% BN (by 25.5%) and 1% DT (by 20.6%) were added. Higher ratio C humic acids/C fulvic acids (Ckh/Ckf) values (more than 30% on average) were obtained when 1% BC, DL or BN were added compared to the 3% addition. Compared to the SS, the Ckh/Ckf values in SS with the addition of BC, DL or BN were on average more than 19% higher. The least varied values of dehydrogenase activity and respiration activity of SS (within dose) were obtained after the application of DT and BC, while the values of both parameters differed the most when BN was added to SS. Based on the results, it is not possible to clearly state which of the applied additives had the most significant effect on reducing the biochemical activity of SS. Sewage sludge and its mixtures generally showed low phytotoxicity to Sorghum saccharatum and Lepidium sativum, as root growth inhibition was 8–56% and 17–48%, respectively.
