Investments in made ground are a big problem. The present investigation concerns ground derived from limestone treatment waste from SOLVAY soda plants. This waste is deposited in the southern area of Krakow in a reservoir called ‘White Seas’ in an area of approximately 15 ha. Currently, part of the route and tram investment, ‘The Łagiewniki Route’ Currently through the ‘White Seas’ area. The article presents an analysis of a section of this route by a high and steep slope made from made ground. The first stage of the in-situ measurements was to scan the shape of the high slope with the RIEGL VZ-400 terrestrial laser scanner. It was necessary to obtain the shape of the slope for numerical modelling using the FEM method. The point cloud perfectly reflected the shape of the slope with an accuracy of 5 mm. Soil samples (limestone waste) were also collected in the area of the slope for laboratory tests. In order to determine the effective strength parameters of the made ground of the embankment, a series of tests was carried out using triaxial compression apparatus. All triaxial tests were performed in accordance with British Standard 1337 Part 8. Modelling was performed using an FEM finite element method in MIDAS. The analyses also included the variant of irrigation of made ground. The conducted research shows that the high and steep slope made from calcareous waste indicates stability. The irrigated land did not make the high escarpment unstable.

The poorly cemented Ciężkowice poorly sorted sandstone and the compact Mucharz fine grain sandstone have been laboratory tested at the triaxial compressing conditions in thermo-pressurized chamber of a rigid press MTS-815. The confining pressure: P = σ₂ = gσ₃ range from 0 to 96 MPa and the temperature: T from 22°C to 120°C (simulated 500 m intervals from the surface to the depth of 3500 m). During (the) each test, the characteristics of deformation and the elastic wave velocity paths were simultaneously monitored. The volume density and longitudinal wave velocity showed a non-linear increase with the progress of simulated depth, a volume density growth by 1.6 to 4.0%, and the elastic wave velocity up to 250% of the primary value (surface condition), dependable on loading path, phase of deformation, and varying type of lithology. That may lead to wide error margin in a determination of rock’s engineering properties and also create discrepancies between the static parameters of rocks (Est, gνst) determined by standard laboratory load tests, and the dynamic parameters (Ed, νd) determined from the wave velocity and volume density.

The ductility of High Performance Concrete (HPC) can develop both in tension and compression.This aspect is evidenced in the present paper by measuring the mechanical response of normalvibrated concrete (NC), self-compacting concrete (SC) and some HPCs cylindrical specimensunder uniaxial and triaxial compression. The post-peak behaviour of these specimens is definedby a non-dimensional function that relates the inelastic displacement and the relative stress duringsoftening. Both for NC and SC, the increase of the fracture toughness with the confinement stressis observed. Conversely, all the tested HPCs, even in absence of confinement, show practically thesame ductility measured in normal and self-compacting concretes with a confining pressure. Thus,the presence of HPC in compressed columns is itself sufficient to create a sort of active distributedconfinement.

Nowadays, geotechnical specialists are focused on reinforcing soil engineering parameters using innovative and environmentally friendly methods. Microbial-Induced Calcite Precipitation is a ground improvement method for modifying soil strength, permeability, and stiffness; therefore, it can be vital to study the effective factors on the technique’s efficiency and cost reduction. This study examined how biologically treated sands subjected to undrained triaxial loading responded to simultaneous changes in cementation solution molarity, optical density (OD600), and curing time. The triaxial experiments showed that the strength increased with the rise in the mentioned parameters. While the solution molarity and optical density had the highest and lowest effect on the soil improvement process, respectively, the optical density role was considerably low when the molarity was high. Increasing the molarity of the cementation solution resulted in a 45% increase in the peak stress ratio, while the optical density and curing time were constant. On the other hand, similar behaviour of dense sand and change in the response of cemented soil from strain-hardening to strain-softening were other notable observations of this study. In addition, the peak stress ratio at low strains increased with increasing the cementation level and then decreased to close to the amount of untreated sand with increasing strain.

The paper presents an approach to identify the state of fine sands on the basis of shear wave velocity measurement. Large body of experimental data was used to derive formulae which relate void ratio with shear wave velocity and mean effective stress for a given material. Two fine sands which contained 8 and 14% of fines were tested. The soils were tested in triaxial tests. Sands specimens were reconstituted in triaxial cell. In order to obtain predetermined void ratio values covering possible widest range of the parameter representing a very loose and dense state as well, the moist tamping method with use of undercompaction technique was adopted. Fully saturated soil underwent staged consolidation at the end of which shear wave velocity was measured. Since volume control of a specimen was enhanced by use of proximity transducers, representative 3 elements sets (i.e. void ratio e, mean effective stress p’ and shear wave velocity VS) describing state of material were obtained. Analysis of the test results revealed that relationship between shear wave velocity and mean effective stress p' can be approximated by power function in distinguished void ratio ranges. This made possible to derive formula for calculating void ratio for a given state of stress on the basis of shear wave velocity measurement. The conclusion concerning sensitivity of this approach to the fines content was presented.

The paper presents the phenomenon of principal stress rotation in cohesive subsoil resulting from its loading or unloading and the impact of this phenomenon on the values of soil shear strength parameters: undrained shear strength τfu, effective cohesion c’, effective angle of internal friction φ’. For this purpose, tests in a triaxial apparatus and torsional shear hollow cylinder apparatus on selected undisturbed cohesive soils: sasiCl, saclSi, clSi, Cl, characterized by different index properties were carried out. Soil shear strength parameters were determined at angle of principal stress rotation α equal to 0° and 90° in tests in triaxial apparatus and α equal to 0°, 15°, 30°, 45°, 60°, 75°, 90° in tests in torsional shear hollow cylinder apparatus. The results of laboratory tests allow to assess the influence of the principal stress rotation on the shear strength parameters that should be used to determine the bearing capacity of the subsoil.