Dispersive clay soils represent a specific type of fine‐grained soils, which can not be determined by the visual classification or using standard identification ‐ classification tests such as granulometric (particle size) analysis, plasticity tests and similar. The paper gives an overview of the results of testing dispersivity of fine‐grained soil using other classification tests: the crumb test, the double hydrometer test and the pinhole test. Tests were conducted on samples: sandy clay embankment dams of “Rovni”, loess from different locations (Zemun, Novi Beograd, Titel, Kelebija, Srbobran, Slankamen, Ruma, Mali Iđoš) and kaolinite sandy clay deposits Grabež ‐ Aranđelovac. In order to improve soil properties, special consideration was given to the influence of soil compaction to dispersion properties. However, dispersion tests obtained with the use of the pinhole method at different degrees of compaction showed that the degree of compaction has no significant effect on the soil behavior, i.e. its class of dispersion.

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Effect of initial conditions on strength of unsaturated compacted loess soil The influence of grain size distribution, initial moisture, dry bulk density, and capillary suction on an increase in shear strength of unsaturated compacted silty loess soil is presented in the paper. The unsaturated soil strength is determined via the experimentally determined dependencies between the moisture-capillary suction and the effective shear strength parameters for saturated soil, c', j'. It is demonstrated that the influence of capillary suction, moisture and dry bulk density on the strength of unsaturated compacted soil reduces with an increase of grain size in soil.

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Disposal of waste in municipal solid waste landfills is the only way of waste disposal in Serbia, with daily compaction and covering with soil material. Due to less space for the construction of new landfills, it is necessary to use their maximum capacity. Well-compacted municipal solid waste takes up less volume and enables safer storage, so it is useful to previously determine the compaction parameters in the laboratory: maximum dry unit weight (γdmax) and optimal water content (wopt). In the practice so far, the standard method has been used to obtain these parameters (Proctor compaction test) which is common in soil mechanics. However, although this methodology has been adopted, different treatments of municipal solid waste at the landfill (including pre-treatment) indicate the need to change this classical approach. Therefore, during the research, various innovative solutions are introduced, such as the change of the classic flat Proctor hammer, by adding spikes, whose function, in addition to compaction, is partial destruction and shredding of municipal waste. In this way, the operation of compactors (hedgehogs) in the field is simulated. The paper presents the behaviour of four artificially prepared samples of municipal solid waste of different composition. The samples were tested in the standard Proctor apparatus at the same compaction energy, using different hammers, a standard flat hammer, and an innovative hammer with spikes. After that, the geotechnical effects of compaction depending on the applied approach were analyzed.