In this thesis, we investigated the influence of the test preparation method of the test specimens on the result of the embeddability tests. The tests were carried out in the laboratory, using the Proctor test, on three clay samples (Pl/Q clay (CL), reference clay (CH) and karst clay (CH)) and on a sample of pyritic charcoal.
The test specimens were prepared by moist preparation method (natural moisture; w0 - moisten or air dry uniformly to the desired moisture) and dry preparation method (pre-drying the material at T = 105 °C and moistening). The moist preparation method of the test specimens corresponds better to the technological processes used for embedding materials in embankments and backfills, but is more demanding and time-consuming compared to the dry preparation method.
The results of the embeddability tests show that different test specimen preparation methods have different effects on different types of materials, even if they are classified in the same way according to the USCS classification. Pl/Q clay (CL) and karst clay (CH) prepared by the moist method show a higher optimum moisture content and a lower maximum dry density than the same clays prepared by the dry method, while the preparation method of the test specimens has no significant effect on the embeddability parameters of the reference clay (CH). In the case of non-plastic pyritic charcoal, which have a character of molasses to silty sand, the preparation method of the test specimens only affects the maximum dry density, which is lower in the case of the dry preparation method.
The influence of the preparation method is also reflected in the unconfined compressive strength of the compacted test specimens and in liquidity limit. Moist-prepared test specimens generally exhibit slightly higher compressive strengths than dry-prepared test specimens. The drying method also lowers the liquidity limit of the clays tested.
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