| Abstract [eng] |
The purpose of the Master's thesis - Investigate the suitability of plastic clay and fine-grained soils for the production of self-compacting modified soils and identify the essential characteristics of the produced product. Tasks of Master's final project: 1. Produce a self-compacting soil that is non-layered, non-segregating and does not exhibit water separation characteristics; 2. Investigate the change of self-compacting soil properties at different sand / clay ratios in soil; 3. Perform microstructural analysis of self-compacting soils with different sand / clay ratios in soil; 4. Determine the re-excavation ability of self-compacting soils. During the research 6 different compositions of self-compacting soil were prepared. Diffusion and viscosity classes were determined of the self-compacting soil mixtures. Hardened specimens were subjected to compression strength, modulus of elasticity, and re-excavation tests, after 7, 14, 28, 56, 112 days of curing. The observed dispersions of the mixtures corresponded to classes SF1 and SF2, viscosity - to class VS1. The moisture content of the samples was 14.5% - 68.2%, densities 1580.53 - 1954.92 kg/m3. The obtained compressive strengths of the specimens were 0.16 - 1.15 MPa, elastic modulus 51.36 - 307.5 MPa. The produced self-compacting soil specimens were difficult, moderate and easy to re-excavate. It has been investigated that as the sand / clay ratio increases, the compression strength, modulus of elasticity, density increases and the ability of re-excavation getting worse. After proceeding microscopic analysis it was observed that with increasing sand / clay ratio in the soil the mixtures are getting more homogeneous. Have been found that sand particles act as an abrasive when mixed with clay and decompose the clay flocculant, so it is recommended to mix atleast 40% sand in self-compacting soil mixture. Master's Final Degree Project consist of 17pcs. of tables, 37pcs. of images, 15 references. |
