Investigation of the effects of geotextile, waste cherry marble powder and their combinations on the strength properties of clay soils in seasonal freezing areas

Due to the geographical location of our country, four seasons are experienced and therefore the seasonal temperature differences are seen and the stabilization of these soils, which are exposed to freezing-thawing cycles due to the presence of clay soils at many points of the land structure of our country, should be investigated. This thesis aims to investigate the effect of geotextile, waste cherry marble powder and their combinations on the strength characteristics of clay soils in regions where there is a seasonal temperature difference by conducting an experimental study of geotextile, waste cherry marble powder (VMT) and their combinations. For this purpose, the physical properties of the clay used in the experiments and the chemical properties of the cherry marble powder were determined. The samples were prepared by adding different weight ratios (0, 4%, 8%, and 12%) of cherry marble powder, various geotextile layers (single and triple layers), and their combinations to the clay. To examine the strength properties of the stabilized clay samples prepared at the maximum dry unit volume weight ratio under different numbers of freeze-thaw cycles (0, 3, 5, and 7) under various confining pressures (100 kPa, 200 kPa, 300 kPa) undrained-unconsolidated (UU) triaxial tests were carried out. Finally, the stabilized clay samples taken as a result of the experiments were coated and their microstructural properties were examined with the ZEISS EVO MA10 scanning electron microscope. Experimental studies have shown that the increase in freeze-thaw cycles reduces the failure strength of clayey soil. In addition, better effects were observed for the strength reduction caused by freeze-thaw cycles in soil test groups stabilized with different VMT ratios, different geotextile layers, and their combinations. The average UU strengths of soil groups stabilized with only 12% VMT are between 91.09% and 103.38%, and between 219.83% and 270.42% in groups modified with three geotextiles under the maximum number of freeze-thaw cycles. In addition, an increase was observed in the UU strengths between 133.19% and 145.74% in single-layer geotextile and 12% VMT stabilized test groups, and the increase was determined between 258.28%-269.70% for three-layer geotextile and 12% VMT added test groups. On the other hand, as the additive ratios increased, the cohesion of the clayey soil increased significantly and the internal friction angle values of the samples were not sensitive to the additive material, ratio and freeze-thaw cycles. The stability of clayey soils under freeze-thaw cycles in infrastructure construction applications can be significantly improved by the combined use of waste VMTs and different layers of geotextiles.