Investigation of strength properties of clayey soils reinforced using industrial waste, fiber and nanomaterials: Experimental approach and comparative analysis

In geotechnical engineering, clay greatly affects the engineering behavior of the soil with which it interacts. Clay soils, which significantly affect the behavior and engineering properties of soils, bring various problems with their use. Therefore, stabilization of such soils is an important subject of geotechnical engineering. In this thesis, the strength properties of the soil stabilized by adding silica fume, fly ash, nano-SiO2, nanoclay, basalt fiber and glass fiber to the clay soil were investigated and a comparative analysis was made. Accordingly, the physical properties of the clay soil were determined. The samples were prepared in three different conditions: at optimum water content, greater than optimum water content (20%) and less than optimum water content (13%) by adding different proportions of silica fume, fly ash (5%, 10% and 20%), nano-SiO2, nanoclay (0.5%, 0.7% and 1%), basalt fiber, glass fiber (1%, 1.5% and 2%) to clay. Uniaxial unconfined compressive strength (UCS) tests were performed on the specimens prepared at different curing times (0, 3, 7 and 14 days). ZEISS EVO MA10 scanning electron microscope was used for microstructural analysis of the soil specimens. The test results showed that the liquid limit and plastic limit values of the clayey soil prepared with silica fume and fly ash additives decreased. As a result of the proctor test, the optimum water content of the soil increased with the addition of silica fume, fly ash, nano-SiO2 and nanoclay to the clay soil. As a result of the UCS test, the strength values of the specimens prepared with additives increased. The results showed that the use of industrial waste, fiber and nanomaterials had an effect on the physical and engineering properties of the soil and significantly improved the soil.