نوع مقاله : مقاله پژوهشی
نویسنده
دانشکده مهندسی عمران، دانشگاه صنعتی سهند، تبریز، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسنده [English]
The objective of this study is to compare the effectiveness of industrial wastes including cement kiln dust (CKD), fly ash (FA), and ground granulated blast furnace slag (GGBFS) for the stabilization of clay soils. To chemically stabilize the soil, the optimal amounts of cement kiln dust, 10-20%, class C fly ash, 20-25%, and ground granulated blast furnace slag, 20-30% have been suggested. Considering the pH value of the soil with different percentages of additives, the amount of each additive was considered the same and 20% for better comparison. Standard compaction and California bearing ratio tests were conducted on mixtures. To investigate the microstructural effect of additives, the samples were subjected to scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The results showed that CKD and FA decrease the maximum dry density and increase the optimum moisture content. Meanwhile, GGBFS decreased the optimum moisture content of the sample and increased the maximum dry density. The California bearing ratio in soil stabilized with CKD, FA, and GGBFS were 21.7, 13.3, and 15.7 times that of pure soil, respectively. According to the results of the SEM and XRD analysis, the increase in strength in the stabilized soil is caused by pozzolanic reactions and the creation of cementation products, and as a result, the binding of soil particles and stabilizers and the filling of pores. The higher the amount of free lime in the stabilizer, the greater the increase in soil strength. In practical projects, factors such as the delay time (the time between the first contact of the additive and water and the final compaction of the mixture) and the moisture content that affect the strength parameters should be considered. Also, environmental issues, such as the potential of these additives to enter groundwater, are important.
کلیدواژهها [English]
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