Investigation of Freeze-Thaw Properties of High Plasticity Clay Soil Improved with Lime and Sodium Alginate Biopolymer

In this study, the effect of sodium alginate biopolymer and the effectiveness of sodium alginate biopolymer combined with lime in improving a high-plasticity clay soil were investigated. For this purpose, 0%, 0.5%, 1%, and 1.5% biopolymers and 0%, 2%, 4%, and 6% lime were added to the clay soil. At the end of the 7 and 28 day curing period, the strength results were evaluated with unconfined compressive strength tests. In order to examine the effects of environmental factors, the improved soil samples were exposed to freeze-thaw cycles for 5 and 10 cycles. As a result, it was observed that sodium alginate biopolymers had higher unconfined compressive strengths compared to pure samples at the end of the curing periods. As a result of freeze-thaw cycles, it was determined that the biopolymer additive improved the strength results. When using biopolymer with lime, it was determined as a result of strength tests and freeze-thaw cycles that biopolymer increased the effectiveness of lime in soil improvement. As a result, it has been evaluated that sodium alginate, an environmentally friendly biopolymer, may have positive contributions to engineering applications in the improvement of clay soils.