ABSTRACT
High-altitude regions, such as Sela Pass (4175 meters above sea level) in Tawang, Arunachal Pradesh, are subjected to frequent freeze-thaw cycles that significantly compromise subgrade soil strength and bearing capacity, resulting in pavement deformations, increased maintenance costs, and traffic disruptions. This study examines the impact of freeze-thaw (F-T) cycles on the mechanical properties of seasonally frozen soils from Sela Pass through a series of unconfined compressive strength (UCS) tests on specimens subjected to varying F-T cycles. The results revealed that the significant strength loss occurs within the first 3-4 freeze-thaw cycles, with a decrease of approximately 17-20% and after 7 freeze-thaw cycles the UCS decreases by around 32.6%, highlighting the importance of considering freeze-thaw effects in geotechnical de-sign and construction in high altitude regions.
