Comparative Study of Anti-Slide Pile Reinforcement Schemes for Expansive Soil Canal Slopes in Cold and Arid Regions

Sliding damage of canal slopes due to the degradation of shear and compression properties of expansive soils caused by long-term dry-wet-freeze-thaw cycles is frequently encountered in canal projects in cold and arid regions. To address this issue, this paper developed a new reinforcing technique for expansive soil canal slopes with monolithic structural anti-slide piles. The sliding damage mechanism of the canal and the reinforcement schemes were analyzed based on the numerical simulations with the FLAC 3D software. The results showed that force redistribution of double-row piles occurred under the longitudinal connection. The maximum reduction in pile displacement was 20.66% under the X-type connection, and the distribution of internal force of pile body changed. The pile forces were redistributed again under the full connection mode, and the pile displacement increased by 4.38%, 95.14%, and 82.09% under the transverse and longitudinal connection mode, the front and rear full connection mode, and the frame full connection mode, respectively. The stability of the canal slope returned to a steady state (F-S > 1.30) in the full connection mode. The findings in this paper can provide guidance for practical engineering.