Study on Mechanical Response and Stability Enhancement of Drainage Channel Structures in Seasonal Frozen Soil Regions

In seasonal frozen soil regions, the structural stability of drainage channels is crucial for regional flood control and industrial production. The drainage channel from Yingxiwa to the southern railway section of Daqing City’s Hongqi Canal Cluster has suffered from long-term neglect, leading to silt accumulation and reed root spread that not only reduced water flow cross-section but more critically significantly weakened the overall structural stability of the channel. During flood seasons, heavy rainfall combined with sedimentation effects causes frequent dike overflow in upstream sections, exacerbating structural damage and severely threatening flood control functions as well as the safety of adjacent oil fields. This study focuses on the strength weakening patterns of channel soil under freeze-thaw cycles and the mechanical failure mechanisms caused by hydraulic forces. Through comprehensive field investigations and hydro-mechanical coupled numerical analysis, we thoroughly deciphered the structural instability mechanisms driven by freeze-thaw-hydrodynamic interactions. Based on this research, we proposed optimization designs aimed at enhancing channel structural stability, including section reshaping based on mechanical analysis and reinforcement measures for critical sections. Hydrogeological conditions were incorporated as essential background constraints, while dredging techniques were considered prerequisites for restoring water flow cross-sections. The findings not only provide a solid theoretical foundation and effective engineering solutions for structural safety design, maintenance, and stability improvement of drainage channels in seasonal frozen soil regions but also demonstrate deep interdisciplinary integration of geotechnical engineering, hydraulics, permafrost science, and structural mechanics. With significant practical value, these results offer substantial benefits for ensuring regional flood control safety and oil field production.