季节性冻土区半填半挖梯形渠道衬砌冻胀力学模型OA

The earthwork balance design in semi-fill-semi-cut canals can significantly optimize the project's earth volume.Placing a fill layer to keep the structure away from groundwater effectively reduces frost damage risks;how-ever,there is still a lack of dedicated frost heave analysis models for such structures.This paper presents a frost heave mechanical model for semi-fill-semi-cut trapezoidal lined canals in seasonal frozen regions,based on the dif-ferential frost heave characteristics of the fill layer and the native soil layer,combined with elastic frozen soil founda-tion beam theory and a modified initial parameter method.By introducing boundary conditions at the ends and conti-nuity conditions at the interface of the dual soil layers,analytical expressions for the frost heave displacement and internal forces in the lining slab are derived.The proposed model,along with a single-layer model and the finite ele-ment method,is applied to a practical engineering case for comparative analysis.The results show that the frost heave displacements of the lining slab computed by the proposed model match well with field measurements in both magni-tude and trend,demonstrating the model's applicability and reliability.The frost heave displacement and internal force distribution in the lining slab exhibit a two-segment characteristic,appropriately reflecting the"dual soil layer"structural feature.The maximum bending moment calculated by the proposed model is 24.6％smaller than that from the single-layer model.Areas with smaller free frost heave in the subsoil exhibit a"restraining effect"on the frost deformation of adjacent lining sections.The hazardous zones identified based on stress analysis on the upper surface are consistent with field survey results in the irrigation area.The findings provide valuable references for the anti-frost design of semi-fill-semi-cut canals and other frozen soil engineering structures with similar differential frost heave properties.