Quantitative Analysis of Concrete Lining Damage in Field Canals by Frost Heave Using a Water–Heat–Mechanical Coupling Model

Abstract

Concrete linings of field canals are seriously damaged by frost heave in the north of China. However, the mechanism causing lining damage is too complex to be described quantitatively, and present models are insufficient in considering soil–lining interaction. Based on mechanical analysis and the direct shear test, the restrictive relationship between the freezing soil and lining is introduced as a key point to quantitatively simulate the process of lining damage. Heat convection, solar radiation, and a moving water table boundary are also incorporated in the present model to simulate boundary conditions with daily climate data. Finally, two cases in the Hetao irrigation district are simulated. The developed model agrees with experiment data and can reflect the failure characteristics of lining. The results show: (1) the contact interface between lining and freezing soil will slide early in the freezing season, (2) reducing the freezing strength or weakening the restrictive relationship between the lining and freezing soil can reduce the maximum stress of the lining, (3) new lining structures with shapes like parabola and catenary perform better than a round-bottom-triangular (RT) shape because of a gentler side slope, and (4) large amounts of migration water accumulate and freeze beneath north (shady) slopes and cause a high damage risk for the lining. This paper can provide a reference for the further study of efficient and economical engineering methods for solving the lining damage problem.