Repairing expansive soil channel slope with soilbags

Shallow slope failure often occurs in expansive soil channel slopes because of the strong swelling–shrinkage behaviour of expansive soils and well-developed fissures. In this paper, a repair method for expansive soil channel slopes using soilbags is proposed. Model tests were carried out to illustrate the effect of this repair method. The test results indicate that the assembly of soilbags arranged on the slope limits the deformation of expansive soils after water absorption and reduces infiltration and evaporation during the drying–wetting cycle process. A method for analysing the sliding stability of the repaired slope was suggested and a case study of the repair of a 65 m test expansive soil channel slope with soilbags in the South-to-North Water Transfer Project in China was presented. The monitoring of vertical and lateral displacements of the testing slope demonstrates the effectiveness of using soilbags to repair expansive soil channel slopes.