Abstract: The development of a prediction method for the lateral pressure exerted on expansive soil retaining walls with geosynthetic inclusions has been identified as vital for the design of such structures when saturation of the backfilled expansive soil is achieved. It is assumed that the deformations of expansive soil are composed of swelling deformation due to water absorption by the soil and compression deformation induced by external loads. Within the tenets of elasticity, equations were devised to estimate the elastic modulus and swelling force of expansive soil, respectively. Parameters for these equations were determined through the swelling tests on the expansive soil with loadings. Based on the interaction relationship between the geosynthetic inclusions and the backfilled expansive soil, a practical prediction method for the lateral pressure exerted on expansive soil retaining walls with geosynthetic inclusions was developed when the expansive soil reached saturation, and its performance was fully validated by model tests of the expansive soil retaining wall with soilbag and expanded polystyrene geofoam (EPS) inclusions, respectively. It was observed that the lateral pressures calculated using the proposed method exhibited a well agreement with experimental measurements.

Key words: geosynthetics, expansive soil, retaining wall, lateral pressure, practical prediction method