Modelling Of Soil Improvement Induced By Tree Root Suction

Vegetation contributes to weak soil stabilisation through reinforcement of the soil, dissipation of excess pore pressures, and increasing the shear strength by induced matric suction. This paper is concerned with the way vegetation influences soil matric suction, shrinkage, and ground settlement. A mathematical model for the rate of root water uptake that considers ground conditions, type of vegetation and climatic parameters, has been developed. Based on this proposed model, the distribution of moisture and the matric suction profile adjacent to the tree are numerically analysed. Field measurements taken from literature are compared with the authors’ numerical model. The predicted results calculated using the soil, plant, and atmospheric parameters implemented in the numerical model, compared favourably with the measured results, justifying the assumptions upon which the model was developed. Furthermore, through the parametric study and sensitivity analysis, the required accuracies of the model parameters are determined. The findings of this study indicate that due to significant reduction in soil moisture content induced by tree roots, the shear strength of the soil will be enhanced.