A three-dimensional study of vegetation management on cut slopes

Abstract

Infrastructure slopes often become covered in dense vegetation due to poor vegetation management. Despite increasing cohesion and enhancing slope stability, trees lead to serviceability problems, primarily towards the end of the summer. Drastic approaches, however, such as vegetation clearance, have caused instabilities during wet seasons. Therefore, appropriate, effective, and continuous vegetation management is of essence and should consider both biodiversity and the engineering asset, while accounting for the contribution of vegetation in battling climate change. Developing numerical methodologies and models can be particularly useful in acquiring insight into the complex mechanism and processes taking place during slope-plant-atmosphere interactions. The work presented here focused on the development of a 3D numerical model to investigate different vegetation management strategies for a slope covered in trees and suffering serviceability problems. Different 3D patterns of tree removal and of replacement of trees with shrubs were considered and the effect of each of these on the serviceability and stability of the slope during the subsequent year was examined. The results demonstrated that replacement was preferable to removal, as stability and serviceability should be considered concurrently, and that, occasionally, clearance may have detrimental effects non only on stability but also on serviceability.