Nature-Based Solutions for Enhancing Soil Hydro-Mechanical Properties

The main objective of this study is to gain insights into the soil-water-vegetation-biopolymer interaction and how those interactions control soil hydro-mechanical properties. Four different sample types were prepared, including plain soil, rooted soil, biopolymer-amended soil, and biopolymer-amended rooted soil. After the development of a complete root system, several different hydraulic and mechanical tests were conducted to determine the effect of soil type on engineering properties. In particular, the hydraulic behavior of all samples was investigated by determining the saturated permeability, evaporation, and infiltration rates. Vegetated-biopolymer specimens showed lower permeability and infiltration rates compared to other soils. Finally, direct shear tests were performed to evaluate the shear strength characteristics. The results showed that any combination of the soil treatment led to a slight decrease in the cohesion values leading to deteriorated shear strength. These results are beneficial to engineers in better understanding of vegetation and bio-augmentation techniques and their implementations, especially in severe drought environments.