Root-reinforced sand: kinematic response of the soil

Abstract

The influence of the soil on the growth of a root system has been largely investigated. By contrast, the aim of this work is to go deep into the details of how the soil may be influenced by the root system. In particular, the root growth process and its potential to improve the soil strength is explored. Even though roots can be seen as fiber-like reinforcements, their growth changes the soil microstructure. Consequently, one of the objectives is to understand how the water content and the soil displacement fields evolve when an inclusion expands radially and axially. In particular, an investigation was carried on to characterise the deformation of the solid phase of the soil, due to the root growth. A series of in-vivo x-ray tomographies was acquired with Maize seeds growing roots into a coarse Hostun HN1.5-2 sand. Digital Image Correlation is used to calculate the soil 3D displacement fields around the growing plant roots.

When nature meets technology: AI-informed discovery of soil-water-root physical interaction

“…In the applications of geotechnical engineering where soil behaviours altered by plant roots are of major concern, research of this kind of pore-level root-soil interaction is at its infancy stage. Only in recent years has micromechanical root-soil interaction been studied in terms of how root exploration in the soil pore space affects the kinematics of soil grains [31] and how the kinematics of roots evolve as their mechanical properties are mobilised to resist external loading transferred from the soil [61]. Certainly, more research is needed to reveal the underlying mechanisms, especially at pore-scale which (1) underpins many rootsoil physical interaction that cannot be easily identified at element scale or larger; and (2) are fundamentals to unify the root effects on the hydromechanical properties of unsaturated soils, aiding the explanation of some of the contradicting data found in the literature.…”

Recent Advances in Nature-Inspired Solutions for Ground Engineering (NiSE)

“…Complex biological processes that occur within the soil may also be visualised. μCT has been used to study the interaction of root growth with soil, and how root growth affects water uptake [61]. It has been used to study soil response due to ice formation in pores during freeze-thaw cycles [62].…”

Imaging the root–rhizosphere interface using micro computed tomography: quantifying void ratio and root volume ratio profiles

“…Soil structure changes, such as particle organisation and increases in bulk density can strongly affect the growth and diameter of roots [6]. Roots can also cause changes in soil structure [7]. A recent study by Lucas et al [8] suggested that roots compact the soil, if the initial soil fabric does not offer a sufficient pore volume.…”