Numerical Modeling of Geosynthetic-Reinforced Earth Structures and Geosynthetic-Soil Interactions

Abstract

Nowadays geosynthetics have been used as a routine reinforcement in earth structures such as mechanically stabilized earth (MSE) walls, column-supported embankments, soil slopes, and paved/unpaved roads. In those applications, reinforcement mechanisms of the geosynthetics are vaguely described as confinement, interlocking, and load shedding respectively but not fully understood. The uncertainties of the mechanisms have been reflected as overconservativeness, inconsistence and empiricism in current design methods of those applications. Various researches have been widely carried on to investigate the mechanisms of reinforcement of the above mentioned applications, especially the geosynthetic-soil interactions and then quantitatively consider them into design methods. Numerical modeling characterized as cost-and time-saving, is preferred in many circumstances. An appropriate modeling strategy is vital to yield reliable results. This paper reviewed and summarized the modeling techniques used to model modular-block MSE walls, reinforced embankments/slopes, and reinforced paved/unpaved roads, which include conventional continuum modeling based on constitutive relationships as well as micro-mechanical modeling based on Newton’s law of motion, i.e., modeling the soil mass as an assembly of soil particles governed by universal physics principles. The review of conventional continuum modeling includes constitutive models for soils, geosynthetics and other components (e.g., modular blocks), interface models for contacts between dissimilar materials, and simulation of construction, while the review of the micro-mechanical modeling is extended to the principle of the micro-mechanical modeling and how the micro-mechanical modeling is implemented to model the geosynthetic-soil interaction by using the most popular micro-mechanical scheme-PFC as an example. The objective of this paper is to provide a state-of-art review of the various numerical modeling techniques and consequently promote the usage of numerical modeling in research and practice of geosynthetic-reinforced earth structures.