Deformation characteristics of root-reinforced soil under traffic induced cyclic loading

The slopes adjacent to highways and railroads, which are subjected to both static loads and dynamic loads induced by vehicles and trains, undergo mechanical stresses of varying magnitudes. As long-term cyclic loading can weaken the soil strength and generate excessive deformation, it is necessary to investigate the influence of root distribution on the deformation characteristics of soil reinforced by roots under cyclic loading. With a special focus on the soil stress state, dynamic triaxial tests were conducted to investigate the deformation characteristics induced by cyclic loading, accounting for loading frequency, dynamic stress amplitude and root distribution attributes. The results demonstrate that the crossed arrangement outperforms other patterns under dynamic loads. Root crossed arrangement reduces the plastic deformation of the soil by 70% to 80% and the resilient deformation by 30% to 40%. The soil transient deformation resistance is significantly enhanced through root arrangement, while root cross arrangement leads to a remarkable improvement in the soil dynamic modulus and damping ratio by approximately 200%. The confirmation was obtained that the Hardin and Drnevich hyperbolic model exhibited exceptional conformity and could be effectively employed in analyzing root-reinforced soil.