Study on the dynamic response of soilbags-reinforced highway subgrade under cyclic loading and influence factors

Abstract

Although soilbag reinforcement is an established environmentally friendly method for highway subgrade enhancement, its working behavior and the factors influencing its performance remain inadequately understood. Model tests were conducted on soilbag-reinforced highway subgrade subjected to cyclic vertical loads are conducted, considering various reinforcement layers, embedded depths, and cyclic load frequencies and amplitudes. It was found that the reinforcement, stress dispersion, and energy dissipation characteristics of the soilbags effectively reduce surface settlement, resilient deformation, and vibrations induced by cyclic loads. Increases in the amplitude and frequency of cyclic loads were observed to lead to greater surface settlement, resilient deformation, and acceleration responses in the soilbag-reinforced subgrades, with more significant reinforcement effects noted under higher load amplitudes and frequencies. It was also demonstrated that a decrease in the embedded depth of the soilbags and an increase in the number of reinforcement layers enhance the subgrades' ability to resist deformation and vibration. A reinforcement cushion composed of multiple layers of soilbags can significantly enhance the overall anti-deformation capacity and vibration reduction and isolation effect of the subgrade. Consequently, this reduces subgrade and pavement deterioration under heavy traffic loads.

Keywords

soilbag / reinforced highway subgrade / cyclic loads / dynamic response / influence factors