Study on performance of geocell-reinforced red clay subgrade

Abstract

Three comparative treatment plans are used in red clay subgrade, in order to research the effect of red clay subgrade reinforced with geocell. Multiple subgrade test methods including Benkelman beam, portable falling weight deflectometer, dynamic cone penetrometer and standard vehicle load tests are adopted in the field tests. Test results show that the application of geocell in red clay subgrade can enhance the overall stiffness and strength of the subgrade. The mechanism of geocell in the subgrade is studied. Geocell can provid added confinement on the surbgrade soil.Compared with the red clay subgrade without geocell-reinforcement, the rebound modulus of the red clay subgrade reinforced with 0.1-m-height geocell and 0.05-m-height geocell show a 65% and 33% increase, the dynamic modulus increase by 69% and 38% and the penetrations decrease by 51.7% and 40.4%, respectively. A hard shell layer is formed in the subgrade, after the surbgrade is reinforced with the geocell. Geocell reinforced layer plays mainly the role of stress diffusion. It not only can reduce the additional stress in the subgrade, but also can diminish the influence depth of the vehicle load.