EXPERIMENTAL ON CREEP PROPERTIES OF EPS BEADS LIGHT WEIGHT SOIL UNDER DIFFERENT WATER CONTENTS

In order to gain the creep laws of light weight soil which is in the central part of the subgrade under long-term loading, the creep properties of light weight soil and remolded soil with different water contents and axial compression force were analyzed by one-dimensional compression tests. The results show that when other factors are the same, the higher the axial compression force and water content are,the greater the creep deformation of soil samples is.The deformation of light weight soil under loading for one day can basically reach 93%~98% of the whole deformation, and the attenuating creep is obvious. Light weight soil is a kind of structural soil, and it has different creep mechanism with remolded soil. When the axial compression force is no more than the compressed yield stress, the creep deformation is mainly from holes closure, drainage water, solid particles' movement. When the axial compression force is more than the compressed yield stress, the original structure of the light weight soil will be destroyed and EPS beads will be compressed. Based on the attenuation creep characteristics of light weight soil, an empirical creep model is established base on the hyperbolic model. When the axial compression force is less than the compressed yield stress, it can basically reflect the creep laws of light weight soil which is in the central part of the subgrade. By the experiments and theoretical calculation analysis, it is found that the consolidation characteristic of light weight soil is better than that of remolded soil. So the subgrade settlement can reach a stable value after the construction, and the post-construction settlement can almost be neglected during the operation.