Application of UH model to analysis of deformation of double-layer subgrade

Based on the UH model proposed by Yao et al, the initial over-consolidation ratio (OCR) is introduced to the finite element program of UH model. By setting different OCRs for different soil layers, the soft and hard degrees of soils are controlled. The finite element analysis of strong-over-soft double-layer subgrade is performed by using the finite element program of UH model. Firstly, the additional stress calculated by using the UH model, the simplified double-layer subgrade stress coefficient method and the Boussinesq elastic theory are compared. The comparisons indicate that the UH model has superiority in the analysis of the stress characteristics of double-layer subgrade, and it can reflect the stress diffusion phenomenon of strong-over-soft double-layer subgrade. Then the additional stress of strong-over-soft double-layer subgrade with different OCRs is calculated by the finite element program of UH model, and the effect of OCR on the stress state of double-layer subgrade is studied. Finally, the finite element analysis of the consolidation settlement in the strong-over-soft double-layer subgrade is performed. The subgrade settlement, stress-strain behavior and change of pore pressure in double-layer subgrade are studied.