Analysis of consolidation for soft lying-layer soil of roadbed

Based on Merchant rheological model,the analysis method of one-dimensional consolidation for double lying layered of soft soil under the roadbed was put forward,and the formula of the effective stress at different times was obtained.Using MATLAB software,the formula was compiled into the program,and the curves were made by several main factors to affect the consolidation process of the double layered foundation.The results show that the permeability coefficient of the semi-permeable sand cushion has a significant influence on consolidation of the lying layer of soil.With the increase of K0,soil consolidation process is accelerated and consolidation time is shortened.The elastic modulus of Kelvin spring and viscosity coefficient of the lying layer of soil has great impact on effective stress.With the increase of Es2 and E2 of the bottom layer,the effective stress growth rate increases,consolidation speed increases,and the time that reaches a steady state is shortened,and loading rate also increases.